Crown Boiler | TWZ200 | Specifications | Crown Boiler TWZ200 Specifications

D
E S I G N E D
T O
L
E A D
TWZ Series
Oil-Fired Hot Water Boilers
Installation Instructions
These instructions must be affixed on or adjacent to the boiler
Models:
• TWZ065
• TWZ075
• TWZ100
• TWZ090
• TWZ125
• TWZ150
• TWZ120
• TWZ175
• TWZ200
Warning: Improper installation, adjustment, alteration,
service or maintenance can
cause property damage, injury,
or loss of life. For assistance or
additional information, consult a
qualified installer, service agency
or the oil supplier. Read these
instructions carefully before
installing.
Manufacturer of Hydronic Heating Products
P.O. Box 14818 3633 I. Street
Philadelphia, PA 19134
www.crownboiler.com
WARNINGS FOR THE HOMEOWNER
FOLLOW ALL INSTRUCTIONS and warnings
printed in this manual and posted on the boiler.
unless alarms or other safeguards are in place to
prevent such damage
INSPECT THE BOILER, BURNER AND
CONTROLS ANNUALLY. To keep your boiler safe
and efficient, have a service technician follow the
Service checklist near the end of this manual.
DO NOT BLOCK AIR FLOW into or around the
boiler. Insufficient air may cause the boiler to
produce carbon monoxide or start a fire.
KEEP FLAMMABLE LIQUIDS AWAY from the
boiler, including paint, solvents, and gasoline.
The boiler may ignite the vapors from the liquids
causing explosion or fire.
IF YOU ARE NOT QUALIFIED to install or service
boilers, do not install or service this one.
THE BOILER MAY LEAK WATER at the end of
its useful life. Be sure to protect walls, carpets,
and valuables from water that could leak from the
boiler.
KEEP CHILDREN AND PETS away from hot
surfaces of the boiler, boiler piping, and vent pipe.
CARBON MONOXIDE (CO) is an odorless, deadly
gas that may be introduced into your home by
any malfunctioning fuel-burning product or vent
system failure. Consider installing CO alarms near
bedrooms in all levels of the building to warn you
and your family of potential CO exposure.
PROTECT YOUR HOME IN FREEZING
WEATHER. A power outage, safety lockout, or
component failure will prevent your boiler from
lighting. In winter, your pipes may freeze and
cause extensive property damage. Do not leave
the heating system unattended during cold weather
WARNINGS FOR THE INSTALLER
READ THIS ENTIRE MANUAL before attempting
installation, start-up, or service. Improper
installation, adjustment, alteration, service, or
maintenance may cause serious property damage,
personal injury, or death.
INSTALL ALL GUARDS, cover plates, and
enclosures before operating the boiler.
SIZE THE BOILER PROPERLY relative to the
design heat load or, if using domestic hot water
priority, the peak hot water load, whichever
is larger. A grossly oversized boiler will cycle
excessively and this will lead to premature failure
of the boiler and its components. Our warranty
does not apply to damage from excessive cycling.
DO NOT DISCONNECT PIPE FITTINGS on the
boiler or in the heating system without first verifying
that the system is cool and free of pressure and
that your clothing will protect you from a release
of hot water or steam. Do not rely solely on the
boiler’s temperature and pressure gage when
making this judgment.
ADHERE TO ALL LOCAL CODE
REQUIREMENTS. Contact your local code
inspector prior to installation. In the absence of
a local code, adhere to the latest editions of the
Installation of Oil Burning Equipment ANSI/NFPA
31 in the USA or CAN/CSA B139, Installation Code
for Oil Burning Equipment in Canada.
USE PROPER PERSONAL PROTECTION
EQUIPMENT when servicing or working near the
boiler. Materials of construction, flue products, and
fuel contain alumina, silica, heavy metals, carbon
monoxide, nitrogen oxides, and/or other toxic or
harmful substances that can are hazardous to
health and life and that are known to the State of
California to cause cancer, birth defects, and other
reproductive harm.
ALL WIRING must comply with the National
Electrical Code ANSI/NFPA 70 (in the USA) or the
Canadian Electrical Code CSA C22.1 (in Canada)
and any local regulations.
1
Table of Contents
I.
Product Description ...............................................................................3
II.
Specifications .........................................................................................3
III. Before Installing ....................................................................................4
IV.
V.
Locating the Boiler ................................................................................5
Air for Combustion & Ventilation .........................................................7
VI. Venting ...................................................................................................11
VII. System Piping ........................................................................................13
VIII. Tankless Heater Piping ..........................................................................17
IX.
Fuel Line Piping .................................................................................... 18
X.
Wiring ....................................................................................................21
XI.
Start-Up & Checkout .............................................................................26
XII. Operation ...............................................................................................29
XIII. Service & Maintenance ..........................................................................36
XIV. Troubleshooting .....................................................................................39
XV. Parts .......................................................................................................42
2
I Product Description
The TWZ series boiler is a cast iron oil-fired water boiler designed for use in closed forced circulation heating systems.
This boiler must be vented by natural draft into a lined masonry or metal chimney, or Type L vent. An adequate supply of
air for combustion, ventilation and dilution of flue gases must be available in the boiler room. An optional tankless heater is
available to generate domestic hot water.
II Specifications
FIGURE 2.0: GENERAL CONFIGURATION *
TABLE 2.1: GENERAL SPECIFICATIONS
Boiler Model
TWZ065
TWZ075
TWZ100
TWZ090
TWZ125
TWZ150
TWZ120
TWZ175
TWZ200
Number of
Sections
3
3
3
4
4
4
5
5
5
Burner
Input
(Gal/hr)
0.65
0.75
1.00
0.90
1.25
1.50
1.20
1.75
2.00
DOE Heating
Capacity
(Btu/hr)
80000
91000
120000
111000
152000
179000
147000
212000
241000
Approx.
I=B=R Net
Water
Rating (Btu/hr) AFUE (%) Content (Gal)
70000
86.1
16.0
79000
85.8
16.0
104000
84.3
16.0
97000
86.0
20.0
132000
85.1
20.0
156000
84.0
20.0
128000
86.0
24.0
184000
85.1
24.0
210000
84.7
24.0
3
Dimensions (inches)
"A"
"B"
"C"
17-3/8
8 5/16
6
17-3/8
8 5/16
6
17-3/8
8 5/16
6
22-3/8
10 13/16
7
22-3/8
10 13/16
7
22-3/8
10 13/16
7
27-3/8
13 5/16
8
27-3/8
13 5/16
8
27-3/8
13 5/16
8
TABLE 2.2: OPTIONAL TANKLESS HEATER RATINGS
Boiler Model
TWZ065
TWZ075
TWZ100
TWZ090
TWZ125
TWZ150
TWZ120
TWZ175
TWZ200
Tankless Heater Rating
(Gal/min)
2.75
3.00
3.25
3.25
3.75
4.00
3.50
4.25
4.75
Notes:
1. Net Ratings are based on piping and pick-up allowances of 1.15.
2. Burner Capacity Rating, GPH is based on #2 oil with a Gross
Heating Value equal to 140000 BTU/Gal.
3. Maximum Working Pressure, Water - 50 PSI.
4.
Tankless Heater Ratings based on I=W=H test standard.
III Before Installing
1) Safe, reliable operation of this boiler depends upon installation by a professional heating contractor in strict accordance
with this manual and the requirements of the authority having jurisdiction.
• In the absence of an authority having jurisdiction, installation must be in accordance with this manual and the latest
edition of Installation of Oil Burning Equipment (ANSI/NFPA31).
• Where required by the authority having jurisdiction, this installation must conform to the latest edition of Standard for
Controls and Safety Devices for Automatically Fired Boilers (ANSI/ASME CSD-1).
2) Make sure that a properly sized chimney is available which is in good condition. Consult the authority having
jurisdiction, Part VI of this manual, andANSI/NFPA31 for additional information on venting requirements.
Power (“Side Wall”) Venting - Important Note
Two problems arise when any oil-fired appliance is power vented:
1. There is sometimes an accelerated rate of soot buildup on the oil burner cad-cell, spinner etc.
2. There is a potential for severe damage to the side of the structure in the event that the boiler operates at a high smoke
level. This can happen for many reasons, some of which are out of the control of both the installer and appliance
manufacturer.
Crown Boiler Company recommends the use of a chimney to vent the TWZ series boilers. If a power venter must be used, it
is the responsibility of the installer and power vent manufacturer to “engineer” the power vent system. CROWN BOILER
COMPANY WILL ASSUME NO RESPONSIBILITY FOR DAMAGE TO SIDING, ETC. FROM A POWER
VENTED OIL-FIRED BOILER. THIS APPLIES REGARDLESS OF THE CAUSE OF THE SOOTING.
3) Make sure that the boiler is correctly sized:
• For heating systems employing convection radiation (baseboard or radiators) use an industry accepted
•
•
•
sizing method such as the I=B=R Guide RHH published by the Air-Conditioning, Heating and Refrigeration Institute (AHRI).
For new radiant heating systems refer to the radiant tubing manufacturer’s boiler sizing guidelines.
