Master-Bilt PRS-2 Refrigeration Systems Manual

Master-Bilt PRS-2 Refrigeration Systems Manual
Refrigeration
Systems
Installation
Manual
3/20 Rev. M 040086
Table
of
Contents
Tools Required
General Information
Unpacking & Inspection for Ceiling Mount
Unpacking & Inspection for Remote
General Installation Instructions
Ceiling Mount Refrigeration Systems
Remote Refrigeration Systems
Instructions for Pre-Charged Lines
Instructions for Wire Harness
Outdoor Systems
Membrane Roofing Material
Operation
Standard Temperature (Cooler) Systems
Low Temperature (Freezer) Systems
Maintenance
Maintenance Analysis
2
3
4-5
4
5
6-17
6-15
16-18
16-17
18
19-20
19
21-23
21
22-23
24
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3/20 Rev. M 040086
Tools Required
Tools
required for uncrating and installation of the
•
•
•
•
•
•
3
Refrigeration System
Safety Glasses
Pry Bar
Hammer
Adjustable Open End Wrench (2)
Drill Driver
Pencil
3/20 Rev. M 040086
Refrigeration Systems-General Information
CEILING MOUNTED REFRIGERATION SYSTEM
GENERAL INFORMATION
This Refrigeration System was produced utilizing the latest in manufacturing technology, the highest quality
materials available, along with innovations that make it a distinctive product in its field. Despite rigid controls in
the production of the product, there is no substitute for thoroughly reading and UNDERSTANDING the instructions
that follow. The result will be an orderly and efficient installation. Please take the time to follow the steps explicitly!
UNPACKING & INSPECTION--CEILING MOUNT SYSTEM
Check the Delivery Receipt for the number of pieces that made up the shipment and make sure that the number
of pallets, boxes or crates agrees with that number. Each piece should be clearly marked with the same five-digit
order number that appears on the Delivery Receipt as the shipper's number.
Examine the general condition of the shipment and, as soon as unpacking is completed, carefully inspect all parts
for possible shipping damage. If damaged parts are discovered, contact the supplier immediately.
It is recommended the condensing unit be elevated from the deck a minimum of 12"-18" to ensure the condenser
fan is not drawing or pulling heat reflected off the building roof or pavement in a grade level installation in which
the summer heat may exceed +120°F. Ambient temperature around the system should be less than +90°F and
50% RH.
Delivery Receipt
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Refrigeration Systems-General Information
UNPACKING & INSPECTION FOR REMOTE REFRIGERATION SYSTEMS
Check the Delivery Receipt for the number of pieces that made up the shipment and make sure that the number
of pallets, boxes or crates agrees with that number. Each piece should be clearly marked with the same five-digit
order number that appears on the Delivery Receipt as the shipper's number.
Examine the general condition of the shipment and, as soon as unpacking is completed, carefully inspect all parts
for possible shipping damage. If damaged parts are discovered, contact the supplier immediately.
For outdoor systems it is recommended the condensing unit be elevated from the deck a minimum of 12"-18" to
ensure the condenser fan is not drawing or pulling heat reflected off the building roof or pavement in a grade level
installation in which the summer heat may exceed +120°F.
For indoor systems the ambient temperature around the system should be less than +90°F and 50% RH.
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General Installation Instructions
GENERAL INSTALLATION INSTRUCTIONS
This section has the general instructions for installing the ceiling mounted Refrigeration System. Before proceeding,
also see the following section on mounting "Remote Systems with Electric Vaporizer", if applicable.
Note: Proper "temporary" support of the ceiling panel with the cut out must be added during the installation of the
refrigeration.
Note: Due to the weight of these systems (approximately 150 lbs.), it is highly recommended that proper lifting
equipment, such as a fork lift or material lift, be utilized during installation. Be sure to allow for sufficient airflow
around the condenser. A 4" minimum clearance is required above the condensing unit. If multiple units are located
in the same area, be sure they do not exhaust hot air into one another. Refer to section titled "Locating and
Mounting Condensing Units" for details. In addition to allowing for proper airflow, consideration should be given to
the final mounting location of the refrigeration system relative to the customer location to avoid any possible risk
of noise impacting the customer experience.
Position the insulated evaporator section of the Refrigeration System over the hole in the walk-in ceiling section.
