Commercial Refrigeration Maintenance

Commercial Refrigeration Maintenance
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
PAGE iii
ADDITIONAL ACKNOWLEDGEMENTS
This Standard and all earlier working/review drafts of this Standard are protected by copyright. By
making this document available for use and adoption by public authorities and others, ACCA does not
waive any rights in copyright to this document. No part of this specification or earlier working/review
drafts of this specification may be reproduced, stored in a retrieval system or transmitted in any form by
any technology without permission from ACCA. Address requests to reproduce, store, or transmit to: the
ACCA offices in Arlington, Virginia.
© 2015, Air Conditioning Contractors of America
2800 Shirlington Road, Suite 300
Arlington, VA 22206
www.acca.org
Adoption by Reference
Public authorities and others are encouraged to reference this document in laws, ordinances, regulations,
administrative orders, or similar instruments. Any deletions, additions, and changes desired by the
adopting authority must be noted separately. The term “adoption by reference” means the citing of title
and publishing information only.
Disclaimer and Legal Notice
Diligence has been exercised in the production of this Standard. The content is based on an industry
consensus of recognized good practices. The guidance provided by this publication does not constitute a
warranty, guarantee, or endorsement of any concept, observation, recommendation, procedure, process,
formula, data-set, product, or service. ACCA, members of the Standards Development Committee,
Review Committee, Standards Task Team, and the document reviewers do not warranty or guarantee that
the information contained in this publication is free of errors, omissions, misinterpretations, or that it will
not be modified or invalidated by additional scrutiny, analysis, or investigation. The entire risk associated
with the use of the information provided by this Standard is assumed by the user.
ACCA does not take any position with respect to the validity of any patent or copyrights asserted in
connection with any items, processes, procedures, or apparatus which are mentioned in or are the subject
of this document. ACCA disclaims liability of the infringement of any patent resulting from the use of or
reliance on this document. Users of this document are expressly advised that determination of the validity
of any such patent or copyrights, and the risk of infringement of such rights, is entirely their own
responsibility. Users of this document should consult applicable federal, state, and local laws and
regulations. ACCA does not, by the publication of this document, intend to urge action that is not in
compliance with applicable laws, and this document may not be construed as doing so. Nothing in this
Standard should be construed as providing legal advice, and the content is not a substitute for obtaining
legal counsel from the reader’s own lawyer in the appropriate jurisdiction or state.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
PAGE ii
DISCLAIMER AND LEGAL NOTICE
ACKNOWLEDGEMENTS
ACCA acknowledges the guidance and diligence provided by the diverse expertise embodied in the
membership of the QMref Development Committee (2014):
John Billheimer (MAS Services; Livermore, CA)
Brian Buynacek, P.E. (Emerson Climate Technologies; Orchard Park, NY)
Robert Champe (Shearer Heating A/C & Refrigeration, Inc.; Washington, PA)
Luis Romeo Escobar (ACCA; Arlington, VA)
Greg Gustafson (Zero Zone; North Prairie, WI)
Danny Halel (Hussmann Corp.; Bridgeton, MO)
Phil London (Thermal Concepts, Inc.; Davie, FL)
Larry Meeker (Target Co.; Burnsville, MN)
Marc Newman (Standard Refrigerators, Inc.; Long Island City, NY)
Jerry Rumple (Kroger Co.; Greenwood, IN)
Dick Shaw (ACCA; Grand Rapids, MI)
Dale Sizemore (Heatcraft / Kysor Warren; Columbus, GA)
Steve Wright Sr. (Wright Brothers Inc.; Hampton, GA)
Special acknowledgements and appreciation go to Bob Champe for serving as Chair of the Committee.
ADDITIONAL ACKNOWLEDGEMENTS
This document has received helpful comments and input from numerous knowledgeable individuals.
These included:
Glenn Hourahan (ACCA; Arlington, VA)
Joe Kokinda (Professional HVAC/R Services, Inc; Avon, OH)
Neil Monson (Target; Minneapolis, MN)
Don Prather (ACCA; Arlington, VA)
John Sedine (Engineered Heating & Cooling; Cedar Springs, MI)
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
PAGE v
INTRODUCTION
INTRODUCTION
[This Introduction is not part of the Standard. It is merely informative and does not
contain requirements necessary for conformance to the Standard. It has not been
processed according to the ANSI requirements for a Standard and may contain material
that has not been subject to public review or a consensus process. Unresolved objectors
on informative material are not offered the right to appeal at ACCA or ANSI.]
Commercial refrigeration equipment and systems require routine monitoring, evaluation, adjustments,
cleaning, and eventual replacement of components. Regularly scheduled inspections and maintenance are
often required to maintain the original equipment manufacturer (OEM) warranty.
This Standard prescribes inspection tasks and offers recommended corrective actions to maintain
commonly installed commercial refrigeration equipment and systems found in supermarkets, convenience
stores, refrigerated warehouses, etc. Equipment checklists are provided by equipment type and detail the
minimum visual inspections, performance tests, measurements, and component evaluations.
Recommended corrective actions in the Standard provide generic guidance designed to maintain
refrigeration equipment in good working order. Specific instructions from the equipment manufacturer
are also to be followed. Additionally, the Standard provides guidance when special operating
circumstances may require additional attention.
Conducting regularly scheduled inspections, maintenance, and remediation of commercial refrigeration
equipment prolongs its efficiency, promotes product safety, supports lower utility costs, guards against
unexpected failures, and prolongs equipment life. Everyone benefits when refrigeration systems operate
efficiently within the required temperature ranges.
To maximize the effectiveness of a maintenance program, the equipment must first be designed and
installed according to the manufacturer’s instructions and applicable codes.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
TABLE OF CONTENTS
PAGE vi
TABLE OF CONTENTS
ACKNOWLEDGEMENTS ..................................................................................................................................... IV
INTRODUCTION ...................................................................................................................................................... V
1.0
PURPOSE ......................................................................................................................................................... 7
2.0
SCOPE ............................................................................................................................................................... 7
3.0
PROGRAM EXECUTION .............................................................................................................................. 7
4.0
DOCUMENTATION ....................................................................................................................................... 8
5.0
MAINTENANCE TASKS................................................................................................................................ 9
Checklist 5.1 Beverage Dispensers .................................................................................................. 11
Checklist 5.2 Cascade....................................................................................................................... 12
Checklist 5.3 Service Case ............................................................................................................... 13
Checklist 5.4 Food Prep Tables (Reach-In) ..................................................................................... 15
Checklist 5.5 Frozen Carbonated Beverage Machines ..................................................................... 17
Checklist 5.6 Heat Recovery ............................................................................................................ 19
Checklist 5.7 Ice Makers / Ice Machines.......................................................................................... 20
Checklist 5.8 Industrial Refrigeration Built-Up Systems ................................................................. 22
Checklist 5.9 Parallel Rack Direct Expansion .................................................................................. 24
Checklist 5.10 Reach-In ................................................................................................................... 27
Checklist 5.11 Service Over Counter (Reach-In) ............................................................................. 29
Checklist 5.12 Single Condensing Unit............................................................................................ 31
Checklist 5.13 Soft Serve Machines .................................................................................................. 33
Checklist 5.14 Walk-In..................................................................................................................... 35
APPENDIX A – DEFINITIONS .............................................................................................................................. 39
APPENDIX B – REFRIGERATION BIBLIOGRAPHY & RESOURCES ......................................................... 44
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
PURPOSE / SCOPE / EXECUTION
1.0
Page 7
PURPOSE
This standard establishes a minimum maintenance program for maintaining refrigeration
equipment found in supermarkets, convenience stores, food service, and warehouses, operating
with saturated suction temperatures between -40°F and +40°F.
2.0
SCOPE
2.1 This Standard provides minimum requirements for the assessment and maintenance of
commercial refrigeration equipment typically found in supermarkets, convenience stores,
institutional applications, food services, warehouses, and similar applications operating at
medium- and low-temperature refrigeration conditions (e.g., saturated suction temperatures
between -40°F and 40°F).
2.2 This Standard includes checklist tasks for inspecting, testing, and measuring the mechanical,
electrical, and controls systems of commercial refrigeration systems. The checklists also
provide recommended corrective actions to remedy identified faults (e.g., cleaning,
adjusting, and/or replacing components and equipment).
2.3 This Standard presumes that the refrigeration system was designed, installed, and operated
in accordance with OEM instructions, applicable codes, and other industry requirements.
2.4 This Standard shall not be used to circumvent safety, health, environmental, local/state
ordinances, or the equipment manufacturer’s requirements.
2.5 Systems utilizing ammonia, carbon dioxide (CO2), or flammable refrigerants (such as
hydrocarbons) may require additional or different inspection tasks and/or corrective actions.
This standard defers to the OEM’s instructions and to the industry standards contained in
Appendix B – Bibliography.
2.6 This Standard excludes transport refrigeration.
3.0
PROGRAM EXECUTION
A maintenance program seeks to eliminate deficiencies that degrade or impair the refrigeration
system, including its components. The technician shall recommend actions to correct these
deficiencies. The following are the responsibilities and elements for a maintenance program:
3.1 Facility owner’s responsibilities: The owner is ultimately responsible for the refrigeration
equipment’s required maintenance. Owners shall use appropriately licensed and certified
commercial refrigeration technicians and/or a contractor to perform inspection tasks or to
implement a maintenance program. The owner is responsible for authorizing corrective
actions, as included in the contract, and determining which corrective actions will require
further authorization to be performed.
3.2 Commercial refrigeration contractor’s responsibilities: Appropriately licensed and certified
technicians shall:


Inspect all pertinent refrigeration equipment and components to identify the faults
which violate the following applicable documents: manufacturer’s instructions,
manufacturer’s warranty requirement, building codes, occupant safety or health
standards, environmental regulations, and recognized industry good practices.
Inform the customer of improper operation finding(s), corrective action(s) taken,
corrective action(s) recommended, and the price to undertake the recommended
action(s).
3.3 Maintenance inspection elements:
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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4.0
PURPOSE, SCOPE, EXECUTION
3.3.1
Inventory: Identify and record the refrigeration system(s) inventory of
equipment, controls, components, and accessories.
3.3.2
Equipment maintenance checklists: From Section 5 (Maintenance Tasks),
identify appropriate checklists for each piece of equipment in the inventory.
3.3.3
Code requirements: Identify and observe the applicable code references (e.g.,
International Mechanical Code, Uniform Mechanical Code, National Fire
Protection Association, etc.).
3.3.4
Performance objectives: Identify minimum equipment performance criteria
based on the manufacturer’s performance data, code requirements, and industry
standards.
3.3.5
Industry standards: Follow recognized industry standards and practices; see
Appendix B.