For systems including a Crown Mega-Stor indirect water heater, size the boiler to have either the Heating
Capacity required for the Mega-Stor or the I=B=R Net Rating required for the heating system, whichever results in the larger boiler.
For systems that incorporate other indirect water heaters, refer to the indirect water heater manufacturer’s
instructions for boiler output requirements.
4) In some cases, boilers installed at altitudes above 2000ft may require a different burner configuration from that at sea
level. Consult the local Crown representative for more information.
4
IV Locating the Boiler
WARNING
FAILURE TO OBSERVE THE FOLLOWING LOCATION REQUIREMENTS COULD RESULT
IN PROPERTY DAMAGE, A FIRE, EXPLOSION OR CARBON MONOXIDE (CO) HAZARD.
1) Clearances:
• Observe the minimum clearances shown below. Except as noted, these clearances apply to all combustible construction, as well as noncombustible walls, ceilings and doors. Also see Figure 4.0.
Front – 24”
Left Side – 6”
Right Side – 6”
Rear – 6”
Top – 6”
Single Wall Chimney Connector (to combustible construction) - 18”
• A 24” service clearance from the jacket is recommended from the top of the boiler. This clearance may be
reduced to that shown above; however, servicing the boiler will become increasingly difficult as this clearance
is reduced.
2) If listed Type L vent is used, follow vent pipe manufacturer recommendations for minimum clearances.
3) Do not install this boiler directly on a combustible surface. Where it is desired to install the TWZ over a non-carpeted
combustible surface, install the boiler on the base shown in Figure 4.1.
4) Do not install this boiler in a location where gasoline or other flammable vapors or liquids will be stored or used. Do not
install this boiler in an area where large amounts of airborne dust will be present, such as a workshop.
`
FIGURE 4.0: CLEARANCES
5
FIGURE 4.1: installation over a combustible floor
6
V Air for Combustion and Ventilation
WARNING
•
INSUFFICIENT COMBUSTION AIR SUPPLY MAY RESULT IN THE PRODUCTION AND RELEASE OF SOOT OR DEADLY CARBON MONOXIDE (CO) INTO THE HOME WHICH CAN CAUSE PROPERTY DAMAGE, SEVERE PERSONAL INJURY OR DEATH.
•
THIS BOILER IS NOT DESIGNED FOR USE IN A SPACE THAT IS DEPRESSURIZED RELATIVE TO THE OUTDOORS. OPERATING THIS BOILER IN A DEPRESSURIZED SPACE MAY CAUSE PROPERTY DAMAGE, SEVERE PERSONAL INJURY OR DEATH.
Sufficient fresh air must be supplied for combustion and ventilation. Provisions for combustion and ventilation air for oil
burning equipment must be made in accordance with Section 1.5, Air for Combustion and Ventilation, in the latest edition of
Installation of Oil Burning Equipment (ANSI/NFPA 31).
To ensure an adequate supply of air for combustion, ventilation and flue gas dilution, start by determining whether the
boiler is to be installed in a building of unusually tight construction. A building of unusually tight construction can be defined
as one having the following features:
• Walls and ceilings exposed to outside atmosphere have a continuous water vapor retarder with a rating of 1 perm or
less with openings gasketed and sealed
• Weather stripping has been added on openable windows and doors
• Caulking and sealants are applied to areas such as joints around window and door frames, between sole plates and
floors, between wall-ceiling joints, between wall panels, at penetrations for plumbing, electrical, and gas lines, and
at other openings.
For Buildings of Other than Unusually Tight Construction
1) Determine whether the boiler is to be installed in a confined space - A confined space is defined as having a volume less
than 50 cubic feet per 1000 BTU/hr input of all appliances installed in that space. To determine whether the boiler room is a
confined space:
a. Total the input of all appliances in the boiler room in thousands of BTU/hr. Round the result to the next highest
1000 BTU/hr.
b. Find the volume of the room in cubic feet. The volume of the room in cubic feet is:
Length (ft) x width (ft) x ceiling height (ft)
In calculating the volume of the boiler room, consider the volume of adjoining spaces only if no doors are installed
between them. If doors are installed between the boiler room and an adjoining space, do not consider the volume of
the adjoining space, even if the door is normally left open.
c. Divide the volume of the boiler room by the input in thousands of BTU/hr. If the result is less than 50, the boiler
room is a confined space.
Example:
A TWZ090 and a water heater are to be installed in a room measuring 6 ft - 3 in x 7 ft with an 8 ft ceiling. The
water heater has an input of 30000 BTU/hr:
Input of TWZ090 = 0.90 Gal/hr x 140000 BTU/Gal = 126000 BTU/hr
Total input in thousands of BTU/hr = (126000 BTU/hr + 30000 BTU/hr)/1000 = 156
Volume of room = 6.25 ft x 7 ft x 8 ft = 350 ft3
350/156 = 2.24. Since 2.24 is less than 50, the boiler room is a confined space.
7
FIGURE 5.0: BOILER INSTALLED IN CONFINED SPACE, ALL AIR FROM INSIDE
2) Unconfined Space - Natural infiltration into the boiler room will normally provide adequate air for combustion and ventilation without additional louvers or openings into boiler room.
3) Confined Space - Provide two openings into the boiler room, one near the floor and one near the ceiling. The top edge of
the upper opening must be within 12” of the ceiling and the bottom edge of the lower opening must be within 12” of the floor
(Figure 5.0).
• Each opening must have a free area of 1 square inch per 1000 BTU/hr input of all fuel burning appliances in the boiler
room. The minimum opening dimension is 3 inches. Minimum opening free area is 100 square inches per opening.
• If the total volume of both the boiler room and the room to which the openings connect is less than 50 cubic feet per
1000 BTU/hr of total appliance input, install a pair of identical openings into a third room. Connect additional rooms
with openings until the total volume of all rooms is at least 50 cubic feet per 1000 BTU/hr of input.
• The “free area” of an opening takes into account the blocking effect of mesh, grills, and louvers. Where screens are
used, they must be no finer than ¼” (4 x 4) mesh.
For Buildings of Unusually Tight Construction:
1) Openings must be installed between the boiler room and the outdoors or a ventilated space, such as an attic or crawl
space, which communicates directly with the outdoors.
2) Two openings are required. The top edge of the upper opening must be within 12 inches of the ceiling. The bottom
edge of the lower opening must be within 12 inches of the floor.
3) Size openings and ducts as follows:
• Vertical ducts or openings directly outdoors (Figure 5.1, Figure 5.2, and Figure 5.3) ‑ Each opening must have
a free cross sectional area of 1 square inch per 4000 BTU/hr of the total input of all fuel fired appliances in the
boiler room but not less than 100 square inches. Minimum opening size is 3 inches.
• Openings to outdoors via horizontal ducts (Figure 5.4) ‑ Each opening must have a free cross sectional area of 1
square inch per 2000 BTU/hr of the total input of all fuel fired appliances in the boiler room but not less than 100
square inches. Minimum opening size is 3 inches.
• The “free area” of an opening takes into account the blocking effect of mesh, grills, and louvers. Where screens
are used, they must be no finer than ¼” (4 x 4) mesh.
8
FIGURE 5.1: ALL AIR FROM OUTDOORS, VENTILATED CRAWL SPACE AND ATTIC
FIGURE 5.2: ALL AIR FROM OUTDOORS, VIA VENTILATED ATTIC
9
FIGURE 5.3: ALL AIR FROM OUTDOORS, USING OPENINGS INTO BOILER ROOM
FIGURE 5.4: ALL AIR FROM OUTDOORS, USING HORIZONTAL DUCTS INTO BOILER ROOM
10
VI Venting
WARNING
•
IMPROPER VENTING MAY RESULT IN PROPERTY DAMAGE AND/OR THE RELEASE OF FLUE GASES, WHICH CONTAIN DEADLY CARBON MONOXIDE (CO), INTO THE HOME, WHICH CAN CAUSE SEVERE PERSONAL INJURY OR DEATH.
•
INSPECT EXISTING CHIMNEY BEFORE INSTALLING BOILER. FAILURE TO CLEAN OR REPLACE DAMAGED PIPE OR TILE LINING WILL CAUSE PROPERTY DAMAGE, SEVERE PERSONAL INJURY OR DEATH.
Vent installation must be in accordance with local building codes, or the local authority having jurisdiction.
Typical vent installation is illustrated by Figure 6.0. The components of vent installation are the vent connector (breeching),
barometric draft regulator, and chimney.
FIGURE 6.0: TYPICAL VENT SYSTEM INSTALLATION AND COMPONENTS
1) Acceptable Chimneys - The following chimneys may be used to vent a TWZ series boiler:
• Listed Type L vent - Install in accordance with the manufacturer’s instructions, the terms of its listing, and applicable
codes.
• Masonry Chimney - The masonry chimney must be constructed in accordance with the latest edition of Standard
for Chimneys, Fireplaces, Vents, and Solid Fuel Burning Appliances (NFPA 211) and lined with a clay liner or other
listed lining system. Do not vent a TWZ series boiler into an unlined chimney.
11
2) Acceptable Vent Connectors - The following may be used for vent connectors:
• Listed Type L vent.