Special care should be used when positioning the evaporator section over the ceiling cut-out. Be sure not to
damage the gasket underneath the evaporator section.
Seal perimeter as described in the Diffuser Installation Instructions found on pages 8 and 9. When reinstalling the
diffuser panel, make sure the ceiling section divider on the panel seals against the black gasket. Some adjustment
may be required by simply bending the ceiling section divider slightly forward or backward. This will prevent any
short cycling of discharge and return air.
Note: On smaller refrigeration systems, you may elect to install the system on the ceiling section while the section
is still on the floor. CAUTION! Make sure to fasten down the system to the ceiling panel. The ceiling section and
the refrigeration system may then be erected together in the normal sequence of assembly as shown in the Kold
Locker™ Walk-in Installation Instructions. This method is not practical and should not be used with larger systems
of 100 series or above.
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General Installation Instructions
GENERAL INSTALLATION INSTRUCTIONS
Some systems require a permanent connection to an electrical service and a connection at the junction box
located within the condensing unit housing. Refer to the serial tag for all pertinent electrical data. These systems
must be connected to a power supply disconnect switch and wired according to local and national electric codes.
With some models, no plumbing drain is required. For models requiring an optional condensate vaporizer (see
page 12 for installation details).
Wiring Instruction for The Two-Piece Refrigeration System
Note: Do not mount power disconnect to the condensing unit housing
After the equipment is properly located on the walk-in: Each piece of equipment is pre wired to a designated
termination in the J-box. Electrical power connections are provided and labeled appropriately. For a closecoupled system use the wiring harness provided to compete the final electrical connection between the
condensing unit sections directly to the evaporator section. Note the diagrams for electrical details.
This will require a single point power connection at the electrical J-box on the condensing unit base. Refer to
serial tag for electrical circuit requirements.
Remote Applications (Power Drop Situations)
Each piece of equipment is pre-wired to a designated termination in the J-box. Electrical power connections are
provided and labeled appropriately. Complete power connections in J-box electrical provided. See serial tag for
each component for electrical specifications.
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General Installation Instructions
PRS-2 SERIES DIFFUSER INSTALLATION INSTRUCTIONS
1. Remove diffuser from ceiling panel before installing ceiling panel (Figures 1 and 2)
Figure 2
Figure 1
2. Lift PRS-2 series into position on top of walk-in. Note: Do not slide PRS-2 series into position as cowl gasket
damage will occur. If the PRS-2 series must be slid into position, place PRS-2 series on a piece of cardboard
prior to moving to prevent gasket damage.
3. Inspect cowl gasket to ensure proper placement (Figure 3)
Figure 3
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3/20 Rev. M 040086
General Installation Instructions
4. Seal cowl to ceiling at gasket seam above diffuser panel using provided silicone (Figure 4)
Figure 4
5. Replace diffuser panel removed in step 1.
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General Installation Instructions
CONNECTING REFRIGERATION BASE TO THE EVAPORATOR
(INDOOR CLOSE-COUPLED MODELS)
Carefully align the condensing unit and evaporator section at the refrigeration connections using the alignment
bolts provided on the evaporator section. Position the condensing unit’s slots over the positioning bolts on the
evaporator section. Fasten the bolts securely to the evaporator section.
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General Installation Instructions
MAKING REFRIGERATION CONNECTION (CLOSE-COUPLED SYSTEMS)
By employing self-sealing refrigeration couplings, the condensing unit section, evaporator section, and the
connecting tubing are separately pre-charged with refrigerant and leak tested at the factory before shipment.
Carefully align the Condensing unit and evaporator section at the refrigeration connections using the alignment
bolts provided.
1. Remove the dust caps and plugs from the couplings and inspect them to see if the synthetic seals are intact.
2. Using a clean cloth, wipe the coupling seals and threaded surfaces to prevent the inclusion of any dirt or foreign
material in the system.
3. Lubricate the synthetic seal in the male half of the couplings with refrigeration oil and thread the two coupling
halves together BY HAND to ensure proper mating of the threads. Note: Make certain that the insulated suction
line is connected to the coupling half marked "Suction Line" and that the bare tube liquid line is connected to the
coupling half marked "Liquid Line".