DOCUMENTATION
The commercial refrigeration technician records measurements, observations, and recommends
corrective action(s) to maintain the system’s ability to function properly and efficiently. The
minimum documentation shall identify:
4.1 Inventory: The inventory of the equipment for the facility’s refrigeration system(s) per
Section 3.3.1.
4.2 Checklists: Those applicable tasks for the inspected equipment from Section 5.0 Inspection
Tasks and Recommended Corrective Actions.
4.3 Code violations: Violations of the applicable codes.
4.4 Performance objectives: The refrigeration system’s measured performance compared to the
performance objectives per Section 3.3.4.
4.5 External conditions: Observed circumstances apart from the refrigeration system which
cause health and safety issues, accelerated wear, poor performance, or increased energy use.
4.6 Inaccessible items: Components that are inaccessible, or if the limited accessibility of the
component impairs the inspection or maintenance task.
4.7 Corrective actions: Those tasks, included in the contractual agreement or authorized by the
owner, undertaken to meet the performance objectives, improve system performance, safety,
efficiency, or durability.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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MAINTENANCE TASKS
5.0
MAINTENANCE TASKS
This Section identifies inspection tasks and recommended corrective actions for commercial
refrigeration equipment.

Inspection tasks: This portion of the checklist describes the minimum tasks required for
most major pieces of commercial equipment.

Recommended corrective actions: The checklists offer remedies for faults identified
during the inspection process. The technician shall inform (or follow guidance for
informing) the facility owner of remedies included as part of the inspection and
coordinate prior approval for remedies, which are excluded from the inspection. All
corrective actions shall be performed in accordance with the applicable OEM’s
instructions and applicable building codes.

Inspection scheduling:

1.
The commercial refrigeration technician shall advise of the need to change the
inspection tasks or frequency of inspection to address deficiencies if
unacceptable performance is found during two successive inspections. Changes
are subject to the terms of the contractual agreement.
2.
The commercial refrigeration technician shall advise of the need to change the
inspection tasks or frequency of inspection if acceptable performance is found
during three successive inspections. Changes are subject to the terms of the
contractual agreement.
Component / equipment listings: The major pieces of refrigeration equipment and
accessories shall have checklists. If a system in the commercial facility is not covered by
a checklist, a checklist from functions similar to those listed on checklists 5.1 – 5.14 shall
be assembled.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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MAINTENANCE TASKS
Component /
Equipment
Component / Equipment Description
Beverage Dispensers
Cascade
Service Case
Food Prep Tables
(Reach-In)
Frozen Carbonated
Beverage Machine
Heat Recovery
Ice Makers and Ice
Machines
Industrial Refrigeration
Built-Up Systems
(100 ton and above)
Parallel Rack
Reach-In
Service Over Counter
(Reach-In)
Single Condensing Unit
Soft-Serve Machines
Walk-In
A refrigeration system designed to mix and chill beverages to
the serving temperature.
A system containing two or more refrigeration cycles, which
may use different refrigerants, and linked through a heat
exchanger. Often used to provide lower temperatures more
economically.
A refrigerated unit designed without customer access, having
reach-in access from the service side only.
Food working and service refrigeration units that come in many
styles and configurations often designed to hold products in
reach-in doors or drawers. Two main types are available: (1)
food prep tables have food containers that are accessed from
the top at the specified temperature, and (2) cold-top tables
generally have a marble top and are designed for working on
cold service food prep.
A refrigerated dispenser designed to stir and chill carbonated
beverages and provide a frozen product in the form of a semifrozen slush.
A method of utilizing refrigeration system waste heat to
increase energy efficiency elsewhere.
A refrigerated unit that freezes water to make ice in many
configurations, e.g., flakes, cubes, chips.
A system engineered for an industrial setting where variable
loads are taken into consideration.
Checklist
Number
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
A configuration for compressors, piped in parallel, and a
condenser or condensers located remotely, away from the
refrigeration evaporators and cooling units.
A commercial refrigeration unit, horizontal or vertical,
generally designed to operate between -40°F and +40°F, where
the consumer has access by opening a door. These units are
either remote or self-contained.
Refrigerated units designed to display products below a solid
countertop. These units may or may not have an accessible
reach-in refrigerated or non-refrigerated storage built-in below.
5.10
A package unit designed for use with one or more evaporators.
5.12
A refrigerated dispenser designer to stir and chill liquid mixes
and provide frozen custard, ice cream, and yogurt.
Refrigerated cooling or freezing units with walk-in access.
Often a walk-in freezer is located within a walk-in cooler.
Table 1: Component and Equipment Descriptions
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
5.9
5.11
5.13
5.14
MAINTENANCE TASKS
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Checklist 5.1 Beverage Dispensers
Inspection Task
Rec. Corrective Actions
Frequency
1. Check for general cleanliness.
Clean drain pan, grid, splash panel,
nozzles and diffusers as required or
permitted.
Clean, repair or replace as
necessary.
Monthly
Adjust as required. Repair or
replace as needed.
Repair/replace carbonator pump,
motor, electrode, or liquid level
control as needed.
Repair/replace as needed.
Adjust CO2 pressure, or replace
tank as needed.
Monthly
2. Check refrigeration system for
proper operation (see condensing
units from reach-ins systems for
specifics).
3. Check water regulating valve.
4. Check carbonator for proper
operation.
5. Check high pressure regulator.
6. Check CO2 supply.
Monthly
Monthly
Monthly
Monthly
Independent Notes:
 All cleaning must meet local health department regulations.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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MAINTENANCE TASKS
Checklist 5.2 Cascade
Inspection Task
Rec. Corrective Actions
Frequency
NOTE: By definition, cascade systems are two or more refrigeration systems. Hence, the appropriate
number of checklists are to be selected (or assembled) and those actions undertaken.
1. Check condenser fan, as appropriate. Vacuum or clean as necessary.
Bi-annual
2. Check condenser filter, as
Clean or replace as necessary.
Bi-annual
appropriate.
3. Check gasket for punctures or tears
Clean or replace as necessary.
Bi-annual
4. (Controls) Check control strategy for Reprogram as required.
Annually
consistency with customer
expectations.
5. (Controls) Check function of
Calibrate or replace.
Annually
transducers and temperature sensors
for accuracy.
6. (Heat exchanger) Check for ice
Reinsulate if frost or ice is found.
Annually
buildup on the heat exchanger.
Independent Notes:
 As appropriate, find other checklist for the system being worked on.
 These systems are ultra-low temperature freezers, generally seen in laboratories.
 Typical maintenance is for electrical components; generally, once the technician has to go into the system
then it will be replaced.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
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Checklist 5.3 Service Case
Inspection Task
Exterior Surroundings
1. Check automatic door closure for
proper operation.
2. Check that no water is coming from
the display case (e.g., condensation)
or water is present around display
case (e.g., drainage issue).
3. Check that all trim is properly
attached and that electrical covers are
secure.
4. Check that the case is being properly
loaded.
5. Check the display case ambient fans
for proper operation (e.g., motor end
plate noise).
6. Check for ice build-up and air
leakage in seams of display case.
7. Check that store conditions do not
exceed 75°F DB 55%RH.
8. Check that there is no air infiltrating
into case.
9. Check that the case is properly
plumbed and level.
Refrigerated Area
10. Check for ice build-up at TXV area,
U-bends, or in seams of display case.
11. Check for refrigerant leaks.
12. Check that the drain area is clear.
13. Check discharge air grille
(honeycomb) for cleanliness.
14. Check display case lighting for
proper operation.
15. Check display case wiring
connections and that the wire is
properly stowed.
16. Check for OEM minimum rated feet
per minute (fpm) airflow at the air
discharge.
17. Check anti-sweat heater for proper
operation.
18. Check fan operation and drain
heaters.
19. Check defrost and defrost
Rec. Corrective Actions
Frequency
Repair or replace as necessary.
Quarterly
Take required steps to ensure that
condensate pan and drain line are
not obstructed. Ensure that the antisweat heater is functioning
properly.
Repair as needed.
Quarterly
Inform the owner/location manager
of improper loading.
Repair or replace as needed.
Quarterly
Remove build-up, and use food
grade sealant for leaks.
Make sure that environmental
system at the location is functioning
properly.
Take required steps to remove the
cause of infiltration (e.g., an errant
air duct).
Inform the owner when the service
case is not level and/or condensate
drainage is not sloped properly.
Quarterly
Remove build-up, and use food
grade sealant for leaks.
Consult with the manager and
schedule repair as needed.
Clean the interior per the
manufacturer’s instructions and
flush the drain.
Clean as necessary.
Quarterly
Advise the manager if not operating
properly.
Secure as needed.
Quarterly
Inform owner/location manager
when airflow is lower than OEM
minimum requirements.
Repair or replace as needed.
Quarterly
Repair or replace as needed.
Annually
Adjust, program, repair, or replace
Annually
Quarterly
Quarterly
Annually
Annually
Annually
Quarterly
Quarterly
Quarterly
Quarterly
Annually
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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MAINTENANCE TASKS
termination for proper operation.
20. Check temperature control settings.
21. Check EPR settings.
22. Check TXV has proper superheat.
If Self-Contained
23. Check the condenser and compressor
compartment area for debris, proper
fan operation.
24. Check re-evaporator pan.
25. Check electrical wiring in
compressor compartment area.
as needed.
Adjust to design or manufacturer’s
specifications as needed.
Adjust to design or manufacturer’s
specifications as needed.
Ascertain the cause of improper
superheat, and take relevant
corrective actions based on the
cause.
Annually
Annually
Annually
Remove debris, check airflow,
Quarterly
clean condenser coil, and replace
fan motor as needed.
Clean or repair as needed.
Quarterly
Repair, replace, and stow as needed. Quarterly
Independent Notes:
 Before taking any corrective action that would require turning off the case, consult with the manager so that
the proper steps are taken with respect to contents of the case and scheduling.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 15
Checklist 5.4 Food Prep Tables (Reach-In)
Inspection Task1
Rec. Corrective Actions
Frequency
Clean as necessary per
manufacturer’s specifications.
Clean or replace as necessary.
Remove light build-up with a brush
or a vacuum with a brush
attachment.
Remove moderate buildup with
compressed air, followed by
brushing as necessary.
Remove heavy buildup per
manufacturer’s specifications.
Clean as necessary.
If washing the fan blades is
necessary, cover the fan motor to
prevent moisture damage.
Clean the louvers on the
downstream side of the condenser
and/or gravity dampers if
applicable.
Ensure sure that the fan shroud is
present and intact.
Straighten with fin comb as
necessary.
Monthly
Ensure it is level and trapping.
Connect drain tube to evaporator
drain pain as necessary.
Remove drain tube obstructions as
necessary.
Replace heater if amperage does not
meet manufacturer’s specifications.
Clean with a brush or soapy water
as necessary.
Straighten fins or replace
evaporator coil if necessary.