• Single Wall Galvanized Pipe - Use 0.018” (26 gauge) or heavier.
3) Chimney and Vent Connector Sizing - See Table 6.1 for minimum vent connector and chimney sizing. The vent
connector size must not be smaller than boiler flue collar diameter.
4) Do not vent this appliance into any portion of a mechanical vent system operating under positive pressure.
5) Do not connect the boiler into a chimney flue serving an open fireplace or other solid fuel appliance.
6) Prior to boiler installation, inspect chimney for obstructions or other defects and correct as required. Clean chimney as
necessary.
7) Vent pipe should slope upward from boiler not less than one inch in four feet. No portion of vent pipe should run
downward or have sags. Vent pipe must be securely supported.
8) The vertical section of vent pipe coming off the boiler should be as tall as possible, while still maintaining the proper
clearance from the horizontal vent connector to combustibles and the proper pitch called for in (7) above.
9) Vent pipe should be installed above the bottom of the chimney to prevent blockage.
10) Vent pipe must be inserted flush with inside face of the chimney liner and the space between vent pipe and chimney
sealed tight. A thimble permanently cemented in place can be used to facilitate removal of chimney connector for cleaning.
11) Install the barometric draft regulator in accordance with the regulator manufacturer’s instructions.
12) Secure all joints in the vent connector system with sheet metal screws. This includes the joint between the vent
connector and the boiler collar, as well as the barometric draft regulator. Use at least three screws at each joint.
TABLE 6.1: MINIMUM RECOMMENDED BREECHING AND CHIMNEY SIZE
Boiler
Min Breeching
Model
Dia. (inches)
TWZ065
6
TWZ075
6
TWZ100
6
TWZ090
7
TWZ125
7
TWZ150
7
TWZ120
8
TWZ175
8
TWZ200
8
Min. Recommended Chimney Size and Height
Round I.D. (in) Rectangular I.D. (in)
Height (ft)
6
8x8
15
6
8x8
15
6
8x8
15
7
8x8
15
7
8x8
15
7
8x8
15
8
8x8
15
8
8x8
15
8
8x8
15
Power (“Side Wall”) Venting - Important Note
Two problems arise when any oil-fired appliance is power vented:
1. There is sometimes an accelerated rate of soot buildup on the oil burner cad-cell, spinner etc.
2. There is a potential for severe damage to the side of the structure in the event that the boiler operates at a high smoke
level. This can happen for many reasons, some of which are out of the control of both the installer and appliance
manufacturer.
Crown Boiler Company recommends the use of a chimney to vent the TWZ series boilers. If a power venter must be used, it
is the responsibility of the installer and power vent manufacturer to “engineer” the power vent system. CROWN BOILER
COMPANY WILL ASSUME NO RESPONSIBILITY FOR DAMAGE TO SIDING, ETC. FROM A POWER
VENTED OIL-FIRED BOILER. THIS APPLIES REGARDLESS OF THE CAUSE OF THE SOOTING.
12
VII System Piping
WARNING
• INSTALL BOILER SO THAT THE ELECTRICAL COMPONENTS ARE PROTECTED
FROM WATER (DRIPPING, SPRAYING, RAIN, ETC.) DURING APPLIANCE
OPERATION AND SERVICE (CIRCULATOR REPLACEMENT, ETC.).
• OPERATION OF THIS BOILER WITH CONTINUOUS RETURN TEMPERATURES
BELOW 120°F CAN CAUSE SEVERE HEAT EXCHANGER CORROSION DAMAGE.
• OPERATION OF THIS BOILER IN A SYSTEM HAVING SIGNIFICANT AMOUNTS OF
DISSOLVED OXYGEN CAN CAUSE SEVERE HEAT EXCHANGER CORROSION
DAMAGE.
• DO NOT USE TOXIC ADDITIVES, SUCH AS AUTOMOTIVE ANTIFREEZE, IN A
HYDRONIC SYSTEM.
• PIPE RELIEF VALVE DISCHARGE TO A SAFE LOCATION. THE RELIEF VALVE
MAY DISCHARGE SCALDING HOT WATER.
• DO NOT INSTALL A VALVE IN THE RELIEF VALVE DISCHARGE LINE.
• DO NOT MOVE RELIEF VALVE FROM FACTORY LOCATION.
• DO NOT PLUG RELIEF VALVE DISCHARGE. BLOCKING THE RELIEF VALVE MAY
RESULT IN BOILER EXPLOSION.
Standard Piping
Figure 7.1 shows typical boiler system connections on a single zone system. Additional information on hydronic system
design may be found in the I=B=R Guide RHH published by the Air-Conditioning, Heating and Refrigeration Institute
(AHRI). The components in this system and their purposes are as follows:
FIGURE 7.1: STANDARD BOILER PIPING
13
1) Relief valve (Required) - Mount the relief valve on the top left side of the boiler as shown in Figure 7.1 using the 3/4”
nipple provided. The relief valve shipped with the boiler is set to open at 30 psi. This valve may be replaced with one
having a pressure up to the “Maximum Allowable Working Pressure” shown on the rating plate. If the valve is replaced,
the replacement must have a relief capacity in excess of the DOE heating capacity for the boiler.
Pipe the discharge of the relief valve to a location where water or steam will not create a hazard or cause property damage
if the valve opens. The end of the discharge pipe must terminate in an unthreaded pipe. If the relief valve discharge is not
piped to a drain, it must terminate at least 6 inches above the floor. Do not run relief valve discharge piping through an
area that is prone to freezing. The termination of the relief valve discharge piping must be in an area where it is not likely
to become plugged by debris.
2) Circulator (Required) - Figure 7.1 shows the ideal location of the circulator which is in the supply piping immediately
downstream of the expansion tank. A less ideal, but acceptable, location for most residential circulators is in the return (if
this is done, be sure that adequate clearance exists to open the door.
3) Expansion Tank (Required) - If this boiler is replacing an existing boiler with no other changes in the system, the
old expansion tank can generally be reused. If the expansion tank must be replaced, consult the expansion tank
manufacturer’s literature for proper sizing.
4) Fill Valve (Required) - Either a manual or automatic fill valve may be used. The ideal location for the fill is at the
expansion tank.
5) Automatic Air Vent (Required) - At least one automatic air vent is required. Manual vents will usually be required in
other parts of the system to remove air during initial fill.
6) Low Water Cut-Off (Required in some situations) - A low water cut-off is required when the boiler is installed above
radiation. In addition, some codes such as ASME CSD-1, require low water cut-offs. Codes may also require that this
low water cut-off have a manual reset function. The low water cut-off may be a float type or probe type, but must be
designed for use in a hot-water system. The low water cut-off should be piped into the boiler supply just above the boiler
with no intervening valves between it and the boiler.
Use a low water cut-off that breaks the 120 VAC supply to the boiler. Do not attempt to wire a 24-volt low water cut-off
into the boiler factory wiring.
7) Manual Reset High Limit (Required by some codes) - This control is required by ASME CSD-1 and some other codes.
Install the high limit in the boiler supply piping just beyond the boiler with no intervening valves. Set the manual reset
high limit as far above the operating limit setting as possible, but not over 240°F. Wire the control to break the 120 VAC
electrical supply to the boiler.
8) Flow Control Valve (Required under some conditions) - The flow control valve prevents flow through the system unless
the circulator is operating. A flow control valve may be necessary on converted gravity systems to prevent gravity
circulation. Flow control valves are also used to prevent “ghost flows” in circulator zone systems through zones that are
not calling for heat.
9) Isolation Valves (Optional) - Isolation valves are useful if the boiler must be drained, as they will eliminate having to drain
and refill the entire system.
10) Drain Valve - The drain valve is shipped in the boiler parts bag. Install it in the tee on the boiler return as shown in
Figure 1.
IMPORTANT
The 1 1/2” Plugged Tapping On The Bottom Rear Section Is Present
For Manufacturing Purposes Only. Do Not Attempt To Use This
Tapping As A Return Connection.
14
FIGURE 7.2: INDIRECT WATER HEATER BOILER SIDE PIPING
FIGURE 7.3: BOILER BYPASS PIPING
Piping for Special Situations
Certain types of heating systems have additional requirements. Some of the more common variations follow:
1) Indirect Water Heaters - Figure 7.2 shows typical indirect water heater piping. Boiler piping is the same as for any twozone system. Figure 7.2 shows circulator zoning, which is usually preferred for indirect water heaters. Size the circulator
and indirect water heater piping to obtain the boiler water flow through the indirect water heater called for by the indirect
water heater manufacturer.
2) Large Water Volume Systems - The piping shown in Figure 7.3 will minimize the amount of time that the boiler operates
with return temperatures below 120°F on these systems. A bypass is installed as shown to divert some supply water
directly into the return water. The bypass pipe should be the same size as the supply. The two throttling valves shown are
adjusted so that the return temperature rises above 120°F during the first few minutes of operation. A three-way valve can
be substituted for the two throttling valves shown.
15
3) Low Temperature Systems - Some systems, such as radiant tubing systems, require the system water temperature to
be limited to a value below the temperature of the water leaving the TWZ. These systems also typically have return
temperatures well below the 120°F minimum.