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General Installation Instructions
OPTIONAL FEATURE - ELECTRIC CONDENSATE VAPORIZER
Indoor PRS-2 series Applications (do not use condensate vaporizer for an outdoor application)
The vaporizer is intended to be mounted in the orientation shown below. Note the location of the condensate drain
coming from the evaporator and locate the vaporizer so the condensate water will drain into it. Use the supplied
plastic tubing and copper elbow and extend the drain into the vaporizer. Cut the plastic tubing to the desired length.
Provide power to the electric vaporizer per local national electrical codes. Avoid locating vaporizer below any
electrical enclosures.
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General Installation Instructions
OPTIONAL FEATURE - ELECTRIC CONDENSATE VAPORIZER
PRS-2 series Applications using kit number 133141 (208/230 Volt Models Only)
Confirm the unit is disconnected from the power supply then remove housing from condensing unit. Route the
drain line from the evaporator section plastic tubing, copper elbow and clamps from kit as shown in Figure 1.
Remove hole plug from vaporizer and position so that copper tube extends into pan as shown in Figure 2. Make
sure the end of the copper elbow is pointing down and not up inside the vaporizing pan so it does not create a
trap. Remove hole plug and feed power supply cord through hole in control panel and connect leads at terminal
block posts and ground wire to ground stud per local and national electric codes as shown in Figure 3. Secure
cord with strain relief and use wire clamp as needed to locate cord. Replace condensing unit housing and
energize unit.
WARNING: THE VAPORIZER IS HOT AND THE COVER MUST BE USED!
Figure 1
Figure 2
Figure 3
Vaporizer electrical specification for 132962 and vaporizer electrical for 133141 vaporizer kit noted below.
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General Installation Instructions
FOR REMOTE SYSTEMS WITH ELECTRIC VAPORIZER
Set the Refrigeration System evaporator section over the
hole in the ceiling section. Align the evaporator with the clips
provided and lock in place. Refer to the Diffuser Installation
Instructions found on pages 8 and 9. Seal the seam using
silicone provided. When reinstalling the Diffuser Panel, make
sure that the ceiling section divider located on the panel
seals against the black gasket. Some adjustment may be
required by simply bending the ceiling section divider slightly
forward or backward. This will prevent any short cycling of
discharge and return air.
Fasten the evaporator section down to the ceiling using the
provided drive screws, which can be found taped to the side
of the insulated evaporator section.
CAUTION! This must be done to prevent the entire
refrigeration system from moving during operation.
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General Installation Instructions
LOCATING AND MOUNTING CONDENSING UNITS
Walls or Obstructions
The units should be located so that air may
circulate freely. For proper air flow, all sides of
the unit should be a minimum of the width of the
condensing unit away from any wall or obstruction. It is preferred that this distance be increased
whenever possible.
Building Wall
Condensing units (CU’s) must be located where there is an unrestricted supply of clean, fresh air. Do not locate
units where air discharge from one will enter into the air intake of others nor where the air flow is toward a wall or
obstruction. Avoid locating units in restricted spaces where heat will build up and can enter the condenser. There
must be room around the unit for regular inspection and service. Master-Bilt recommends 200CFM in any area
where condensing units may be located. Air flow should be sufficient to maintain an ambient temperature of no
more than 85°
Condensing Unit
Walk-in Ceiling
Multiple units
For units placed side by side, the minimum
distance between units should be the width of
the largest unit. If units are placed end to end,
the minimum distance between units should be 4
feet.
Condensing Unit
Condensing Unit
Walk-in Ceiling
Roof mounted condensing units must have adequate support for their operating weight. Corrosive atmospheres
require custom design condensers.
It is recommended the condensing unit be elevated from the deck a minimum of 12"-18" to ensure the condenser
fan is not drawing or pulling heat reflected off the building roof or pavement in a grade level installation in which
the summer heat may exceed +120°F
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Remote Refrigeration Systems
INSTRUCTIONS FOR PRE-CHARGED LINES - REMOTE SYSTEMS
By employing self-sealing refrigeration couplings, the condensing unit section, evaporator section, and the
connecting tubing are separately pre-charged with refrigerant and leak tested at the factory before shipment.
Follow steps 1-8 below to install the connecting tubing at both the condensing unit and the evaporator section.
1. Carefully uncoil the suction line. This is the line covered with a continuous
length of sponge rubber insulation.
2. Carefully uncoil the liquid line. The liquid line is the smaller diameter, bare
copper tube.