Remove any obstructions that block
air to the evaporator.
Quarterly
Quarterly
Adjust the knob until the time
matches the manufacturer’s
specification.
Adjust until it matches the
manufacturer’s specified set point.
Quarterly
Replace broken guides as
necessary.
Clean with mild soap and water
solution as necessary. Follow with
fresh water rinse.
Quarterly
2
Condenser
1. Check condenser coil surface for
dust, dirt, and lint.
2. Check condenser intake air filter.
3. Shine a light on the condenser
surface to check for dirt inside the
condenser.
4. Check fan blades and motor for
cleanliness.
5. Check condenser for adequate
airflow and no recirculation of
discharge air.
6. Check condition of fins as
applicable.
Evaporator Coil
7. Check drain tap.
8. Check drain tube.
9. Check self-contained water removal
system (condensate drain pan).
10. Check for dirt, build-up, and foreign
objects.
11. Check the integrity of fins.
12. Check for obstructions to proper
airflow.
Controls
13. Check operation defrost control set
time.
14. Check case temperature set point.
Doors/Gaskets
15. Check door slides or guides.
16. Check door gaskets for cleanliness
and presence of mold or mildew.
Monthly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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MAINTENANCE TASKS
17. Check door gaskets for proper
sealing.
18. Check door hinges for looseness.
19. Check amperage of anti-sweat,
frame, and door heaters.
Walls/Panel Interior
20. Check refrigeration tubing is not
rubbing or vibrating against other
tubing or panel.
21. Check cabinet exterior and interior
for cleanliness.
22. Check casters for corrosion.
23. Check insulation and areas of
moisture accumulation for biological
growth.
24. Check condition of shelves.
Surroundings
25. Check for anything stacked on or
around the machine.
26. Check area surrounding the machine
for cleanliness.
Additional
27. Check the pan chillers temperature
and defrost.
28. Check box fans to condiment pans
for obstructions to proper airflow.
29. Check doors/drawers for proper fit.
30. Check refrigerant line insulation.
Adjust or replace as necessary.
Quarterly
Tighten the screws that mount the
hinge brackets to the unit frame as
necessary.
Replace broken hinges as
necessary.
Replace if amperage does not meet
manufacturer’s specifications.
Quarterly
Correct as necessary.
Quarterly
Clean with mild soap and water
solution as necessary. Follow with
fresh water rinse.
Wipe with damp cloth as necessary.
Lubricate per manufacturer’s
specifications.
Clean or disinfect as necessary.
Quarterly
Clean as necessary.
Quarterly
Advise customer to remove as
necessary.
Advise customer to clean as
necessary.
Quarterly
Adjust to match manufacturer’s
specifications.
Remove any obstructions that block
air to evaporator.
Adjust as necessary or replace
rollers as necessary.
Repair or replace as necessary.
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Notes:
1.
2.
During the course of the regular maintenance inspection, the technician should notify the owner if they see
an installation issue that could compromise food safety or equipment performance. These issues may
include: equipment placed in direct sunlight, ambient air temperatures exceeding OEM thresholds, heat
from other appliances affecting the condenser, impingement of minimum air inlet clearance for the
condenser because equipment is placed too close to the wall.
Disconnect electric power before cleaning.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 17
Checklist 5.5 Frozen Carbonated Beverage Machines1,2
Inspection Task
Exterior
1. Check that the refrigeration tubing is
not rubbing or vibrating against other
tubing or panels.
2. Check refrigeration tubing insulation.
3. Check that nothing is stacked on or
around the machine which impedes
appropriate airflow through and
around machine per OEM
specifications.
4. Check for dust and dirt on the
outside of the machine.
Rec. Corrective Actions
Frequency
Adjust as necessary.
Semi-annual
Replace or repair as necessary.
Clear away as necessary.
Semi-annual
Semi-annual
(daily)
Sponge off with mild soap and
water, then dry with a soft, clean
cloth. NSF-approved commercial
stainless steel cleaner may be used
if applicable.
5. Check the integrity of all panels and
Replace fasteners as needed to
supports on equipment, as applicable. ensure proper integrity and
fit/finish.
Interior - Mechanical
6. Check condenser for adequate
Clear away or move the machine as
airflow, and intake and ambient air
necessary.
temperature3 for recirculation of
discharge air, per OEM
specifications.
7. Check the air filter for dust, grease,
Clean air filter as necessary.
and grime.
8. Disconnect electric power and check Clean in accordance with OEM
the outside of condenser and fins for specifications (e.g., with soft brush,
dirt.
coil cleaner, or vacuum with brush
attachment. Brush from top to
bottom, not side to side. Be careful
in order to not bend fins).
9. Check the condenser fan motor for
Lubricate, repair (e.g., tighten,
worn bearings and secure mounting.
weld, etc.), or replace as necessary.
10. Check fan blades and fan housing for Clean, repair, or replace as
dirt, bending, missing shroud.
necessary.
11. With electric power on, check
Repair or replace as necessary.
condenser fan motor for proper
operation and integrity of bearings
(heat, vibration, noise).
12. Check air-cooled condenser surfaces Straighten, repair, clean, or replace
for damage (e.g., bent fins) or
as necessary.
evidence of leaks.
Cleaning and Sanitizing
13. Review operator’s sanitation
Notify them that sanitation must
policies.
comply with federal, state, and local
regulations and codes. Machine
must be sanitized after service.
Storage (Winter or Extended)
14. Check the condition of the
Ensure that the equipment has been
equipment prior to storage.
cleaned and shut down for extended
Semi-annual
(daily)
Semi-annual
Monthly
Monthly
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Quarterly
Annual
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 18
MAINTENANCE TASKS
storage in accordance with OEM
specifications. Water must be
removed from water-cooled
condensers prior to storage.
Note:
1.
2.
3.
Ambient conditions of machine operation must comply with applicable codes, regulations, and OEM
specifications.
The International Energy Conservation Code stipulates minimum insulation wall thickness for this type of
equipment in order to prevent water and mold accumulation. The technician should notify the owner if
newly-installed equipment does not comply with the requirements of the locally enforced code.
These two temperatures should be equal or near equal.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 19
Checklist 5.6 Heat Recovery
Inspection Task
Rec. Corrective Actions
Frequency
1. Check for scaling, erosion, corrosion,
algae or slime in heat recovery loop.
2. Check the water tube for scaling.
Treat the water as required.
Semi-annual
Clean water tube using mild scale
removing compound following the
de-scaler manufacturer’s
instructions.
Install heat tape or add freeze
inhibit fluid to the partial heat
recovery water loop as needed.
Replace as needed.
Semi-annual
Replace heat exchanger when
pressure drop is 10 psi greater than
baseline.
Repair or replace as necessary.
Semi-annual
Repair or replace as necessary.
Annually
Repair or replace as necessary.
Annually
Repair or replace as necessary.
Per OEM instructions
Repair as necessary.
Quarterly
3. Check inlet and outlet piping for
freeze protection measures.
4. Inspect anodes.
Flat Plate Heat Exchangers
5. Check the pressure drop across the
heat exchanger on the refrigerant
side.
6. Check the function of the check
valve in the heat reclaim return line
to ensure no backflow through the
heat reclaim coil when heat reclaim
is not required.
7. Check the operation of the
temperature sensor driving the heat
reclaim valve (three way or
motorized ball valve).
8. Check the operation of the heat
reclaim valve (three way or
motorized ball valve).
9. Check the water/glycol pumps on the
secondary side for operation and
proper flow.
10. Check to see that the bypass switch
is not initiated.
Semi-annual
Every three years
Annually
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 20
MAINTENANCE TASKS
Checklist 5.7 Ice Makers / Ice Machines
Inspection Task
Exterior
1. Check all water fittings and water
supply lines and drains for leaks.
2. Check that the refrigeration tubing is
not rubbing or vibrating against other
tubing or panels.
3. Check refrigeration tubing insulation.
4. Check that nothing is stacked on or
around the ice machine which
impedes appropriate airflow through
and around ice machine per OEM
specifications.
5. Check for dust and dirt on the
outside of the ice machine.
Rec. Corrective Actions
Frequency
Replace and repair as necessary.
Semi-annual
Adjust as necessary.
Semi-annual
Replace or repair as necessary.
Clear away as necessary.
Semi-annual
Semi-annual
Sponge off with mild soap and
water, then dry with a soft, clean
cloth. Commercial stainless steel
cleaner may be used if applicable.
6. Check the integrity of all panels and
Replace fasteners as needed to
supports on equipment, as applicable. ensure proper integrity, and
fit/finish.
7. Check water filters.
Replace per OEM specifications.
Interior - Mechanical
8. Check condenser for adequate
airflow and inadequate circulation of
discharge air, per OEM
specifications.
9. Disconnect electric power and check
the outside of condenser and fins for
dirt.
10. Check the condenser fan motor for
worn bearings and secure mounting.
11. Check fins for bending.
12. Check evaporator and water
distribution system for scale buildup.
13. Check water reservoir(s) for solids or
mineral buildup.
14. Check the pump motor for proper
operation (e.g., broken impeller,
pumping speed, leaking, sequence of
operation).
15. Check air filter, condenser fan blade,
and coil for dust, grease, and grime.
16. For ice flaker machines, check auger
and mechanical seals, and check
Semi-annual
Semi-annual
Annually, depending
on water conditions
Clear away as necessary.
Semi-annual
Clean in accordance with OEM
specifications (e.g., with soft brush,
coil cleaner, or vacuum with brush
attachment. Brush from top to
bottom, not side to side, so as not to
not bend fins).
Lubricate, repair (e.g., tighten,
weld, etc.), or replace as necessary.
Straighten with a fin comb as
necessary.
Clean water distribution system (by
hand) and evaporator (with
nicklesafe per OEM specifications)
as necessary.
Remove solids and flush
thoroughly, per OEM
specifications.
Repair or replace as necessary, per
OEM specifications.
Semi-annual
Clean as necessary.
Semi-annual
Replace as necessary.
Check with OEM
requirements (hrs. of
Semi-annual
Semi-annual
Semi-annual,
depending on water
conditions
Semi-annual
Semi-annual
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 21
auger bearings for water.
17. Check heat exchanger (evaporator)
surfaces for evidence of buildup or
fouling.
18. Check tubing for separation from
evaporator.
19. Check fan blades and fan housing for
dirt, bending, missing shroud.
20. With electric power on, check
condenser fan motor for proper
operation and integrity of bearings
(heat, vibration, noise).
21. Check air-cooled condenser surfaces
for damage or evidence of leaks.
Interior - Water
22. Check the water-cooled condenser
and water regulating valve for scale
buildup.
23. Check water distribution system and
evaporator for scale buildup.
24. Check water distribution system for
restrictions and consistent water flow
over the evaporator.
25. Check water flow through external
water filter.