Figure 7.4 illustrates the use of a heat exchanger to connect the TWZ boiler to this type of system. The heat exchanger
will permit the transfer of heat from the boiler water to the low temperature system while holding the system supply and
boiler return temperatures within their limits. For this system to work properly, the heat exchanger must be properly sized
and the correct flow rates are required on either side of the heat exchanger. Consult the heat exchanger manufacturer for
sizing information. The water in the boiler is completely isolated from the water in the system. This means that separate
fill and expansion tanks are required for the heating system loop.
There are several other ways to connect low temperature systems to the non-condensing boilers like the TWZ such as four
way mixing valves and variable speed injection pumping systems.
4) Systems containing oxygen - Many hydronic systems contain enough dissolved oxygen to cause severe corrosion damage
to a cast iron boiler such as the TWZ. Some examples include:
• Radiant systems that employ tubing without an oxygen barrier.
• Systems with routine additions of fresh water.
• Systems which are open to the atmosphere.
If the boiler is to be used in such a system, it must be separated from the oxygenated water being heated with a heat
exchanger as shown in Figure 7.4.
Consult the heat exchanger manufacturer for proper heat exchanger sizing as well as flow and temperature requirements.
All components on the oxygenated side of the heat exchanger, such as the pump and expansion tank, must be designed for
use in oxygenated water.
5) Air Handlers - Where the boiler is connected to air handlers through which refrigerated air passes, use flow control valves
in the boiler piping or other automatic means to prevent gravity circulation during the cooling cycle.
FIGURE 7.4: ISOLATION OF BOILER FROM SYSTEM WITH A HEAT EXCHANGER
16
VIII Tankless Heater Piping
If the TWZ is installed with an optional tankless heater, pipe the heater as shown in Figure 8.1. The components in this
system and their functions are as follows:
1) Mixing Valve (Required) - During the heating season, the water exiting the tankless heater may be 180 degrees or more.
The mixing valve blends hot water leaving the tankless heater with cold water so as to maintain the hot water supplied
to the fixtures at a fixed temperature. This saves energy, increases the amount of usable hot water available to the
homeowner, and reduces the risk of scalding.
Install a mixing valve with a setting range of approximately 110 to 130F. Follow the manufacturer’s instructions for
installing this valve. Usually a “heat trap” will be required between the coil and the “hot” connection on the mixing valve.
WARNING
A MIXING VALVE DOES NOT ELIMINATE THE RISK OF SCALDING.
• SET THE MIXING VALVE AND BOILER LOW LIMIT ADJUSTMENTS AS LOW AS POSSIBLE.
• FEEL WATER BEFORE SHOWERING OR BATHING.
• If anti-scald or anti-chill protection is required, use devices specifically designed for such service. Install and maintain these devices in accordance with the manufacturer’s
instructions. Do not use the mixing valve as a substitute for pressure balancing valves or other devices required by plumbing codes to protect against scalding.
2) Flow Restrictor (Recommended) - If water is drawn from the tankless coil at a rate in excess of the rating in Table 2.2,
the temperature of the hot water may be too low to be of use. The use of a flow restrictor will prevent this problem by
limiting the rate at which water can pass through the tankless heater. If a restrictor is used, select one having a rating
in GPM approximately equal to the rating shown in Table 2.2. If possible, locate this restrictor at least 3 feet from the
tankless heater inlet so that it is not subjected to excessive temperatures when no water is flowing through the coil.
3) Pressure Relief Valve (Required) - Limits the pressure in the tankless heater and piping. Use an ASME constructed valve
designed for domestic water service, such as the Watts #3L. Note that this is a pressure relief valve, not a T&P valve.
Select a valve with a pressure setting less than or equal to the working pressure marked on the tankless coil. Pipe the
discharge to a safe location using piping the same size as the discharge connection on the valve.
4) Hose Bib Valves (Recommended) - These valves permit the coil to be periodically “backflushed” to remove sediment.
5) Globe or Ball Valve (Recommended) - Used to adjust the flow through the entire tankless heater system if needed.
6) Unions (Required) - Tankless heaters may require periodic gasket replacement or other maintenance which requires
removal of the heater from the boiler. Install unions anywhere in the tankless heater piping that will facilitate removal of
the heater.
17
FIGURE 8.1: TANKLESS HEATER PIPING
IX Fuel Line Piping
WARNING
• UNDER NO CIRCUMSTANCES CAN COPPER WITH SWEAT STYLE CONNECTORS
BE USED.
• DO NOT USE COMPRESSION FITTINGS.
• OIL PIPING MUST BE ABSOLUTELY AIRTIGHT OR LEAKS OR LOSS OF PRIME
MAY RESULT.
• SOME JURISDICTIONS REQUIRE THE USE OF A FUSIBLE SHUTOFF VALVE AT
THE TANK AND/OR THE BURNER. IN ADDITION, SOME JURISDICTIONS REQUIRE
THE USE OF A FUSIBLE ELECTRICAL INTERLOCK WITH THE BURNER CIRCUIT.
CHECK YOUR LOCAL CODES FOR SPECIAL REQUIREMENTS.
Fuel line piping design, materials and construction must be in accordance with local building codes, requirements of the local authority having jurisdiction, and, the latest edition of the Standard for the Installation of Oil-Burning Equipment (ANSI/
NFPA 31) in the United States and CSA B139-04 for installation in Canada. Refer also to the instruction manuals provided
with the burner and oil pump.
18
FIGURE 9.1: ONE-PIPE GRAVITY SYSTEM
Depending on the location of the fuel oil storage tank in relation to an oil burner, there are four types of oil piping systems
generally being used:
a) ONE-PIPE GRAVITY SYSTEM - used when a fuel oil storage tank is positioned above an oil burner fuel pump. See
Figure 9.1. A vertical distance from top of the tank to center line of the pump (Dimension ‘H’) over 8 feet will result in
a pump inlet pressure in excess of the 3-psi limit in NFPA-31.
b) ONE-PIPE LIFT SYSTEM (not recommended) - Used when a fuel oil storage tank is located below an oil burner fuel
pump. See Figure 9.2. The vertical distance from bottom of the tank to center line of the pump (Dimension ‘H’) must
not exceed that shown in the pump manufacturer’s instructions. Although all oil piping systems must be airtight, onepipe lift systems are particularly susceptible to nuisance lockout problems if the suction line is not completely airtight.
A two-pipe lift system is therefore recommended over a one-pipe lift system.
c) TWO-PIPE GRAVITY SYSTEM (not recommended) - Used when a fuel oil storage tank is located above an oil
burner fuel pump. See Figure 9.3. A vertical distance from top of the tank to center line of the pump (Dimension ‘H’)
over 8 feet will result in a pump inlet pressure in excess of the 3-psi limit in NFPA-31. This type of system should be
converted to a one-pipe gravity system, as doing so will result in lower inlet line flow and longer filter life.
d) TWO-PIPE LIFT SYSTEM - used when a fuel oil storage tank is located below an oil burner fuel pump suction port.
See Figure 9.4. The vertical distance from bottom of the tank to center line of the pump (Dimension ‘H’) must not
exceed that shown in the pump manufacturer’s instructions. Distance ‘H’ allowed is reduced by the number of fittings,
filters and valves installed in the line.
Once the type of system has been selected, observe the following:
1) Fuel line piping must be airtight. Do not use compression type fittings for tubing connections in fuel line piping. Use
only listed flare type fittings. Cast iron threaded fittings shall not be used.
2) Piping shall be substantially supported and protected against physical damage and corrosion where required.
3) Refer to supplied oil pump instruction manual for proper connections. On one-pipe systems, ensure that the fuel pump
return port plug is tightened securely.
4) Some fuel pumps, such as the Suntec A and B series, are supplied with a loose bypass plug which must be installed on
two-pipe systems. If such a plug is supplied, install it as shown in the pump manufacturer’s instructions. Do not install this
bypass plug on one-pipe systems as pump seal damage will result.
5) Do not use check valves, especially on gravity feed systems.
6) Do not use Teflon tape for threaded connections. Use a listed non-hardening thread sealant instead.
19
7) Attach required piping between burner fuel pump and fuel oil storage tank. Install one fuel shut-off valve near the storage
tank and second fuel shut-off valve near the oil burner fuel pump. Use heavy wall copper tubing in a continuous run. On
two-pipe systems, the return line should terminate 3” - 4” above suction line depth within the storage tank. Refer to the
pump manufacturer’s instructions for tube sizing information.
8) All systems require an oil filter. On TWZ065 and TWZ075 boilers, the use of a Garber cartridge type filter is
recommended.
9) Use only #2 Fuel Oil with physical and chemical characteristics meeting the requirements of ASTM D-396.
FIGURE 9.2: ONE-PIPE LIFT SYSTEM
FIGURE 9.3: TWO-PIPE GRAVITY FEED SYSTEM
20
FIGURE 9.4: TWO-PIPE LIFT SYSTEM
X Wiring
WARNING
• All wiring and grounding must be done in accordance with the authority having jurisdiction
or, in the absence of such requirements, with the National Electrical Code (ANSI/NFPA
70).