3. Before making any connections, determine the routing of both lines and
carefully hand bend them to suit the situation. Keep any bend radius rather
large to prevent kinking the tubing. It is a general practice to route the suction
and liquid line parallel and close together in the installation.
4. Remove the dust caps and plugs from the couplings and inspect them to
see if the synthetic seals are intact.
5. Using a clean cloth, wipe the coupling seals and threaded surfaces to
prevent the inclusion of any dirt or foreign material in the system.
6. LUBRICATE the synthetic seal in the male half of the couplings with
refrigeration oil and thread the two coupling halves together BY HAND to
ensure proper mating of the threads. Note: Make certain that the insulated
suction line is connected to the coupling half marked "Suction Line" and that
the bare tube liquid line is connected to the coupling half marked "Liquid Line".
Note: Always use two wrenches on the coupling body hex nut and on the union
to prevent twisting of the tube while tightening the connections as described in
the next step.
7. Using the proper size wrench on the union nut, tighten until the coupling
bodies bottom, or until a definite resistance is felt. Tighten an additional 1/6 to
1/4 turn. This final turn is needed to compress the spring loaded fitting allowing
the free flow of refrigerant and to seal the coupling. We advise leak checking
the couplings to ensure there are no leaks.
Note: legs shown in photos are not standard but instead, an optional item.
16
Connecting to the Condensing Unit Side
3/20 Rev. M 040086
Remote Refrigeration Systems
8. Once the suction line is connected, the sponge insulation must be pulled up to cover the quick connects. Tie
or tape off the insulation to prevent air infiltration and reduce water/ice formation on the suction line.
All valves are open and the system is ready for operation. Remember, the refrigeration couplings on this system
are self sealing and, if the need ever arises, the couplings may be disconnected without any loss of refrigerant.
IMPORTANT: Since this system is equipped with pre-charged refrigerant lines, it is the installing contractor’s
responsibility to ensure that the quick connect refrigerant couplings are properly mated and are leak free. It is also
their responsibility upon start-up to check the system for proper operation and make any necessary temperature
control or thermal expansion valve adjustments.
Note: A drain line is required to be run by the contractor for this type of installation.
CAUTION: Line set must not exceed 3 feet longer than required length to complete connection or improper oil
return may result in compressor failure. Contact the Service Department with model and serial number for further
assistance.This information is also included on a tag attached to the line set.
Some systems require a permanent connection to an electrical service and a connection at the junction
box located within the condensing unit housing. Refer to the serial tag for all pertinent electrical data.
These systems must be connected to a power supply disconnect switch and wired according to local and
national electric codes. Do not attach power disconnect to the condensing unit housing.
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Remote Refrigeration Systems
with
Wire Harness
1. All systems with a wire harness will have a “K” at or near the end of the model number.
Example: RCPB100DC-A-50K.
2. These systems will come with the wire harness already wired to the condensing unit section of the refrigeration
system.
3. These wire harnesses will have approved seal tight conduit and connectors.
4. Before power is connected to the condensing unit section it should first be wired to the evaporator section with
the wire harness provided.
5. Remove the control box cover on the evaporator section.
6. Make the proper connections inside the control box on the evaporator section as shown in the wiring diagram
provided with the system.
7. Replace the cover on the control box when wiring is completed.
8. Now power can be brought to the condensing unit section of the refrigeration system.
If you do not have the wiring diagram, contact the factory for the correct one. Have your model and serial
number available when you call.
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Outdoor Systems
OUTDOOR SYSTEMS UTILIZING A MEMBRANE ROOFING MATERIAL
Curb
1. After the walk-in is completely assembled,
place the curb face down on top of
the ceiling sections (curb is fastened
to crate base during shipping and
must be removed and installed prior to
membrance roof installation). To ensure
proper opening alignment, mark the
outside portion of the curb on the ceiling
sections with a marking pencil.
2. Remove the paper from the gasket and
position the curb, gasket side down, on
the pencil line. Press down firmly. Note:
Movement of the curb is very difficult
after the gasket adheres to the ceiling
section. Refer to Figure 1.
Alignment Marks
Ceiling Sections
Walk-In
Figure 1
Membrane
Roofing
Fasten to Edge
of Curb Frame
Opening
Cutout Line
Walk-In
Figure 2
19
3. Lay the membrane roofing material
over the walk-in ceiling sections and
curb leaving a six inch overhang
on all four sides of the walk-in.