26. Check strainer, inlet water valve
screen for obstruction or scale.
27. Check the float switch for scale.
28. Check the float valve assembly
adjustment and operation.
29. Check for proper drainage or water
backup in the bin.
30. Check for water overflow of the
reservoir.
31. Check drain pain, drain line, and coil
for biological growth.
32. Check interior panels and areas of
moisture accumulation for biological
growth.
Other
33. Check bins for contaminants.
34. Check bin ice sensor for proper
operation/location.
35. Determine ice production per 24
hours from OEM specifications and
compare to actual production.
Restore as necessary.
operation, time)
Semi-annual
Replace the evaporator.
Semi-annual
Clean, repair, or replace as
necessary.
Repair or replace as necessary.
Semi-annual
Repair, clean, or replace as
necessary.
Semi-annual
Clean per OEM specifications.
Semi-annual
Clean per OEM specifications.
Semi-annual
Clean as necessary.
Semi-annual
Remove and replace as necessary.
Semi-annual
Clean or replace as necessary.
Semi-annual
Clean or replace as necessary.
Clean, adjust, repair, or replace as
necessary.
Clean as necessary.
Semi-annual
Semi-annual
Identify cause of overflow, resolve,
and Clean as necessary.
Clean and sanitize as necessary, per
OEM specifications.
Clean and sanitize as necessary.
Semi-annual
Clean and sanitize the ice machine
bins per OEM instructions.
Adjust or replace as necessary.
Semi-annual
If production is low, perform
system check per OEM
specifications.
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 22
MAINTENANCE TASKS
Checklist 5.8 Industrial Refrigeration Built-Up Systems
Inspection Task
*
Rec. Corrective Actions
Evaporative Condenser – Water Circuit
1. Check spray distribution.
Clean and repair as necessary.
2. Check spray pump and piping.
Clean and repair as necessary.
3. Check the water treatment system.
Advise owner or representative if
not operational.
4. Check make-up water.
Clean strainer and repair as
necessary.
5. Check the bleed rate.
Clean strainer and adjust and repair
as necessary.
6. Check sump basin.
Clean, brush, and flush, must be
free of dirt and debris.
Evaporative Condenser – Motor and Drive
7. Check motor.
Lubricate and clean.
8. Check motor mounting.
Replace as necessary.
9. Check sheaves and pulleys.
Clean and repair or replace as
necessary.
10. Check gear drive unit (gear
Clean, repair and lubricate as
coupling/system).
necessary.
11. Check belts condition.
Replace as necessary.
12. Check belt tension and alignment.
Adjust or replace as necessary.
13. Check protective guards.
Ensure properly installed.
14. Check connection wiring (electrical
Tighten and secure.
whips).
15. Check motor volts and amperages.
Record values, advise owner or
representative if out of range.
Evaporative Condenser - Other
16. Check low ambient protection (basin Repair as necessary.
heater).
Open Drive, 100+ ton Compressor Package – Oil Circuit
17. Check operating time of unit.
Perform oil analysis, replace oil,
change oil filter and strainer per
recommended service interval.
18. Check the oil pump wiring and
Repair or replace as necessary.
starter, as applicable.
Compressor Package – Compressor Package
19. Check operating time of unit.
Replace coalescing element, suction
screen, liquid line strainers, and
motor compressor coupling per
recommended service interval.
20. Check for oil and refrigerant leaks.
Repair as necessary.
21. Check oil connections and LP/HP
If oil is found, check for refrigerant
control piping for oil leaks.
leaks or replace tubing as necessary
following OEM instructions.
Compressor Package - Controls
22. Check transducer calibration.
Re-calibrate as necessary.
23. Check RTD sensors.
Re-calibrate as necessary.
24. Check that the wiring properly
Support as needed.
*
Frequency
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Annually (with proper
water treatment)
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Annually (before
winter)
Quarterly
Annually
Quarterly
Quarterly
Annually
Quarterly
Quarterly
Quarterly
All corrective actions should be performed in accordance with the applicable OEM’s instructions. Corrective
actions which involve health and safety should follow the applicable food safety codes.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 23
supported.
25. Pull/download control data and
alarms.
26. Check for proper set points.
Compressor Package - Compressor
27. Check seal drip count.
28. Check compressor bearings.
29. Check motor wiring.
30. Inspect motor starter.
31. Check compressor unloading.
32. Check for loose compressor mounts.
33. (On semi-hermetic only) Check the
seals on all exposed gasket surfaces
for oil.
Various – Liquid Overfeed System
34. Check pump and motor performance.
35. Check pump motor starter and
wiring.
36. Check pump safety cut-off.
37. Check minimum flow device.
38. Check low side receiver fill valve.
39. Check evaporator feed valves.
40. Check general condition of piping
and insulation.
41. Check for piping refrigerant leaks.
Various Refrigerant Transfer Vessels
42. Check vessel integrity and insulation.
43. Check vessel transfer valves.
44. Check that valves operate in manual
mode.
45. Check vessel and piping for
refrigerant leaks.
Various - PLC
46. Check refrigerant monitor.
47. Check alarms.
48. Check outside communications
(alarm monitoring system, BMS).
49. Check alarm annunciator.
50. Check RTD Sensor calibration.
51. Check transducer calibration.
52. Check refrigerant monitor filter.
53. Check defrost and space temperature
set points.
54. Check auxiliary power supply.
Log, advise, and take appropriate
corrective action.
Quarterly
Correct settings.
Annually
Replace when drip count exceeds
OEMs drip count recommendation.
Adjust or replace as necessary.
Tighten connections as necessary.
Tighten connections as necessary,
replace contacts as necessary.
Inspect and adjust.
Repair or replace motor mounts as
necessary.
If oil is found, check for refrigerant
leaks or replace tubing as necessary
following OEM instructions.
Monthly
Check that it’s operating within
manufactures limits, if outside
determine cause and remedy.
Repair as necessary.
Monthly
Test and adjust.
Test and adjust.
Test proper cut in and cut out,
adjust.
Test for proper operation, repair or
replace as necessary.
Inspect, repair, replace as
necessary.
Repair, replace as necessary.
Monthly
Quarterly
Quarterly
Test and repair as necessary.
Test for proper operation, repair.
Test for proper operation, repair.
Quarterly
Quarterly
Quarterly
Test and repair.
Quarterly
Test and calibrate.
Test, log, and advise.
Test and advise.
Monthly
Monthly
Monthly
Test and repair.
Test and calibrate.
Test and calibrate.
Replace.
Test and adjust.
Quarterly
Annually
Annually
Annually
Annually
Test within date and charging,
repair or replace.
Annually
Quarterly
Quarterly
Quarterly
Quarterly
Annually
Annually
Monthly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 24
MAINTENANCE TASKS
Checklist 5.9 Parallel Rack Direct Expansion1,2
Inspection Task
Condenser
1. Check condenser for cleanliness.
2. Check power and control electrical
connections.
3. Check fans for proper rotation and
operation.
4. Check that refrigerant tubing
supports are secure.
Rack – Power Off
5. Check rack power and control
electrical connections (e.g., look for
frayed wire ends not fully under the
screw connections).
6. Check wiring for proper placement
and support.
7. Check for oil and refrigerant leaks.
8. Check cooling fans for control
cabinets and VFDs.
9. Check head cooling fan for proper
operation and cleanliness.
10. Record mega ohm (MΩ) value for
each compressor.
11. Check compressor mounting bolts
for proper tightness.
12. Check that refrigerant tubing
supports are secure.
Rack – Power On, System Running
13. Check refrigerant level in the
receiver or sight-glass, if system is so
equipped.
14. Check lubricant level at the reservoir.
15. Check lubricant level in the
compressor.
16. Check pressure drop across the
lubricant filter.
17. Check lubricant supply pressure.
18. Verify lubricant separator operation
and element pressure drop.
19. Check for excessive vibration.
20. Check compressor cooling devices
(demand cooling and head fans).
21. Check sub-cooler operation.
22. Check de-superheater operation.
23. Check defrost-pressure differential
valve operation.
24. Check outdoor ambient, discharge
Rec. Corrective Actions
Frequency
Clean as needed.
Repair or replace as needed.
Quarterly
Quarterly
Repair or replace as needed.
Annually
Secure and isolate as needed.
Annually
Tighten (one connector at a time),
repair, or replace as necessary.
Quarterly for aluminum
wiring
Annually for copper
wiring
Quarterly
Isolate and secure as needed.
Repair as needed.
Clean, repair, and replace as
needed.
Clean, repair or replace as
necessary.
Report inconsistencies if
applicable.
Adjust tightness per
manufacturer’s recommendation.
Secure and isolate as needed.
Quarterly
Semi-Annually
Compare to baseline level.
Quarterly
Record and compare to baseline
level.
Record and compare to baseline
level.
Replace if pressure drop exceeds
OEM limits.
Record and compare to baseline
level.
Clean and repair as necessary,
record element pressure drop,
replace the filter media if pressure
drop is excessive.
Repair and secure as needed.
Repair or replace as needed.
Quarterly
Adjust, repair or replace as needed.
Adjust, repair or replace as needed.
Adjust, repair or replace as needed.
Quarterly
Quarterly
Quarterly
Log results and compare to trends.
Quarterly
Annually
Annually
Annually
Annually
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 25
and suction temperatures, and
compressor amperage draw.
25. If existing, check BMS system’s
operation.
26. Check that all on-board control
devices are properly operating.
27. Check that rack controller is set for
optimum operation.
28. Take and test lubricant sample.
29. Check condenser flooding valves
(during periods of low ambient
temperatures).
30. Check split condenser controls and
valves (during periods of low
ambient temperatures).
31. Check compressor efficiency (use
manufacturer’s performance data).
32. Check that on-board pressure
transducers and temperature sensors
read correct.
Additional
33. Check crank case heaters for proper
operation.
34. Verify oil system is operating as
designed by checking oil separator
float for improper seating and blow
by, checking for excessive oil levels
in off cycle compressors, and
checking suction accumulators for
improper oil return through plugged
oil ports located in the internal piped
riser of the accumulator.
35. Check oil system return gas check
valves.
36. Check oil failure system deactivation
control.
37. Check the integrity of the fan blades;
note blades that do not match OEM
blades.
38. Check condenser control section for
evidence of water infiltration.
39. Check phase monitor settings, and
record the supply voltages.
If critical, determine the cause and
notify designated individual.
If any variation, notify the
designated individual.
If not working or found in override
position, notify designated
individual.
If there have been any alarms,
notify designated individual.
Resolve noted findings.
Adjust, repair or replace as needed.
Quarterly
Quarterly
Quarterly
Annually
Annually
Adjust, repair or replace as needed. Annually
Log results and compare to trends.
If critical, determine the cause and
notify designated individual.
Log results and compare to trends.
If critical, determine the cause and
notify designated individual.