• Disconnect electrical power to the boiler and heating system before servicing. Positively
assure that no voltage is present. Lock electrical boxes to prevent someone from
inadvertently restoring power before the heating system is safe to operate.
• Never defeat or jump out safety devices.
• Protect each boiler circuit with a properly sized over-current protection device.
• Make electrical connections carefully according to the boiler’s wiring diagram and
instructions.
• Wire additional field supplied safety limits, such as low water cutoffs and temperature limit
devices, in series with the 120V circuit used to power the boiler. Do not alter the boiler’s
factory wiring when adding an additional limit device.
1) 120 Volt Wiring - The boiler should be provided with its own 15A branch circuit with fused disconnect. 120VAC power connections are made inside the L7248L cold start control or the L7224A warm start control as follows (also see Figures. 10.0
thru 10.2):
•
•
•
Hot (“black”) - Terminal “L1”
Neutral (“white”) - Terminal “L2”
Ground (“green” or bare) - Ground screw on case of L7248L or L7224A.
21
The heating circulator is either factory wired to the L7248L or L7224A circulator connections or the boiler is provided with a
flexible conduit “whip” that is factory wired to the L7248L or L7224A circulator connections. If the circulator is not already
wired to the control, connect it as follows:
• Circulator “Hot” - Black wire lead from “whip”
• Circulator “Neutral” - White wire lead from “whip”
•
2) Low Voltage Connections – Low voltage field connections are located as shown in Figure 10.0 and 10.1 and are as follows:
•
T-T - Connect to a 24 volt heating thermostat or other “dry contacts” (such as a zone panel end switch) that close upon
a call for heat. Follow thermostat manufacturer’s instructions. To insure proper thermostat operation, avoid installation
in areas of poor air circulation, hot spots (near any heat source or in direct sunlight), cold spots (outside walls, walls
adjacent to unheated areas, locations subject to drafts). Provide Class II circuit between thermostat (or zone controls) and
boiler.
•
1,2,3 - Used to connect EnviraCom thermostat, or other EnviraCOM device, approved by Crown for use with this boiler
(refer to instructions provided with EnviraCOM device).
3) Adding a Second Circulator Zone - The control provided on TWZ boilers can be used to control a second heating or DHW
circulator zone. If this is done, make the following 120VAC connections in addition to those described above (also see Figures 10.0 or 10.1):
•
•
Connect a 120VAC heating or DHW thermostat for the second zone between L1 and ZR.
Connect the DHW circulator or the second heating zone circulator between ZC and L2.
See Part XII of this manual for information on configuring the control to respond properly to the DHW or second heating
zone circulator. This information differs depending on the whether the boiler is equipped with the L7248L cold start control
used on boilers less tankless heater or the L7224A warm start control used on boilers with tankless heater.
4) Low Water Cut-offs - A properly installed low water cut-off (LWCO) prevents burner operation in the event that there is
insufficient water in the boiler. Many jurisdictions require the installation of a LWCO, as does NFPA-31. Install the LWCO
in the supply piping immediately above the boiler with no intervening valves. If a probe type LWCO is used, observe the
LWCO manufacturer’s required clearances around the probe. Use a LWCO that is wired so as to interrupt 120volt power to
the boiler in the event of a low water condition.
Crown 120V FWZ/TWZ LWCO Kit #411000 includes the LWCO, fittings, and wiring needed to meet the above
requirements.
CAUTION
• When making low voltage connections, make sure that no external power source
is present in the thermostat circuits. If such a power source is present, it could
destroy the boiler’s control. One example of an external power source that could
be inadvertently connected to the low voltage connections is a transformer in old
thermostat wiring.
• Do not attempt to use EnviraCOM connections for any purpose not explicitly permitted
by Crown Boiler Company. Attempting to do so may result in unreliable operation and/
or damage to controls.
• Do not use the transformer provided on the boiler to power external devices such as
zone valves. Doing so may cause damage to the transformer.
22
FIGURE 10.0: CONNECTIONS DIAGRAM, BOILERS LESS TANKLESS HEATER, COLD START CONTROL
23
FIGURE 10.1: CONNECTIONS DIAGRAM, BOILERS WITH TANKLESS HEATER, WARM START CONTROL
24
Riello 530SE:
Beckett 7505:
Carlin 40200:
FIGURE 10.2: CONNECTIONS DIAGRAM FOR BURNER PRIMARY CONTROLS
25
XI Start-up and Checkout
Use the following procedure for initial start-up of the boiler:
WARNING
• Never attempt to fill a hot empty boiler.
• Make sure that the area around the boiler is clear and free from combustible materials,
gasoline, and other flammable vapors and liquids.
• Safe reliable operation of this boiler requires that the burner be checked and adjusted by a
qualified oil serviceman using combustion test instruments.
• Failure to perform all of the checks outlined in the following procedure could result in
unreliable operation, damage to the boiler not covered under warranty, property damage,
or unsafe operation.
• All boilers equipped with burner swing door have a potential hazard which can cause
severe property damage, personal injury or loss of life if ignored. Before opening swing
door, turn off service switch to boiler to prevent accidental firing of burner outside the
combustion chamber. Be sure to tighten swing door fastener completely when service
is completed. In addition, the burner power cord will have to be disconnected from the
receptacle in the front jacket.
1) Ensure that the boiler and entire heating system are filled with water.
2) Check all new piping for leaks and purge heating system piping sections that are air bound.
3) Verify that the vent system is complete and free of obstructions prior to start-up of the boiler.
4) Inspect all wiring for loose or uninsulated connections, proper size fuses installed, etc.
5) Verify that oil tank is filled with #2 fuel oil meeting ASTM D396 specifications, oil piping has been tested and is air tight,
and shutoff valve(s) are closed.
6) Check initial settings of oil burner air band and air shutter, head setting etc., and readjust if needed. See Table 11.0 for
setup and combustion data pertaining to a particular boiler/ burner combination.
7) Attach plastic hose to oil pump vent fitting and provide a container to catch oil during oil pump bleeding procedure.
8) Install 0-200 PSI pressure gauge into oil pump gauge port.
9) Open all oil line shutoff valves.
10) Open flame observation port cover on burner swing door to see flame.
11) Adjust system thermostat to highest setting.
12) Set boiler controls (high limit, low limit, etc.) to suit individual requirements of the installation.
13) Turn the line service switch to “ON” position.
14) Crack open vent fitting on the oil pump and allow burner to run until a solid oil stream, free of air bubbles, flows for 15
seconds into container. As the vent fitting is closed, the burner should fire and flame should be visible through observation
port immediately (or after prepurge timing has expired, if a burner is so equipped). Refer to burner instructions for more
details.
15) Immediately upon firing the boiler, check the smoke level. If the smoke level is in excess of a #1, open the air adjustment
to bring the smoke level below a #1.
16) Make sure that the oil pressure matches that shown in Table 11.0 for the burner supplied. Adjust pressure if required.
17) Check the vacuum at the inlet of the fuel pump. Make sure that the vacuum does not exceed the fuel pump manufacturer’s
limit (consult the pump manufacturer’s instructions).
18) Close the flame observation cover.
19) After chimney has warmed-up to operating temperature, adjust barometric draft regulator for a draft of -0.02 inch w. c.
over the fire.
26
20) Check the CO2 and confirm that it is between the minimum and maximum limits shown in Table 11.0. Adjust if
necessary.
21) Verify that the smoke level still does not exceed #1 and that the draft over fire is -0.02 inch w.c.
22) Turn off the burner and remove pressure gauge. Install and tighten gauge port plug, then restart the burner.
23) Check for clean cutoff of the burner. Air in the oil line between fuel pump and nozzle will compress, while burner is
running, and expand, when burner shuts off, causing oil line pressure to drop and nozzle drip after burner stops. Cycle burner
on and off 5 to 10 times to purge air completely.
24) Check thermostat operation by raising or lowering its set point as required, cycling burner on and off.
25) Verify primary control operation and safety features according to procedure outlined in the instructions furnished with
control.
26) Check high limit control operation. Jump thermostat terminals and allow burner to run until boiler water temperature
exceeds high limit setting. The burner should shut down, and circulator continue running. Allow the temperature to drop
below the control setting. The burner must restart. Boiler installation is not complete unless these checks are made and are
satisfactory. Remove thermostat jumper and reconnect thermostat upon check completion.
27) After the boiler has operated for approximately 30 minutes, check the boiler and heating system for leaks. Repair any
leaks found at once.
After the above checks have been completed, leave thermostat(s) at desired setting. Leave all instructions provided with the
boiler with owner or in boiler room, displayed near boiler.
WARNING
ATTEMPTS TO USE BURNERS OR BURNER CONFIGURATIONS OTHER THAN
THOSE SHOWN IN TABLE 3 COULD RESULT IN RELIABILITY PROBLEMS,
PROPERTY DAMAGE OR UNSAFE OPERATION.
TABLE 11.0a: BECKETT BURNER CONFIGURATION AND SETUP DATA
BOILER MODEL
TWZ065
BURNER MODEL
AIR TUBE COMBO.