Using an utility knife, cut a hole in
the membrane roof approximately
1-1/2” in from the edge of the
opening. (The resulting hole in the
membrane will be smaller than the
ceiling opening). Fold the 1-1/2”
membrane flaps into the opening,
notching the membrane around
the locators and divider. Use either
sheet metal screws, caulk, glue,
etc. to fasten the membrane roofing
material to the inside edge of the
curb frame. Refer to Figure 2. Do
not make any penetrations in the top
of the membrane roof. Any needed
penetrations should be through the
side wall to maintain the integrity of
the roof.
3/20 Rev. M 040086
Outdoor Systems
4. Set the Refrigeration System over
the opening in the curb. Refer to the
Diffuser Installation Instructions found
on pages 8-9. Seal the seam as
described in the instructions. When
reinstalling the Diffuser Panel, make
sure that the ceiling section divider
located on the panel seals against the
black gasket. Some adjustment may
be required by simply bending the
ceiling section divider slightly forward
or backward. This will prevent any
short cycling of discharge and return
air.
Capsule Pak™
Membrane
Roofing
Opening
Before proceeding to step 5, pull
membrane straight and smooth before
installing the trim.
Walk-In
Note: Seal gasket at top of curb with
silicone.
Figure 3
5. Fold all four corners of the membrane
roofing material over the walk-in corners as shown in Figure 4.
6. Attach the trim and door hood (if your walk-in is equipped with them)
by using the provided pan head sheet metal screws. Ensure the trim
and membrane roof material cover the joint between the ceiling and
wall panels. Refer to figure 5. Note: The trim may have to be cut to fit.
7. Trim off all excess membrane roofing material
from under the trim with a utility knife. Do not allow the knife to cut the
metal panel, as this will damage the coating and cause rust.
Fold Membrane
Figure 4
Trim by Nor-Lake
Membrane Roof
Material
Ceiling Panel
NOTE: In outdoor installations, the condensate
line should be plumbed to the nearest drain
and a P-trap installed near the end. Check local
building codes. Outside drain lines must also
be wrapped with a suitable heater wire and
insulated if they are ever subjected to below
freezing temperatures.
3"
Figure 5
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3/20 Rev. M 040086
Operation
OPERATION
STANDARD TEMPERATURE (COOLER) SYSTEMS
Each PRS-2 system is equipped with a highly efficient electronic controller that regulates an electronic expansion
valve in response to evaporator superheat and return air temperature, featuring demand defrost fan control
technology. This system will operate differently from previous system you may have worked with in the past. Refer
to the controller instructions located in the condensing unit for additional information.
Important: It is the installing contractor’s responsibility to check the operation upon start-up and make necessary
temperature adjustments as required for proper operation.
Note: PRS-2 series Refrigeration Systems that are designed for outdoor installation will be fitted with electric
crankcase heaters, electrically heated condensate drain tubes and automatic head pressure control valve.
Refrigeration Controller
PRS-2 series refrigeration systems may be equipped with an electronic programmable temperature control or an
advanced, electronic control system. See separate instructions on the operation of the electronic temperature
control.
Defrost Cycle (Cooler System)
One of two different controls are utilized. The first is a Dixell control which is a digital thermostat that uses a
conventional style defrost system. The controller stops the condensing unit. During this time, the evaporator fans
continue to run, blowing +35-38˚F air over the fins. This process will warm the evaporator above +32˚F. After 15
minutes, the condensing unit should restart.
The other control method is the electronic controller which uses an automatic on-demand defrost algorithm
that eliminates unnecessary defrosts typically associated with time-based alternatives which reduces energy
consumption.
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Operation
LOW TEMPERATURE (FREEZER) SYSTEMS
The low temperature, automatic electric defrost PRS-2 series refrigeration system utilizes one of two different
controls. First, a Dixell control which is digital thermostat that uses a programmable set point and a differential for
the refrigeration cycle. Second is the electronic controller with a programmable set point and a preset algorithm to
cycle the fans and compressor in order to maintain a tighter room temperature.
Important: It is the installing contractor’s responsibility to check the operation upon start-up and make necessary
temperature control adjustments as required for proper operation.