Annually
Notify the designated individual if
the crank case heaters do not turn
off when the compressor is on or
the oil temperature is not at OEM
specifications.
Clean and repair the system as
necessary.
Quarterly
Replace if the return rate does not
meet OEM specifications.
Notify the designated individual if
the oil system safety switches are
not operating properly.
Replace as necessary. Notify the
designated individual if non-OEM
blades have been found.
If water infiltration is found,
replace seals as necessary and
notify the designated individual.
Notify the designated individual if
the setting has been changed
between inspections.
Quarterly
Annually
Quarterly
Quarterly
Quarterly
Quarterly
Semi-Annually
Notes:
1. If, during the course of regular maintenance, the technician notices that the transducers are
mounted incorrectly (horizontally), they should notify the owner of this incorrect installation.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 26
MAINTENANCE TASKS
2. During the course of regular maintenance inspection, the technician may notice unusual
vibrations, which may be transmitted through the system piping. This type of vibration may be
the result of improperly design/balanced piping systems, discharge restrictor plates that have been
removed, or failed mufflers; the vibration can result in brazed joints being compromised. The
technician should report these vibrations to the owner.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 27
Checklist 5.10 Reach-In1
Inspection Task
Rec. Corrective Actions
Frequency
Clean as necessary per
manufacturer’s specifications.
Clean or replace as necessary.
Remove light build-up with a brush
or a vacuum with a brush
attachment.
Remove moderate buildup with
compressed air, followed by
brushing as necessary.
Remove heavy buildup per
manufacturer’s specifications.
Clean as necessary.
If washing the fan blades is
necessary, cover the fan motor to
prevent moisture damage.
Clean the louvers on the
downstream side of the condenser
and/or gravity dampers if
applicable.
Ensure sure that the fan shroud is
present and intact.
Straighten with fin comb as
necessary.
Monthly
Ensure it is level and trapping.
Connect drain tube to evaporator
drain pain as necessary.
Remove drain tube obstructions as
necessary.
Replace heater if amperage does not
meet manufacturer’s specifications.
Clean with a brush or soapy water
as necessary.
Straighten fins or replace
evaporator coil if necessary.
Remove any obstructions that block
air to the evaporator.
Quarterly
Quarterly
Adjust the knob until the time
matches the manufacturer’s
specification.
Adjust until it matches the
manufacturer’s specified set point.
Quarterly
Replace broken guides as
necessary.
Clean with mild soap and water
solution as necessary. Follow with
fresh water rinse.
Quarterly
2
Condenser
1. Check condenser coil surface for
dust, dirt, and lint.
2. Check condenser intake air filter.
3. Shine a light on the condenser
surface to check for dirt inside the
condenser.
4. Check fan blades and motor for
cleanliness.
5. Check condenser for adequate
airflow and no recirculation of
discharge air.
6. Check condition of fins as
applicable.
Evaporator Coil
7. Check drain trap.
8. Check drain tube.
9. Check self-contained water removal
system (condensate drain pan).
10. Check for dirt, build-up, and foreign
objects.
11. Check the integrity of fins.
12. Check for obstructions to proper
airflow.
Controls
13. Check operation defrost control set
time.
14. Check case temperature set point.
Doors/Gaskets
15. Check door slides or guides.
16. Check door gaskets for cleanliness
and presence of mold or mildew.
Monthly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 28
MAINTENANCE TASKS
17. Check door gaskets for proper
sealing.
18. Check door hinges for looseness.
19. Check amperage of anti-sweat,
frame, and door heaters.
Walls/Panels/Interior
20. Check refrigeration tubing is not
rubbing or vibrating against other
tubing or panel.
21. Check cabinet exterior and interior
for cleanliness.
22. Check casters for corrosion.
23. Check insulation and areas of
moisture accumulation for biological
growth.
24. Check condition of shelves.
Surroundings
25. Check for anything stacked on or
around the machine.
26. Check area surrounding the machine
for cleanliness.
Adjust or replace as necessary.
Quarterly
Tighten the screws that mount the
hinge brackets to the unit frame as
necessary.
Replace broken hinges as
necessary.
Replace if amperage does not meet
manufacturer’s specifications.
Quarterly
Correct as necessary.
Quarterly
Clean with mild soap and water
solution as necessary. Follow with
fresh water rinse.
Wipe with damp cloth as necessary.
Lubricate per manufacturer’s
specifications.
Clean or disinfect as necessary.
Quarterly
Clean as necessary.
Quarterly
Advise customer to remove as
necessary.
Advise customer to clean as
necessary.
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Notes:
1. Reach-ins can be self-contained, a part of a parallel rack, or a remote condenser.
2. Disconnect electric power before cleaning.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 29
Checklist 5.11 Service Over Counter (Reach-In)
Inspection Task
Rec. Corrective Actions
Frequency
Clean as necessary per
manufacturer’s specifications.
Clean or replace as necessary.
Remove light build-up with a brush
or a vacuum with a brush
attachment.
Remove moderate buildup with
compressed air, followed by
brushing as necessary.
Remove heavy buildup per
manufacturer’s specifications.
Clean as necessary.
If washing the fan blades is
necessary, cover the fan motor to
prevent moisture damage.
Clean the louvers on the
downstream side of the condenser
and/or gravity dampers if
applicable.
Ensure sure that the fan shroud is
present and intact.
Straighten with fin comb as
necessary.
Monthly
Replace if excessive.
Ensure it is level and trapping.
Connect drain tube to evaporator
drain pain as necessary.
Remove drain tube obstructions as
necessary.
Replace heater if amperage does not
meet manufacturer’s specifications.
Clean with a brush or soapy water
as necessary.
Replace evaporator coil if
necessary.
Remove any obstructions that block
air to the evaporator.
Quarterly
Quarterly
Quarterly
Adjust the knob until the time
matches the manufacturer’s
specification.
Adjust until it matches the
manufacturer’s specified set point.
Quarterly
Replace broken guides as
necessary.
Clean with mild soap and water
solution as necessary. Follow with
Quarterly
1
Condenser
1. Check condenser coil surface for
dust, dirt, and lint.
2. Check condenser intake air filter.
3. Shine a light on the condenser
surface to check for dirt inside the
condenser.
4. Check fan blades and motor for
cleanliness.
5. Check condenser for adequate
airflow and no recirculation of
discharge air.
6. Check condition of fins as
applicable.
Evaporator Coil
7. Check the coil for pitting2.
8. Check drain trap.
9. Check drain tube.
10. Check self-contained water removal
system (condensate drain pan).
11. Check for dirt, build-up, and foreign
objects.
12. Check the integrity of fins.
13. Check for obstructions to proper
airflow.
Controls
14. Check operation defrost control set
time.
15. Check case temperature set point.
Doors/Gaskets
16. Check door slides or guides.
17. Check door gaskets for cleanliness
and presence of mold or mildew.
Monthly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 30
MAINTENANCE TASKS
18. Check door gaskets for proper
sealing.
19. Check door hinges for looseness.
20. Check amperage of anti-sweat,
frame, and door heaters.
Walls/Panels/Interior
21. Check refrigeration tubing is not
rubbing or vibrating against other
tubing or panel.
22. Check cabinet exterior and interior
for cleanliness.
23. Check casters for corrosion.
24. Check insulation and areas of
moisture accumulation for biological
growth.
25. Check condition of shelves.
Surroundings
26. Check for anything stacked on or
around the machine.
27. Check area surrounding the machine
for cleanliness.
Additional
28. Check doors/drawers for proper fit.
29. Check refrigerant line insulation.
fresh water rinse.
Adjust or replace as necessary.
Quarterly
Tighten the screws that mount the
hinge brackets to the unit frame as
necessary.
Replace broken hinges as
necessary.
Replace if amperage does not meet
manufacturer’s specifications.
Quarterly
Correct as necessary.
Quarterly
Clean with mild soap and water
solution as necessary. Follow with
fresh water rinse.
Wipe with damp cloth as necessary.
Lubricate per manufacturer’s
specifications.
Clean or disinfect as necessary.
Quarterly
Clean as necessary.
Quarterly
Advise customer to remove as
necessary.
Advise customer to clean as
necessary.
Quarterly
Adjust as necessary.
Repair or replace as necessary.
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Notes:
1. Disconnect electric power before cleaning.
2. It is especially important if vinegar products are kept in the unit.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 31
Checklist 5.12 Single Condensing Unit
Inspection Task
Rec. Corrective Actions
Frequency
Clean as needed.
Repair or replace as necessary.
Quarterly
Quarterly
Repair or replace as necessary.
Follow OEM’s specifications for
torque tolerances and tightening,
as applicable.
Secure and isolate as necessary.
Quarterly
Repair as necessary.
Quarterly
Replace driers if moisture is
indicated.
If low determine cause, correct and
add oil.
Evaluate that temperatures are in
proper range, if out determine
cause and advise owner of needed
repairs.
Evaluate that amperes, voltage,
and voltage balance are in proper
range, if out determine cause and
advise owner of needed repairs.
Adjust or repair as necessary.
Quarterly
Adjust or repair as necessary.
Quarterly
Install covers and panels as
necessary.
Quarterly
Clean as necessary.
Clean as necessary with NSFapproved cleaner.
Quarterly
Quarterly
Repair or replace as necessary.
Quarterly
Adjust or replace as necessary.
Quarterly
Repair or replace as necessary.
Follow OEM’s specifications for
torque tolerances and tightening,
as applicable.
Repair or replace as necessary.
Quarterly
Repair as necessary.
Quarterly
Adjust or replace as necessary.
Quarterly
1
Condenser/Compressor Section
1. Check condenser for cleanliness.
2. Check condenser fans for proper
operation.
3. Check power and control electrical
connections.
4. Check that refrigerant tubing
supports are secure.
5. Check for indication of refrigerant
leaks (i.e., oil spot, sight glass, etc.).
6. Check refrigerant moisture indicator.
7. Check compressor oil level, as
applicable.
8. Check suction and discharge
temperatures per OEM specification.
9. Check compressor amperes, voltage,
and voltage balance.
10. Check all compressor operating
controls (e.g., low-ambient control)
and safety controls.
11. Check defrost controls.
12. Check that electrical covers and
panels are in properly installed.
Evaporator Section
13. Check evaporator for cleanliness.
14. Check evaporator drain pan and
drain lines for cleanliness and proper
draining.
15. Check evaporator fans for proper
operation.
16. Check for proper fan (e.g. fan delay
control) and temperature control
operation.
17. Check power and control electrical
connections.
18. Check evaporator defrost
components for proper operation.
19. Check for indication of refrigerant
leaks.
20. Check expansion device for proper
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 32
MAINTENANCE TASKS
operation.
21. Check that electrical covers, panels
and trim are properly installed.
Refrigerant Line Set
22. Check the hangars and supports for
proper and secure installation.