HEAD TYPE
STATIC PLATE
LOW FIRING RATE
BAFFLE
INSERTION LENGTH
PITCH ANGLE
STANDARD
NOZZLE
ALTERNATE
NOZZLE
PUMP PRESS (psi)
HEAD SETTING
STARTING:
SHUTTER SETTING
BAND SETTING
DRAFT OVER FIRE
(in w.c.)
MAX. SMOKE
(bacharach scale)
FLUE CO2 (%)
MIN.
MAX
AFG
70MMAQ
L1
3 3/8
BECKETT
#3708
2 1/4
2
HAGO
0.55/60B
DEL.
0.55/60W
140
NA
TWZ075
TWZ100
TWZ090
TWZ125
TWZ150
TWZ120
TWZ175
TWZ200
AFG
AFG
AFG
AFG
70MMAQ 70MMAQ 70MMAQ 70MDAQ
L1
L1
L1
V1
3 3/8
3 3/8
3 3/8
2 3/4
BECKETT
NONE
NONE
NONE
#3708
2 1/4
2 1/4
2 1/4
2 1/4
2
2
2
2
HAGO
HAGO
DEL.
HAGO
0.65/60B 0.85/60B 0.75/60B 1.00/60B
DEL.
DEL.
HAGO
DEL.
0.65/60W 0.85/60W 0.75/60B 1.00/60B
140
140
140
140
NA
NA
NA
0
AFG
70MDAQ
V1
2 3/4
AFG
70MLAQ
V1
NONE
AFG
70MLAQ
V1
NONE
AFG
70MLAQ
V1
NONE
NONE
NONE
NONE
NONE
2 1/4
2
HAGO
1.25/60B
DEL.
1.25/60B
140
0
2 1/4
2
HAGO
0.90/60B
DEL.
0.90/60B
175
0
2 1/4
2
HAGO
1.35/45B
DEL.
1.35/45B
175
3
2 1/4
2
HAGO
1.50/45B
DEL.
1.50/45B
175
4
1
1
10
2
5
2
7
0
10
0.5
10
6
8
1
6
6
8
4
-0.02
-0.02
-0.02
-0.02
-0.02
-0.02
-0.02
-0.02
-0.02
#1
#1
#1
#1
#1
#1
#1
#1
#1
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
27
TABLE 11.0b: CARLIN BURNER CONFIGURATION AND SETUP DATA
BOILER MODEL
BURNER MODEL
STANDARD
NOZZLE
PUMP PRESS (psi)
HEAD BAR
STARTING
BAND SETTING
DRAFT OVER FIRE
(in w.c.)
MAX. SMOKE
(bacharach scale)
FLUE CO2 (%)
MIN.
MAX
TWZ065
TWZ075
TWZ100
TWZ090
TWZ125
TWZ150
TWZ120
TWZ175
EZ-1HP
EZ-1HP
EZ-1HP
DEL.
HAGO
HAGO
0.55/70B 0.60/60ES 0.85/60B
150
150
150
0.50
0.60-0.65 0.85-1.00
EZ-1HP
DEL.
0.75/60A
150
0.75
EZ-1HP
EZ-1HP
EZ-1HP
DEL.
HAGO
HAGO
1.00/60A 1.25/60B 1.00/60B
150
150
150
0.85-1.00 1.10-1.25 0.85-1.00
EZ-2HP
DEL.
1.50/60A
150
1.50
0.90
1.75
-0.02
-0.02
-0.02
#1
#1
#1
#1
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
TWZ125
TWZ150
TWZ120
TWZ175
0.55
0.60
0.75
0.75
1.00-1.10 1.25-1.35
-0.02
-0.02
-0.02
-0.02
-0.02
#1
#1
#1
#1
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
TWZ200
TABLE 11.0c: RIELLO BURNER CONFIGURATION AND SETUP DATA
BOILER MODEL
BURNER MODEL
STANDARD
NOZZLE
PUMP PRESS (psi)
TURBULATOR
AIR
SHUTTER SETTING
DRAFT OVER FIRE
(in w.c.)
MAX. SMOKE
(bacharach scale)
FLUE CO2 (%)
MIN.
MAX
TWZ065
TWZ075
TWZ100
TWZ090
40F5
DEL
0.60/60A
150
0
40F5
DEL
0.85/60W
150
2
40F5
DEL.
1.00/60A
150
4
40F10
DEL
1.25/60B
150
1
2.60
2.85
4
3
3
3.8
-0.02
-0.02
-0.02
-0.02
-0.02
-0.02
#1
#1
#1
#1
#1
#1
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
11.0
12.5
28
40F10
HAGO
1.35/45B
150
1.5
TWZ200
40F10
DEL
1.65/45B
150
2
XII Operation
A. General Information
This boiler uses a proprietary version of the Honeywell L7248L Aquastat® cold start control used on boilers less tankless heater
or the L7224A Aquastat® warm start control used on boilers with tankless heater. to regulate water temperature and to manage
demands for up to two circulator zones.
Crown offers a low water cut-off kit that may be used with this control (PN 411000). Specific information on this kit, along with
installation and operating instructions, are available through Crown distributors and at www.crownboiler.com.
In accordance with the 2007 Energy and Independence Security Act, the L7248L cold start control first attempts to use residual
heat in the boiler to satisfy a space heating demand before firing the burner. In this manual, this function is referred to as a
“thermal purge”. For additional information see Part C of this section.
The L7224A warm start control is capable of thermal purge but it must be set by the installer. Note that using the thermal purge
on a warm start control may adversely affect the domestic hot water temperature in the tankless coil.
B. Reading Status and Using Menu
The boiler’s status, as well as all parameters, are viewed and adjusted using the 3 digit LED and three buttons shown in Figure
12.0. The L7248L and L7224A have four basic modes of operation (also see Figure 12.1):
1. Status Mode - This is the default mode of operation for the control. In it, the display alternates between StA and a number indicating the current status of the boiler. A list and description of these status numbers is shown in Table 12.2.
2. Operating Mode - Provides additional information about the current status of the boiler. Operating mode is entered by
pressing the I button shown in Figure 12.0. When this button is first pressed in Status mode, the display will alternately
display bt and the current boiler water temperature as shown in Figure 12.3. Pressing the I button again will display the next
line item shown in Table 12.2. In the same manner it is possible to advance through all of the “parameters” shown in Table
12.2. To return to Status mode, press I repeatedly until StA once again appears on the display. Alternatively, the control will
return to Status mode if no key is touched for 1 minute.
3. Error Mode - In Error mode, the control alternately displays Err and an error code. A list of these error codes is found on the
inside of the control cover, as well as in Section XIV of this manual (along with suggested corrective actions).
4. Adjustment Mode - Used to change parameters, such as high limit setting. See Part C for using Adjustment Mode.
FIGURE 12.0 LOCATION/APPEARANCE OF LED, BUTTONS
29
FIGURE 12.1: BOILER CONTROL MENU
STATUS MODE:
=Current Status (Table 12.2)
Press I to enter OPERATING MODE
Press and Hold I, ↑, and ↓ for at least 3 sec to
enter ADJUSTMENT MODE
= Current Boiler Temp.
= High Limit Setting
= Current Set Point
 = High Limit Differential
Cold Start Control Only
= High Limit Setting
= Low Limit Setting
Warm Start Control Only
 = Limit Differential
 = Low Limit Differential
Warm Start Control Only
= Low Limit Setting
Warm Start Control Only
=Use of 2 Zone
nd
=Circulator Overrun
 = Low Limit Differential
Warm Start Control Only
=Thermal Purge Time
=Call for Heat? (On/Off)
=Thermal Purge Temp
=Call for DHW? (On/Off)
=DHW Priority (ON/OFF)
=Temperature Units
N
Error Detected by
Aquastat®?
Lockout?
=Return to Status Mode
Y
Press I
Y
ERROR MODE
(Visible when Lockout is Present)
 = Code for Error Present (Table 14.0)


Except as shown above, press I to navigate through menu.
Use ↑,↓ to change parameters in Adjustment Mode
30
Press ↑ or ↓
Error Detected by
®
Aquastat ?
N
Status #
TABLE 12.2: STATUS CODES
Meaning
Description
1
Standby
8
Burner Demand
No call for heat or DHW
OR
Call for heat present , but boiler is in thermal purge (See PP on page 11)
OR
Call for heat/DHW present but boiler temperature is above set point (SP) setting.
The burner is running
OR
The burner is off due to an open limit (such as an external high limit or LWCO)
OR
The burner is being prevented from firing by its primary control.
Self test
17
Boiler was just energized and control is running a self check.
1 sec.

1 sec. 
1 sec.

FIGURE 12.3: TYPICAL OPERATING MODE DISPLAY (BOILER TEMP SHOWN)
NOTE
In operating mode, holding either the ↑ or ↓ button while viewing a given parameter will keep
the display on the actual reading. For example, pressing ↑ while reading boiler temperature as
shown in Figure 12.3 will keep the display on 180 for as long as this button is held. This makes
it easier to view readings “live” if they are changing rapidly
Parameter #
bt
SP
HL
HdF
LL
LdF
hr
dh
TABLE 12.4: OPERATING MODE PARAMETERS
Description
Meaning
Boiler Temperature
Current boiler water temperature measured by the control’s sensor.