Note: PRS-2 series Refrigeration Systems that are designed for outdoor installation will be fitted with electric
crankcase heaters, electrically heated condensate drain tubes, automatic head pressure control valve, and the
"pump-down cycle".
Defrost Cycle
There are two types of defrost cycles. The first is in the Dixell control. This process uses a conventional style
defrost system. This controller stops the condensing unit every 6 hours. The display will read DEF. The evaporator
fans will turn off and the electric heaters will turn on.
The other is the electronic controller which uses an automatic or demand defrost algorithm that eliminates
unnecessary defrosts typically associated with time based alternatives which reduces energy consumption. For
additional information see the controller instructions located in the condensing unit section of the refrigeration
system.
Defrost Cycle Termination
The Dixell control will heat the evaporator coil to 50°F or 36 minutes whichever comes first.
The electronic controller will run the coil heater until the coil is above 32°F. At this point it will work very different than
a traditional defrost cycle. The heaters will pulse on and off allowing the heat to radiate through the coil until both
coil sensing probes reach 50°F or 40 minutes whichever happens first. The fan(s) in the evaporator housing will not
start, however, until the fan delay cycle has expired. See the "Fan Delay" below.
Fan Delay
When a defrost cycle is terminated the evaporator fan(s) will not start until the evaporator coil temperature is
reduced to about +20°F. Once this temperature is reached, the fan delay cycle will turn the fans back on continuing
the refrigeration cycle.
The fan delay feature is an important part of defrosting. If the fan(s) was permitted to start immediately following
a defrost period, the heat that accumulated in the evaporator housing would be circulated throughout the walk-in,
raising the temperature considerably. In addition, any droplets of moisture that remained clinging to the fins of the
evaporator coil would be blown into the storage space. The fan delay feature provides for a short refrigeration cycle
WITHOUT the evaporator fan(s) to prevent these conditions.
Note: During the initial startup of a PRS-2 series Refrigeration System on warm walk-in, the evaporator fan(s) will
not start until the evaporator coil reaches +20°F. Further, the evaporator fans may cycle "on" and "off" several times
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Operation
until the evaporator coil reaches and maintains +20°F.
Drain Tube Heater
Low temperature ceiling mounted PRS-2 series Refrigeration Systems may employ a low wattage, electric heater
strip. This heater is spirally wound around the condensate drain tube that extends from the drain pan below the
evaporator coil to the evaporator section housing wall. This heater is energized ccontinually to allow the free flow
of the condensate water to the outside of the evaporator section. The discharged water should then be removed
per local code. The heater and drain tube are covered with an insulated tape.
NOTE:
Indoor application: If the condensate vaporizer is not used the condensate line should be plumbed to the nearest
drain and a P-trap installed near the end. Check local building codes.
Outdoor application: Drain lines must have a P-trap installed at the termination point and be wrapped continuously
with a suitable heater wire and insulated if they are ever subjected to below freezing temperatures.
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Maintenance
MAINTENANCE
WARNING: When servicing any PRS-2 series Refrigeration System or performing any maintenance
procedure, always disconnect the main power supply.
The condensing unit is accessible by removing the condensing unit housing. The evaporator coil section is
accessible by unlatching and removing the evaporator section housing cover. For access to the fan blade(s) and
for oiling the fan motor on some models, remove the louver on the walk-in ceiling.
Cleaning the Condenser and Evaporator Coils
The efficiency of the refrigeration system, to a great extent, depends upon the unrestricted f.flow of air through the
condenser and evaporator coils. For this reason both coils should be as clean as possible at all times and should
have an unrestricted supply of air.
Cleaning the condenser should be done at a minimum of every 3 months.
A vacuum cleaner with a bristle attachment can be used to clean the coil. If debris on the coil cannot be removed
easily, a bristle brush can be used to loosen it by gently brushing in the same direction as the fins so as not
to damage them and restrict air flow. An air compressor can be used to clean the condenser coil also. The air
flow should be directed through the coil from the fan motor side. A damp hand towel can be blocked against the
opposite side so that the majority of the dust will be captured in the towel minimizing the mess in the room.
NOTE: Do not use corrosive cleaners as they may damage the copper tubing or welds.