23. Check for torn or missing insulation.
24. Check for indication of refrigerant
leaks.
Install covers and panels as
necessary.
Quarterly
Repair defective supports.
Quarterly
Repair and/or replace insulation as
necessary.
Repair as necessary.
Quarterly
Quarterly
Notes:
1. Any time the system is opened, replace the dryer or dryer cores.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 33
Checklist 5.13 Soft Serve Machines1
Inspection Task
Exterior
1. Check that the refrigeration tubing is
not rubbing or vibrating against other
tubing or panels.
2. Check refrigeration tubing insulation.
3. Check that nothing is stacked on or
around the machine which impedes
appropriate airflow through and
around machine per OEM
specifications.
4. Check for dust and dirt on the
outside of the machine.
Rec. Corrective Actions
Frequency
Adjust as necessary.
Semi-annual
Replace or repair as necessary.
Clear away as necessary.
Semi-annual
Semi-annual
(daily)
Sponge off with mild soap and
water, then dry with a soft, clean
cloth. Commercial stainless steel
cleaner may be used if applicable.
5. Check the integrity of all panels and
Replace fasteners as needed to
supports on equipment, as applicable. ensure proper integrity and
fit/finish.
Interior - Mechanical
6. Check the air filter for dust, grease,
Clean as necessary.
and grime.
7. Check drive belts for wear.
Replace belts as necessary.
8. Check condenser for adequate
Clear away or move the machine as
airflow, and intake and ambient air
necessary.
temperature2 for recirculation of
discharge air, per OEM
specifications.
9. Disconnect electric power and check Clean in accordance with OEM
the outside of condenser and fins for specifications (e.g., with soft brush,
dirt.
coil cleaner, or vacuum with brush
attachment. Brush from top to
bottom, not side to side. Be careful
in order to not bend fins).
10. Check the condenser fan motor for
Lubricate, repair (e.g., tighten,
worn bearings and secure mounting.
weld, etc.), or replace as necessary.
11. Check condenser fan blade and coil
Clean as necessary.
for dust, grease, and grime.
12. Check fan blades and fan housing for Clean, repair, or replace as
dirt, bending, missing shroud.
necessary.
13. With electric power on, check
Repair or replace as necessary.
condenser fan motor for proper
operation and integrity of bearings
(heat, vibration, noise).
14. Check air-cooled condenser surfaces Straighten, repair, clean, or replace
for damage (e.g., bent fins) or
as necessary.
evidence of leaks.
15. Check O-rings for wear, tear, and
Replace with new ones as
loose fit.
necessary.
16. Check the scraper blades for damage. Replace scraper blades that are
nicked or damaged.
17. Check the shell bearing for signs of
Clean and lubricate following all
Semi-annual
(daily)
Semi-annual
Monthly
Quarterly
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
Semi-annual
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 34
MAINTENANCE TASKS
wear (excessive mix leakage in drip
pan) and be certain it is properly
cleaned.
18. Check drive belt tension.
19. Check the type of lubricant being
used.
Cleaning and Sanitizing
20. Review operator’s sanitation
policies.
lubricating procedures as outlined
in OEM manual.
Adjust, as necessary, following the
steps in the operator’s manual.
Verify that the lubricant used is in
accordance with US Department of
Agriculture, FDA, and OEM
requirements. Notify equipment
owner if not.
Semi-annual
Notify them that sanitation must
comply with federal, state, and local
regulations and codes. Machine
must be sanitized after service.
Quarterly
Semi-annual
Notes:
1. Ambient conditions of machine operation must comply with applicable codes, regulations, and OEM
specifications.
2. These two temperatures should be equal or near equal.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 35
Checklist 5.14 Walk-In
Inspection Task1
Condensing Unit
1. Check air-cooled condenser surfaces
for damage or evidence of leaks (oil
spots).
2. Check for signs of oil stains on
interconnection piping and condenser
coil, paying close attention to areas
around solder joints, building
penetrations, and pipe clamps. If a
suspect area is found, check with an
electronic leak detector.
3. Check condition of outdoor
condensing units.
4. Check any suspect areas with an
electronic leak detector.
5. Check the condition of the
condenser, looking for accumulation
of dirt and debris.
6. Check for corrosion issues.
7. Check all mechanical and flare
connections.
8. Check compressor oil levels and oil
safeties.
9. Check compressor sight glass (if
equipped) for proper oil level.
10. Check net oil pressure, operating at
manufacturer’s design.
11. Measure compressor superheat to
verify that it conforms to
specification.
12. Check low ambient head pressure
control sequence for proper
operation.
13. Check motors for proper lubrication,
if applicable.
14. Check for proper operation of
cooling coil, and for damage or
evidence of leaks.
15. Check condenser coil and blades
cleanliness
16. Check operation of demand cooling,
liquid injection, or unloaders, if so
equipped.
17. Check high and low pressure
refrigerant control settings and verify
proper operation.
18. Check pressure drop across all
refrigerant filters and driers.
Rec. Corrective Actions
Frequency
Repair or clean as needed.
Quarterly
Repair any leaks found and add
refrigerant as needed.
Quarterly
Clear away weeds and debris as
necessary.
Repair as necessary
Quarterly
Clean as required.
Quarterly
Apply anti-corrosion primer and
paint as required.
Tighten as necessary.
Quarterly
Repair, replace, or adjust as needed
to ensure proper operation.
Adjust oil levels as needed.
Quarterly
Repair, replace, or adjust as needed
to ensure proper operation.
Adjust as needed.
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Repair or replace components, or
Quarterly
modify software/set points to ensure
proper operation.
Lubricate as necessary. Do not
Quarterly
lubricate permanently sealed, ball
bearing motors.
Clean, restore, or replace as
Quarterly
required.
Clean as necessary.
Quarterly
Repair, replace, or adjust as
necessary.
Quarterly
Replace or adjust as necessary.
Quarterly
Replace as required.
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 36
MAINTENANCE TASKS
19. Check refrigerant levels in the sight
glass and inspect for leaks.
20. Check refrigerant system
temperatures.
21. Check suction lines for insulation
decay between condensing unit and
evaporator coil.
22. Check the amperage of motors and
compressors.
23. If the accumulator is insulated, check
for damage.
24. Check the refrigerant piping
penetrations for air or water leaks or
rubbing against other piping.
25. Measure crankcase heater amp draw
to verify operation.
26. Check condition of moisture
indicator/sight glass if so equipped.
27. Check moisture indicator/sight glass
for flash gas. If found, check entire
system for refrigerant leaks.
Evaporator Fan Coil/Unit Cooler
28. Check condensate line.
29. Check drain line heat tape for proper
operation.
30. Check drain pan to ensure that drain
is clear of debris, obstructions, or ice
buildup and is free draining.
31. Check for condensate water dripping
on the walk-in floor, or moisture
carryover beyond the drain pan from
the cooling coils
32. Check drain pan, drain line, and coil
for biological growth.
33. Check motors for proper lubrication,
if applicable.
34. Check all fan blade set screws and all
fan guards are in place.
35. Check all fan blades and motor
housing/rail for signs of cracks,
wear, or stress. Pay close attention
to the hub and spider.
36. Check for unusual noise or vibration.
37. Check operation of all fans to ensure
airflow is unobstructed.
38. Check all flare connections.
39. Check evaporator coil fins surfaces.
40. Check for proper defrosting of
evaporator. Check operation /
calibration of all fan cycle and
defrost controls when used.
Adjust as necessary and document
for future visits.
If outside of recommended levels,
find cause, repair as necessary, to
achieve optimal operating levels.
Replace as necessary.
Quarterly
Document for future visits, find
cause for difference from
manufacturer’s design.
Clean, restore, seal, or replace as
necessary.
Repair as needed.
Quarterly
Repair or replace as needed.
Quarterly
If there is indication of moisture
(out of range), replace driers.
Repair any leaks and add refrigerant
as needed.
Quarterly
Ensure drain line has no blockage.
Repair or replace as necessary.
Quarterly
Quarterly
Clear as necessary.
Quarterly
Find the source and correct the
problem.
Quarterly
Clean as needed.
Quarterly
Lubricate as necessary. Do not
lubricate permanently sealed, ball
bearing motors.
Tighten as required or replace as
necessary.
Replace blades or housing as
required.
Quarterly
Take corrective action as required.
Remove obstruction.
Quarterly
Quarterly
Tighten as necessary.
Clean as necessary.
Determine the cause and correct.
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
MAINTENANCE TASKS
PAGE 37
41. Check for abnormal accumulation of
ice patterns.
42. Compare actual defrost heater
voltage and amp draw against unit
data plate.
43. Check condensate drain P-trap if
present.
44. Check for oil stains on heaters, return
bend, and coil fins.
45. Check for signs of corrosion on fins,
cabinet, copper tubing, and solder
joints.
46. Visually inspect heaters to ensure
even surface contact with the coil.
Electrical Controls
47. Check all wiring and connections for
overheating, bare spots, kinks.
48. Check condition of compressor and
defrost contactors. Look for
discoloration and pitting.
49. Check control box for dirt, debris,
insects and/or loose terminations.
50. Check operation and calibration of
all timers, relays, pressure controls,
temperature controls, and safety
controls.
51. Check electrical covers on the walkin’s evaporator coils blower unit.
Doors/Gaskets
52. Check for frost or condensation
around the door jamb or heated
pressure relief vent.
53. Check hinges and door closers for
proper opening.
54. Check to make sure that the doors
are sealing tightly. Check sweeps.
55. Check condition and operation of
strip curtains.
56. Check the door gaskets.
Walls/Panels/Interior
57. Check all electrical connection.
58. Check integrity of all panels and
curbs on equipment.
59. Check interior for cleanliness.
60. Inspect the condition of anti-skid
strips on ramps and thresholds.
61. Check caulk seals in wall joints.
Adjust defrost cycles or operation
of expansion valve/superheat
accordingly.
Repair or replace.
Quarterly
Prime as needed to ensure proper
operation.
Repair or clean as needed.
Quarterly
Repair as necessary.
Quarterly
If heaters have warped. Re-align or
replace heaters as needed.
Quarterly
Repair or replace as necessary.
Quarterly
Replace as required.
Quarterly
Clean and tighten as needed.
Quarterly
Adjust or replace as necessary.
Quarterly
Replace if missing.
Quarterly
Replace heaters as necessary.
Quarterly
Lubricate as necessary.
Quarterly
Adjust as necessary.
Quarterly
Inform owner if missing or
damaged.
Replace as necessary. Clean them
with a soft cloth, soap, and water.
Quarterly
Tighten as necessary.
Replace fasteners as needed to
ensure proper integrity and fit/finish
of equipment.
Clean the interior of the walk-in
cooler as necessary; avoid using
harsh cleaners.
Replace as necessary.