Boiler Water Set Point
Current target temperature (always the same as the high limit setting)
Boiler will stop firing if boiler water temperature exceeds this value (Circulator/s
will continue to operate)
If high limit setting is reached, boiler water temperature will need to drop by this
High Limit Differential
amount before boiler will again fire during the same call for heat.
If the boiler water temperature falls below this point less the differential the
Low Limit Set Point
circulator is forced off and the burner is turned on. If the boiler water tempera(Warm Strat Control)
ture rises above this point the burner is turned off and the circulator is enabled to
respond to a call for heat.
This is the number of degrees the boiler water temperature must decrease below
Low Limit Differential
the Low Limit Set Point before the burner is turned on and the water flow
(Warm Start Control)
through the boiler is turned off.
High Limit Set Point
Heat Request Status
Shown as either ON or OFF. Indicates whether there is a call for heat.
DHW Request Status
Shown as either ON or OFF. Indicates whether there is a demand from the ZR
terminal for domestic hot water (DHW). Note that if the dh zone on the L7248L
or the L7224A is used as a second heating zone (see Table 12.5), this parameter
will be shown as OFF and hr will be shown as ON when a demand from ZR is
present.
31
TABLE 12.5a: ADJUSTMENT MODE PARAMETERS FOR L7248L - COLD START CONTROL
Factory
Status # Description
Setting
Permissible Range
High Limit Set Point
180F
140-240F
HL
High Limit Differential
15F
10-30F
HdF
ZC
ZC and ZR Terminal Function
dh
dh (DHW)
OR
Zr (2nd Heating Zone)
OR
ELL (“External Low Limit” NOT RECOMMENDED)
Or
PP
Circulator Overrun
0 min
0-10 minutes
Thermal Purge Time
2 min
2-20 minutes
St
Thermal Purge Start Temp
140F
140-180F
Pt
DHW Priority
ON
ON or OFF
F-C
Temperature Units
F
F or C
bAc
Exit Adjustment Mode
N/A
N/A
TABLE 12.5b: ADJUSTMENT MODE PARAMETERS FOR L7224A - WARM START CONTROL
Factory
Status # Description
Setting
Permissible Range
High Limit Set Point
180F
140-240F
HL
Low Limit Set Point
110F
110-220F
LL
Low Limit Differential
10F
10-25F
LdF
ZC
ZC and ZR Terminal Function
Zr
Zr (Zone Request, Call for
Heat)
OR
dh (DHW or 2nd Heating
Zone if Pt is set to OFF)
Or
PP
Circulator Overrun
0 min
0-10 minutes
Thermal Purge Time
0 min
0-20 minutes
St
Thermal Purge Start Temp
140F
140-180F
Pt
DHW Priority
ON
ON or OFF
F-C
Temperature Units
F
F or C
bAc
Exit Adjustment Mode
N/A
N/A
32
C. Using Adjustment Mode
WARNING
Improper adjustments to control parameters could result in unreliable boiler operation,
property damage, personal injury, or loss of life. Adjustments should only be made by a
qualified heating technician.
A list of parameters which can be changed on this control are shown in Table 12.5. To enter Adjustment mode and change
parameters:
1) Press and hold I, ↑, ↓ together for at least 3 seconds.
2) Use I to advance to the parameter which is to be changed.
3) Use the ↑ or ↓ buttons to change the setting or select from possible choices. See below for additional information on
the use of these parameters.
4) If other parameters are to be changed, use the I button to advance to the next parameter needing adjustment and change it
in the same way.
5) After all parameters have been changed, use the I button to advance until bAc is shown on the display.
6) Press either the ↑ or ↓ key to return to Status mode. Alternatively, the control will return to Status mode if no key is
touched for 5 minutes.
HL (High Limit Set Point) - Burner shuts down if the boiler water temperature exceeds this setting. The circulator will continue to
run. The high limit setting also serves as the water temperature set point (SP) during calls for both heat and DHW.
HdF (High Limit Differential) - If the boiler shuts off on high limit, the water temperature must fall by an amount equal to the
differential during the same call for heat before the burner will again start. For example, with HL=180 and HdF=15, the burner
will shut off if the water temperature exceeds 180F and stay off until the temperature falls to 165F (180 - 15). Note that if all calls
for heat end while the burner is off on high limit, the burner will not restart during the next call for heat until the thermal purge
requirements described below are met.
On the Warm Start Boiler Control the High Limit Differential is fixed at 10F.
ZC (ZC and ZR Terminal Functions - Cold Start Boiler Control) - Terminals ZC and ZR can be used to control a IWH circulator or
a second heating zone circulator using a 120VAC thermostat (see Section X). When ZC=dh, the L7248L assumes that an indirect
water heater circulator is connected to ZC and no thermal purge occurs upon a call for DHW before the boiler fires (see thermal
purge description below). In addition, a call for DHW will turn off the circulator connected to C1 and C2 if DHW priority (Pt) is
ON.
Setting ZC = Zr allows the second zone to be used as a heating zone. In this mode, there is no zone priority and a thermal purge
occurs regardless of whether the call for heat originates from T-T or ZR.
The use of the ZC=ELL (“External Low Limit”) is not recommended.
ZC (ZC and ZR Terminal Functions - Warm Start Boiler Control) - Terminals ZC and ZR can be used to control a second heating
zone circulator or an IWH circulator using a 120VAC thermostat or be used to enable pumps in a warm start application (see
Section X). When ZC=dh, and DWH priority (Pt) is OFF, a second heating zone circulator can be connected to ZC and L2.
Though not recommended unless the tankless heater is removed from the boiler, setting ZC=dh and DWH priority (Pt) to ON,
allows an indirect water heater circulator with priority to be connected to ZC and L2.
Setting ZC = Zr energizes the ZC terminal while the boiler is warm. The T-T or ZR inputs are a call for heat that fires the boiler
unless the boiler water temperature falls below the Low Limit Set Point minus the Low Limit Differential in which case the
primary heating circulator connected to C1 and the ZC output are de-energized.
33
Or (Circulator Overrun) - Determines how long the Heating Circulator will operate after the call for heat ends. In some cases, this
can help reduce energy consumption by sending heat stored in the boiler out into the system. At the same time, caution should
be exercised before setting this value to something other than zero. Before doing so, verify that the system will permit flow (e.g.
flow is not completely cut-off by closed zone valves) and that the overrun will not cause overheating problems.
Circulator overrun is only possible on the heating zone controlled by T-T. The ZC Circulator will not over-run, even if it is used
as a second heating zone.
PP (Thermal Purge Time) - Upon a call for heat, the boiler will prevent burner operation until either:
•
•
The water temperature drops below the Thermal Purge Start Temperature (St) OR:
The thermal purge time has passed
For some examples of this operation, see Table 12.6. If the “ZC” zone is used for space heating (ZC=Zr), this thermal purge
function will also keep the burner off at the beginning of a call from the thermostat connected to the “ZR” terminal in the manner
described above. If the “ZC” zone is being used for DHW (ZC=dh), the burners will immediately come on upon a call for DHW
as long as the water temperature is below the high limit setting.
Thermal purge is only invoked when a call for heat first appears and the boiler is not already firing. For this reason, if the boiler
is already firing in response to an call for heat, and a call for heat appears at the second zone, the boiler will continue to fire.
TABLE 12.6 EXAMPLES OF THERMAL PURGE OPERATION
Thermal Purge Settings Boiler
Example
#
Call for
Heat
From
1
T-T
N/A
2 min.
140F
130
2
T-T
N/A
2 min.
140F
150
3
ZR
DHW (ZC=dh)
2 min.
140F
150
4
Heat T’stat
on ZR
terminals
Temp at
Use of “ZC”
Start Temp Begin
Zone
Time (Pt)
(St)
Call
Boiler Behavior
Heat (ZC=Zr)
2 min.
140F
•
•
•
•
2 minutes have passed
OR
Temperature falls below 140
•
•
“ZC” Circulator starts immediately
Burner fires immediately
•
•
“ZC” Circulator starts immediately
Burner fires when either:
150
•
5
T-T
N/A
2 min.
145F
150
•
•
6
T-T
N/A
3 min.
140
34
150
“C1-C2” Circulator starts
immediately
Burner fires immediately
“C1-C2” Circulator starts
immediately
Burner fires when either:
•
2 minutes have passed
OR
Temperature falls below 140
“C1-C2” Circulator starts
immediately
Burner fires when either:
2 minutes have passed
OR
Temperature falls below 145
“C1-C2” Circulator starts
immediately
Burner fires when either:
3 minutes have passed
OR
Temperature falls below 140
St (Thermal Purge Start Temperature) - See description for Thermal Purge Time above.
Pt (DHW Priority) - If this feature is turned on, and simultaneous calls for heat and DHW are present, the heating circulator will
be forced off for as long as it takes the boiler to satisfy the call for DHW. This feature is sometimes useful when the boiler size is
marginal for the peak DHW demand, but should be used with caution as it can result in lack of heat if the DHW call is very long,
or if there is a problem with the DHW zone which causes the DHW demand to be indefinite. Figure 12.7 describes the behavior of
both the Heating and DHW Circulators with Pt turned both ON and OFF.