Hot Gas Vaporizer Pan
Condensate from the evaporator pan is discharged into a hot gas vaporizer pan, which is located in the condensing
unit housing. Here the hot discharge gas from the compressor elevates the temperature of the water and it
vaporizes into the atmosphere. This pan should be cleaned periodically to remove solids that remain after the
moisture is evaporated. Do not scrub the copper tubing very hard or use corrosive cleaners as this may
damage the copper lines or welds.
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Maintenance Analysis
MALFUNCTION
POSSIBLE CAUSE
SOLUTION
Compressor will not start no hum
1.
2.
3.
4.
5.
Unplugged or power off
Fuse blown or removed
Overload tripped
Control stuck open
Wiring incorrect
1.
2.
3.
4.
5.
Plug in service cord or turn power on
Replace fuse
Determine reasons and correct
Repair or replace
Check wiring against the diagram
Compressor will not start hums but trips on overload
protector
1.
2.
3.
4.
Improperly wired
Low voltage to unit
Starting capacitor defective
Relay failing to close
1.
2.
3.
4.
Check wiring against the diagram
Determine reason and correct
Determine reason and replace
Determine reason, correct or replace
Compressor starts and runs,
1. Low voltage to unit
1. Determine reason and correct
but short cycles on overload
2. Overload defective
2. Check current, replace overload protector
protector
3. Excessive head pressure
3. Check ventilation or restriction in refrigeration system
4. Compressor hot — warm ambient
4. Check refrigerant charge, fix leak if conditions necessary
Compressor operates long
or continuously
1. Short of refrigerant
2. Control contact stuck
3. Evaporator coil iced
4. Restriction in refrigeration system
5. Dirty condenser —warm ambient
conditions
6. Warm ambient
1.
2.
3.
4.
5.
Fix leak, add charge
Repair or replace
Determine cause, defrost manually
Determine location and remove restriction
Clean condenser
6.
Address ambient conditions
Compressor runs fine, but
short cycles
1.
2.
3.
4.
5.
Overload protector
Cold control
Overcharge
Air in system
Undercharge
1.
2.
3.
4.
5.
Check wiring diagram
Differential too close - widen
Reduce charge
Purge and recharge
Fix leak, add refrigerant
Starting capacitor open,
shorted or blown
1.
2.
3.
Relay contacts stuck
Low voltage to unit
Improper relay
1.
2.
3.
Clean contacts or replace relay
Determine reason and correct
Replace
Relay defective or burned out
1.
2.
Incorrect relay
Voltage too high or too low
1.
2.
Check and replace
Determine reason and correct
Refrigerated space too warm
1.
2.
3.
4.
5.
6.
7.
Control setting too high
1.
Refrigerant overcharge
2.
Dirty condenser
3.
Evaporator coil iced
4.
Not operating
5.
Air flow to condenser or
6.
evaporator blocked
Warm ambient conditions
7.
Reset control
Purge refrigerant
Clean condenser
Determine reason and defrost
Determine reason, replace if necessary
Remove obstruction for free air flow — no storage
on top of walk-in
Ambient conditions should be 90° or less
Standard temperature system
freezes the product
Control setting is too low
Control points stuck
Reset the control
Replace the control
1.
2.
1.
2.
Objectionable noise
1. Fan blade hitting fan shroud
1.
2. Tubing rattle
2.
3. Vibrating fan blade
3.
4. Condenser fan motor rattles
4.
5. General vibration
5.
6. Worn fan motor bearings
6.
Reform or cut away small section of shroud
Locate and reform
Replace fan blade
Check motor bracket mounting, tighten
Compressor suspension bolts not loosened
on applicable models - loosen them
Replace fan motor
Water overflowing from
1. Air leak between refrigeration system
1.
evaporator drain pan or
and walk-in panel. condensate vaporizer pan
2. Drain line from evaporator drain
2.
pan to condensate vaporizer is
blocked with foreign material.
3. Drain line from evaporator drain
3.
pan to condensate vaporizer is
blocked with ice.
4. Walk-in operating in high humidity
4.
environment (heavy door usage).
Check that refrigeration system is properly set
in panel opening.
Clean blockage from inside of drain line.
25
Check that drain line heater (on freezers)
is working and repair or replace as required.
Plumb drain line from evaporator to floor
drain or replace high gas vaporizer with
electric vaporizer. Consult factory for further information.
3/20 Rev. M 040086
26
3/20 Rev. M 040086
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