Quarterly
Quarterly
Repair as necessary.
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Quarterly
Notes:
1. During the course of regular maintenance inspection, the technician may notice that the outdoor condenser
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 38
MAINTENANCE TASKS
was not installed at the proper, minimum height above grade (or roof, as applicable) with regard to local
building code requirements. The technician should report this installation fault to the owner.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX A – DEFINITIONS
PAGE 39
APPENDIX A – DEFINITIONS
[This Appendix is not part of the standard. It is merely informative and does not contain
requirements necessary for conformance to the standard. It has not been processed according to the
ANSI requirements for a standard and may contain material that has not been subject to public review
or a consensus process. Unresolved objectors on informative material are not offered the right to
appeal at ACCA or ANSI.]
Absorption System: A refrigeration system in which the refrigerant gas evolved in the evaporator is
taken up in an absorber and released in a generator upon the application of heat.
Accumulator: A tank installed in the suction line on or near the compressor unit, designed to intercept
liquid refrigerant before it can reach the compressor crankcase. Liquid trapped in the accumulator is then
returned at a safe rate back to the compressor. On parallel compressor systems, the suction manifold is
designed to serve this function. It also meters lubricant to the compressor on start-up.
Air Curtain: A moving blanket of air blown across the opening of a refrigerated merchandiser which
allows reach-in customer access while reducing the exchange of refrigerated air with ambient air.
Air Defrost: Suitable for all medium temperature display cases and walk-ins with room temperatures
above 34°F. Defrost is accomplished either by leaving fans on and stopping refrigeration for a specified
length of time, or as a natural result of cycling the refrigeration by means of a thermostat or low pressure
control. See "off time" defrost.
Ambient Air: The air surrounding an object. The air around a refrigeration system condenser is typically
considered "ambient air.
Ambient Sub-cooling: Sub-cooling in the condenser by the use of the ambient air to cool the refrigerant
lower than the saturated condensing temperature.
Anti-sweat Heater: A self-regulating low-amp draw electric heater, installed to prevent condensation
where metal surfaces are cooled below expected dew point by the refrigeration process. Anti-sweat
heaters are most used on low temperature merchandisers. Types of anti-sweat heaters: door, frame,
discharge nosing, return nosing, rear cap, rear overhang.
Automatic Water Regulating Valve: A form of winter condensing pressure control for water cooled
condensers. It restricts the flow of water if discharge pressure drops below a pre-set minimum.
Ball Valve: A manually operated valve to stop the flow of refrigerant, or isolate a section of the system.
Allows for ease in servicing, and provides no pressure drop if full-port valves are used. A minimal
pressure drop will be realized if non full-port valves are used. Standard on Hussmann parallel rack
suction, liquid and defrost branches.
Cascade System: A refrigeration system with two or more refrigerant circuits, each with the evaporator
of one cooling the condenser of the next, in series, to achieve very low temperatures.
Check Valve: Permits flow in one direction only. Used when possible backflow would be detrimental to
the system.
Circuit System: A supermarket refrigeration system design type that includes a separate liquid line and
suction line for each case or line-up of cases. When contrasted with the loop system, it is more difficult to
install but more convenient to service. Contrasts with Loop System.
Coil: The finned copper or aluminum tube assembly used for heat transfer in refrigerators (evaporator
coil), in condensers (condenser coil), and for heat reclaim (heat reclaim coil).
Compressor: In refrigeration, the machine that compresses the cool refrigerant into a hot, high pressure
gas so it can give off heat to the air or water being passed through a condenser.
Compressor Burn-Out: Catastrophic compressor failure due to excessive heat and/or lubrication failure
which results in motor winding insulation failure.
Condensation: The process of changing vapor into liquid by extracting heat.
Condenser: The device that exhausts the heat from a refrigeration system. The refrigerant turns from a
gas into a liquid in the condenser, and is ready to begin the refrigeration cycle again. Condensers can be
air-cooled, water-cooled or a combination of both, called evaporative condensers or fluid coolers.
Condensers may also be single circuited, multi circuited, or split-circuited.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX A – DEFINITIONS
Page 40
Condenser, Air-Cooled: A condenser cooled by natural convection air currents or by forced air
circulation.
Condenser, Evaporative: A condenser cooled by the evaporation of water.
Condenser, Water-Cooled: A condenser cooled by water circulated through it.
Condensing Temperature: Temperature at which refrigerant vapor gives up its latent heat of
vaporization and becomes a liquid. May also refer to the temperature used in sizing a condenser.
Contactor: An electrically controlled switch used for switching a power circuit, similar to a relay except
with higher current ratings.
Copper Plating: An undesirable film of copper deposited on compressor walls, pistons, discharge valves,
motor shaft, or seals. This condition is not normal and may occur when excessive temperatures are seen.
Crankcase Heater: A device that inserts into, mounts under, or wraps around the compressor crankcase
and warms it to prevent liquid refrigerant from accumulating in the compressor when the off cycle
compressor is exposed to cold temperatures. On Hussmann compressor units, the crankcase heaters turn
on when the compressor turns off. Crankcase heaters are standard on some compressors, but, if not, are
recommended options for compressor units subjected to environments of 45°F and below.
Defrost: Any method of removing frost or ice from an evaporator.
Demand Cooling: A compressor head cooling system which injects saturated refrigerant into the suction
cavity when the head temperature exceeds a safe operating level.
Differential Check Valve: A spring loaded check valve that permits flow only when the outlet pressure
is a pre-determined amount lower than the inlet pressure.
Differential Pressure Regulator: A regulating valve that maintains a constant differential used in
reverse flow defrost and head pressure bypass.
Discharge Air Temperature: The temperature of the air immediately after it leaves the evaporator or
condenser coil.
Discharge Pressure: The pressure of the refrigerant measured in pounds per inch, gauge (psig), as it
leaves the discharge valve of the compressor; the pressure of the refrigerant anywhere between the
compressor and condenser.
Discharge Pressure Control: Winter condensing, or high pressure cut-out control.
Evaporative Cooling: A device designed to cool a space by passing air through a water spray or wetted
surface and using the cooling effect of evaporation to reduce the air temperature. This device works well
when relative humidity is low.
Evaporator: The device that extracts heat from a refrigerator. When refrigerant enters the evaporator
through the expansion valve, its pressure is reduced to the point where the heat in the refrigerator is
sufficient to make the refrigerant boil. As the refrigerant boils (evaporates rapidly) it draws heat from the
refrigerator in much the same way as perspiration does from the body.
Evaporator (Evaporation) Temperature: A common term for the saturated suction temperature. Also,
saturated suction temperature usually refers to the temperature equivalent of the pressure measured at the
suction valve of the compressor rather than at the evaporator.
Evaporator Pressure Regulator: A modulating temperature control valve installed in the suction line of
a compressor unit that can be set to maintain a fixed evaporator pressure (hence temperature). EPR's are
used extensively on parallel compressor units to raise the evaporator temperature in the warmer
refrigerators connected to the compressor unit.
Fan-Cycling Control: A form of winter condensing pressure control in which condenser fans are turned
off as ambient temperature decreases. Either thermostats (sensing ambient air) or pressure controls
(sensing condensing pressure) can be used to make and break the fan circuit. Also used in some meat
cases while on gas defrost.
Floating Head: To allow head pressure to “float” in low ambient conditions to save energy.
Flooded Coil: A condition caused by passing more refrigerant through an evaporator coil than can be
vaporized at the immediate temperature and pressure. See Frost Back.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX A – DEFINITIONS
PAGE 41
Flooding Valve: A form of winter condensing pressure control consisting of an upstream regulator in the
liquid return line from the condenser. If condensing pressure decreases in response to colder weather, the
valve throttles, causing liquid refrigerant to back up in the condenser until condenser capacity decreases
enough to return condensing pressure to the setting of the valve.
Frost Back: The condition of frost (frozen moisture) on the outside of the evaporator outlet and suction
line as a result of incomplete vaporization of refrigerant in a "flooded" evaporator. See Flooded Coil.
Head Cooling Fan: A fan mounted on low temperature compressors which cycles with the compressor.
The fan provides airflow over the head to remove excessive heat of compression which would damage the
head or cause oil breakdown.
Head Pressure: The pressure on the high side of a refrigeration system, measured in the discharge line at
the outlet of the compressor.
Head Pressure Control: Winter condensing pressure control accomplished by various methods to
include: 1) cycling of condenser fans; 2) air damper controls; 3) flooding valve; 4) split condenser.
Heat Exchanger: Device used to transfer heat from a warm or hot surface to a cold or cooler surface.
Heat of Compression: Mechanical energy expelled as heat energy when a vapor is compressed.
Heat of Condensation: Latent heat released when a vapor changes to a liquid due to a change in
temperature or pressure.
Heat Reclaim: The heat normally rejected into the outside air by the condenser is used inside the store
for heating purposes. The heat may be prioritized for hot water, or hot air for the store, or back room.
Heat, Latent: Heat characterized by a change of state of the substance concerned, for a given pressure
and always at a constant temperature of a pure substance, i.e., heat of vaporization, or of fusion.
Heat, Sensible: Heat which is associated with a change in temperature as contrasted to heat interchange
in which a change of state occurs.
High Pressure Control or Cutout: A pressure sensitive device (usually an electric switch), actuated
directly by the refrigerant vapor pressure on the high side (usually head pressure).
Liquid Injection: Used on compound systems to maintain proper superheat levels entering the second
stage compressors.
Liquid Level Indicator: Device located in the liquid line and having a sight port by which liquid flow
may be observed for the presence of bubbles.
Liquid Solenoid Valve: A solenoid valve used to control the flow of refrigerant in a liquid line.
Loop System: A supermarket refrigeration system design type that includes a single liquid line and
suction line serving many cases, each case having its own liquid line solenoid (LLS) and evaporator
pressure regulator (EPR). When contrasted with the circuit system, it is easier to install but more difficult
to service. Contrasts with Circuit System.
Main Liquid Line Solenoid: On parallel compressor units, this valve restricts liquid refrigerant flow,
reducing pressure to all branch liquid line solenoids when any system goes on gas defrost. This allows
backflow of liquid refrigerant from the evaporator(s) being defrosted into the liquid manifold for use in
systems still in refrigeration mode.
Motorized Ball Valve: A motor-driven shut-off valve that can be remotely controlled by a
microprocessor control or other means.
Off Time Defrost: Defrost occurring when the defrost time clock closes the system liquid line valve in
order to stop refrigerant flow. The resultant lack of refrigerant defrosts the merchandiser. Off time will
vary per merchandiser.
Oil Failure Safety Control: On compressors equipped with an oil pump for lubrication, this safety
control senses the difference in pressure between the intake and discharge of the pump. If this difference
falls and remains below the setting of the control for a minute or two, the control will trip, de-energizing
the compressor motor contactor. The control must be manually reset.
Oil Float: The device used to meter oil into compressor crankcases on parallel compressor units and their
satellites. Also called "oil regulators," or "oil level regulators."
Oil Reservoir: A tank that supplies oil to the oil floats on parallel compressor units.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX A – DEFINITIONS
Page 42
Oil Separator: A device located in the discharge line of compressor units that captures much of the oil
pumped out of the compressors to minimize the quantity of oil circulating through the refrigerant lines.
Oil separators are standard on parallel compressor units, and return the oil to the oil reservoir. They are
available for Conventional units, and return the oil to the suction side of the compressor.
Preparation Area (Prep Room): Often called a "prep room". A large, refrigerated work area where
vegetables or meats are processed and packaged for display and sales purposes.
Pressure Relief Device: A valve or rupture device designed to automatically relieve excessive pressure.
Receiver Pressure Regulating Valve: Used with a flooding valve, this valve permits discharge gas to
flow to the receiver to ensure sufficient receiver pressure.
Refrigerant Recovery: To remove refrigerant from a system and transfer it to an approved refrigerant
container.
Relay: An electrically operated switch. Relays are used where it is necessary to control a circuit by a lowpower signal (with complete electrical isolation between control and controlled circuits), or where several
circuits must be controlled by one signal.
Satellite: A separate compressor unit that uses the same source of refrigerant as the parallel compressor
unit it is applied to. Satellites can be remote, or installed on a parallel compressor unit and are available
for both medium and low temperature applications. Applied to the lowest temperature refrigerators, (low
end Satellite), the Satellite permits the parallel compressors to operate at a higher, more efficient suction
pressure. Satellites are often applied to preparation areas (high end Satellites) to decrease the required
capacity of the parallel compressor unit.
Saturated Suction Pressure: The suction pressure at which liquid refrigerant will boil at a specified
temperature. The lower the saturated suction pressure, the colder this boiling point becomes, and the
colder the evaporator will be.
Saturated Suction Temperature: The evaporator temperature that corresponds to the saturated suction
pressure. Evaporator temperature.
Secondary Fluid: A heat transfer fluid that is used to transfer heat from a space or product that does not
change state (liquid-gas or gas-liquid). Usually a mixture of glycol and water, but may be other fluids.
Self-Contained: A fully charged merchandiser equipped with its own condenser unit, which can operate
independently of another refrigeration system.
Split Condenser: A doublewide condenser with each side operating independently of the other, and each
having its own fan controls. Used to reduce the amount of refrigerant required for operation in low
ambient conditions.
Split Suction: Two suction groups on one compressor rack.
Sub-cooling: Heat rejection by refrigerant liquid. Sub-cooling can be viewed as the temperature of the
refrigerant below its condensing point at its immediate pressure. A small amount of sub-cooling is
necessary to prevent flash gas or bubbles in the liquid line which results in poor refrigerator performance.
Suction Filter: A filter used in the suction line between the evaporator pressure regulating valve and the
compressor.
Suction Manifold: The inlet to the compressor from the low (suction) side designed to trap liquid
refrigerant before it can reach the compressor.
Superheat: Heat absorbed by refrigerant vapor. Superheat can be viewed as the temperature of the
refrigerant above its boiling point at its immediate pressure.
Thermostatic Expansion Valve (TEV or TXV): Valve that allows expansion and boiling of refrigerant
from liquid to vapor.
Three Way Valve: A solenoid valve with an inlet which is common to either of two opposite outlets, or
with a common outlet and two opposite inlets. Three way valves control refrigerant direction.
Unit Cooler: The evaporator and fan assembly that provides the refrigeration for a walk-in or preparation
area. Often called a blower coil, it consists of an evaporator coil, expansion valve, and fan(s).
Unloader (external): A solenoid which holds open one intake valve of a multi-piston compressor. This
reduces the load the compressor can pump unloads reducing refrigeration capacity.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX A – DEFINITIONS
PAGE 43
Unloader (internal): A hydraulic mechanism which holds open the intake valve(s) until oil pressure
reaches a set point. This assures oil is circulating before the compressor starts pumping.
VFD: Variable Frequency Drive.
Winter Condensing Pressure Control: During cold weather, heat reclaim, or gas defrost, the condenser
of a refrigeration system will work too well. Unchecked, its capacity can increase to the point where
liquid line pressures are too low to operate the thermostatic expansion valves, and the refrigerators will
warm up. To prevent this, several forms of condensing pressure control can be used to maintain a
minimum condensing pressure.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX B – BIBLIOGRAPHY & RESOURCES
Page 44
APPENDIX B – REFRIGERATION BIBLIOGRAPHY & RESOURCES
[This Appendix is not part of the Standard. It is merely informative and does not contain
requirements necessary for conformance to the Standard. It has not been processed according to the
ANSI requirements for a standard and may contain material that has not been subject to public review
or a consensus process. Unresolved objectors on informative material are not offered the right to
appeal at ACCA or ANSI.]
The following documents are offered for informational purposes only and are not considered part of the
requirements of this standard. The editions/versions/dates of the documents indicated here are current as
of the date of this ACCA standard.
ACCA
Air Conditioning Contractors of America (2800 Shirlington Road, Suite 300,
Arlington, VA, 22206; tel: 703/575-4477; www.acca.org)
– EPA Refrigerant Certification (Section 608)
– Understanding Section 608 DVDs
– Refrigeration for HVAC Technicians DVDS
– HVACR 201 (focus: refrigeration)
– Understanding Basic Electricity in the Real World DVDs
– Videos Refrigeration Piping
– Video: 24-hour Refrigeration
AHRI
Air Conditioning, Heating and Refrigeration Institute (2111 Wilson Boulevard,
Suite 510, Arlington, VA, 22201; tel: 703/524-8800; www.ari.org)
Standards and Guidelines
Standard 700-2004
Specification for Fluorocarbon Refrigerants
Standard 740-1998
Refrigerant Recovery/Recycling Equipment
Standard 810-2012
Performance Rating of Automatic Commercial Ice-Makers
Standard 820-2012
Performance Rating of Ice Storage Bins
Standard 1200-2013 Performance Rating of Commercial Refrigerated Display
Merchandisers and Storage Cabinets
Guideline K-2009
Containers for Recovered Fluorocarbon Refrigerants
Guideline N-2012
Assignment of Refrigerant Color Containers
Guideline Q-2010
Content Recovery and Proper Recycling of Refrigerant Cylinders
Guideline T-2013
Specifying the Thermal Performance of Cool Storage Equipment
Other
– ARI Product Certification directory/database:
ARI certification consists of
manufacturers who voluntarily participate in independent testing to ensure that their
product will perform according to published claims at specified controlled testing
conditions.
– Industry Recycling Guide (IRG-2), Handling and Reuse of Refrigerants in the US,
1994
ASHRAE
American Society of Heating, Refrigerating and Air-Conditioning Engineers (1791
Tullie Circle, NE, Atlanta, GA 30329; tel: 404/636-8400; www.ashrae.org)
Standards and Guidelines
Standard 15-2013
Safety Standard for Refrigeration Systems
Standard 34-2013
Designation and Safety Classification of Refrigerants
Other Documents
– ASHRAE Handbook – Refrigeration, 2014
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
APPENDIX B – BIBLIOGRAPHY & RESOURCES
PAGE 45
EPA
Environmental Protection Agency (6601 J; 1200 Pennsylvania Avenue, NW, Washington,
DC 20004, tel: 202/272-0167; www.epa,gov)
 §608, Clean Air Act, Stationary Refrigeration and Air-Conditioning, Halon Blends &
Handling
 Significant New Alternatives Policy (SNAP) program: www.epa.gov/ozone/snap
IAPMO
International Association of Plumbing and Mechanical Officials (4755 E.
Philadelphia Street, Ontario, CA, 91761; tel: 909/472-4100; www.iapmo.org)
– Uniform Mechanical Code, 2015
IIAR
International Association of Plumbing and Mechanical Officials (1001 N. Fairfax
Street, Suite 503, Alexandria, VA 22314; tel: 703/312-4200; www.iiar.org)
– ANSI/IIAR Standard 1-2012 American National Standard for Definitions and
Terminology Used in IIAR Standards
– ANSI/IIAR Standard 2-2008 American National Standard for Equipment, Design and
Installation of Closed-Circuit Ammonia Mechanical Refrigerating Systems
– ANSI/IIAR Standard 3-2012 American National Standard for Ammonia Refrigeration
Valves
– BSR/IIAR Standard 4-201X Installation of Closed-Circuit Ammonia Refrigerating
Systems
– ANSI/IIAR Standard 5-2013 Start-up and Commissioning of Closed-Circuit Ammonia
Refrigeration Systems
– BSR/IIAR Standard 6-201x Maintenance and Inspection of Closed-Circuit Ammonia
Refrigeration Systems
– ANSI/IIAR Standard 7-2013 Developing Operating Procedures for Closed-Circuit
Ammonia Mechanical Refrigerating Systems
– BSR/IIAR Standard 8-201x Decommissioning of Closed-Circuit Ammonia
Refrigerating Systems
Other
Process Safety Management & Risk Management Program Guidelines
Ammonia Refrigeration Library
Ammonia Data Book – 2nd Edition
Ammonia Refrigeration Management (ARM) Program
Ammonia Refrigeration Piping Handbook
The CO2 Handbook – 2014 Edition
Engineering Safety Relief Systems Guidebook
Industrial Refrigeration Energy Efficiency Guidebook
ICC
International Code Council (500 New Jersey Avenue, NW 6th Floor, Washington,
DC 20001; tel: 888/422-7233; www.iccsafe.org)
– International Mechanical Code, 2015
NATE
North American Technician Excellence (2111 Wilson Boulevard, Suite 510,
Arlington, VA, 22201; tel: 703/276-7247; www.natex.org)
NATE offers certifications tests for service and installation technicians to highlight
relevant applied knowledge. Separate ‘service’ and ‘installation’ tests are given in the
following specialty categories: Light Commercial Refrigeration (LC), and Commercial
Refrigeration (RC).
RSES
Refrigeration Service Engineers Society (1911 Rohlwing Road, Suite A, Rolling
Meadows, IL, 60008; tel: 847/297-6464; www.rses.org)
Various training manuals, self-study courses, classes and CDs to enhance the professional
development of practitioners within the refrigeration sector.
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
Page 46
UL
APPENDIX B – BIBLIOGRAPHY & RESOURCES
Underwriters Laboratories Inc., (333 Pfingsten Road, Northbrook, IL 60062; tel:
847/272-8800; www.ul.com)
Standards
UL 471
Standard for Commercial Refrigerators and Freezer
UL 984
Hermetic Refrigerant Motor-Compressors
ANSI/ACCA 14 QMref – 2015 (Commercial Refrigeration Maintenance)
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