F-C (Temperature Units ) - Determines whether temperature units on the L7248L are displayed in F or C. Note that this selection
only applies to the temperature displayed on the LED shown in Figure 12.0. Temperature units must be selected independently on
the displays of any control options plugged into the EnviraCOM port.
bAc (Return to Status mode) - Exits adjustment mode. Any changes made to the parameters described above are saved, and
become effective, as soon as they are made; bAc only exits adjustment mode.
TABLE 12.7a SUMMARY OF CIRCULATOR BEHAVIOR - L7248L - COLD START CONTROL
Thermostat Inputs
Parameters
Circulator Outputs
Use of
DHW
“ZC”
2nd Zone Priority
T-T
“DHW”
Zone
(Zc)
(Pt)
“C1-C2”
“ZC- L2”
ON
OFF
DHW
Zc=dh
ON
ON
OFF
OFF
ON
DHW
Zc=dh
ON
OFF
ON
ON
ON
DHW
Zc=dh
ON
OFF
ON
ON
ON
DHW
Zc=dh
OFF
ON
ON
ON
OFF
DHW
Zc=dh
OFF
ON
OFF
OFF
ON
DHW
Zc=dh
OFF
OFF
ON
ON
OFF
Heat
Zc=Zr
ON or OFF
ON
OFF
OFF
ON
Heat
Zc=Zr
ON or OFF
OFF
ON
ON
ON
Heat
Zc=Zr
ON or OFF
ON
ON
*TABLE 12.7b SUMMARY OF CIRCULATOR BEHAVIOR - L7224A - WARM START CONTROL
Thermostat Inputs
Parameters
Circulator Outputs
Use of
DHW
“ZC”
2nd Zone Priority
T-T
“DHW”
Zone
(Zc)
(Pt)
“C1-C2”
“ZC- L2”
ON
OFF
DHW
Zc=dh
ON
ON
OFF
OFF
ON
DHW
Zc=dh
ON
OFF
ON
ON
ON
DHW
Zc=dh
ON
OFF
ON
ON
ON
DHW
Zc=dh
OFF
ON
ON
ON
OFF
DHW
Zc=dh
OFF
ON
OFF
OFF
ON
DHW
Zc=dh
OFF
OFF
ON
ON
OFF
Heat
Zc=Zr
ON or OFF
ON
ON
OFF
ON
Heat
Zc=Zr
ON or OFF
OFF
ON
ON
ON
Heat
Zc=Zr
ON or OFF
ON
ON
* Assumes boiler water temperature is above Low Limit Set Point.
35
XIII Service and Maintenance
WARNING
All boiler cleaning must be completed with the burner service switch turned off. Boilers
equipped with burner swing door have a potential hazard which can cause severe property
damage, personal injury or loss of life if ignored. Before opening swing door, turn off service
switch to boiler to prevent accidental firing of burner outside the combustion chamber.
Disconnect the burner plug from the receptacle in the front jacket. Be sure to tighten the
swing door fastener completely when service is completed.
The following procedure should be performed on an annual basis:
1) Turn off electrical power and oil supply to the boiler.
2) Clean the boiler as follows:
a) Remove vent connector and piping.
b) Remove barometric draft regulator.
c) Remove top jacket panel to gain access to boiler flue collector.
d) Unscrew four wing nuts and remove canopy retaining carriage bolts, lift off the canopy and ceramic fiber sealing
strips.
e) Unplug the burner, disconnect the oil lines (if the pump is hard piped), and remove the two 5/16” bolts securing the
burner door. Open the burner swing door.
f) Thoroughly brush boiler flueways from the top and diagonally between casting pin rows. Be careful when brushing the
rear passage not to damage the rear target wall insulation.
g) Vacuum soot and debris from combustion chamber.
h) Check condition of rear target wall insulation, combustion chamber liner, and burner door insulation; replace if
required.
i) Check burner head for signs of deterioration. Clean the head of any deposits. j) Close burner door, reinstall 5/16” bolts, reconnect fuel oil and electrical lines.
k) Installation of boiler canopy, jacket top panel barometric draft regulator and breeching piping is done in reverse order
of removal. Make sure canopy is sealed tight to the casting; replace ceramic fiber sealing strips as needed. All vent
piping joints must be flue gas leak free and secured with sheet metal screws.
IMPORTANT
• Clean The Boiler Even If There Are No Significant Soot Deposits. Failure To Remove All Sulfur And Ash Deposits Annually Can Cause Severe Corrosion Damage.
• When Cleaning The Rear Flue Passage, Be Careful Not To Push The Brush Too Far Beyond The Bottom Of The Pins. Doing So May Damage The Target Wall.
3) Inspect the vent system:
a) Make sure that the vent system is free of obstructions and soot.
b) Make sure that all vent system supports are intact.
c) Inspect joints for signs of condensate or flue gas leakage.
d) Inspect venting components for corrosion or other deterioration. Replace any defective vent system components.
36
WARNING
The boiler must be connected to an approved chimney in good condition. Serious property
damage could result if the boiler is connected to a dirty or inadequate chimney. The interior
of the chimney flue must be inspected and cleaned before the start of the heating season and
should be inspected periodically throughout the heating season for any obstructions. A clean
and unobstructed chimney flue is necessary to allow noxious fumes that could cause injury or
loss of life to vent safely and will contribute toward maintaining the boiler’s efficiency.
4) Service the oil burner:
a) Replace oil nozzle with identical make and model (see Table 11.0).
b) Inspect the electrodes. Replace if they are deteriorated. Make sure that the electrode position is set according to the
burner manufacturer’s instructions.
c) Remove and clean fuel pump strainer.
d) Remove any accumulations of dust, hair, etc. from the air shutter, blower wheel, and other air handling parts of the
burner.
5) Replace the fuel oil line filter element and gaskets.
6) Inspect all oil piping and fittings for kinks and leaks. Repair any found.
7) Inspect the hydronic piping, tankless coil gasket, and boiler plugs for water leaks. Repair any leaks found immediately.
8) Verify operation of relief valve by manually lifting lever; replace relief valve immediately if valve fails to relieve pressure.
9) Open fuel line shut-off valve(s) and restore electrical power to the boiler.
10) Fire the boiler and check it out using the procedure outlined in “Start-up and Checkout” . This must include checking the
burner adjustments using instruments. Check for proper operation of all controls.
WARNING
Water leaks can cause severe corrosion damage to the boiler or other system components.
Repair any leaks found immediately.
37
Important Product Safety Information
Refractory Ceramic Fiber Product
Warning:
The Parts list designates parts that contain refractory ceramic fibers (RCF).
RFC has been classified as a possible human carcinogen. When exposed to
temperatures about 1805°F, such as during direct flame contact, RFC changes
into crystalline silica, a known carcinogen. When disturbed as a result of
servicing or repair, these substances become airborne and, if inhaled, may be
hazardous to your health.
AVOID Breathing Fiber Particulates and Dust
Precautionary Measures:
Do not remove or replace RCF parts or attempt any service or repair work
involving RCF without wearing the following protective gear:
1. A National Institute for Occupational Safety and Health (NIOSH)
approved respirator
2. Long sleeved, loose fitting clothing
3. Gloves
4. Eye Protection
•
•
•
•
Take steps to assure adequate ventilation.
Wash all exposed body areas gently with soap and water after contact.
Wash work clothes separately from other laundry and rinse washing
machine after use to avoid contaminating other clothes.
Discard used RCF components by sealing in an airtight plastic bag. RCF
and crystalline silica are not classified as hazardous wastes in the United
States and Canada.
First Aid Procedures:
•
•
•
•
If contact with eyes: Flush with water for at least 15 minutes. Seek
immediate medical attention if irritation persists.
If contact with skin: Wash affected area gently with soap and water.
Seek immediate medical attention if irritation persists.
If breathing difficulty develops: Leave the area and move to a location
with clean fresh air. Seek immediate medical attention if breathing
difficulties persist.
Ingestion: Do not induce vomiting. Drink plenty of water. Seek
immediate medical attention.
38
XIV Trouble Shooting
A. Combustion
1) Nozzles - The selection of the nozzle supplied with the TWZ boiler is the result of extensive testing to obtain the best flame
shape and efficient combustion. Other brands of the same spray angle and pattern may be used but may not perform at the
expected level of CO2 and smoke. Nozzles are delicate and should be protected from dirt and abuse. Nozzles are massproduced and can vary from sample to sample. For all of those reasons a spare nozzle should be part of a serviceman’s
replacement parts inventory.
2) Flame Shape - As seen for the observation port, the flame should appear straight with no sparklers rolling up toward the
crown of the chamber. If the flame drags to the right or left, sends sparklers upward or makes wet spots on the chamber
walls, the nozzle should be replaced. If the condition persists look for fuel leaks, air leaks, water or dirt in the fuel as
described below.
3) Fuel Leaks - Any fuel leak between the pump and the nozzle will be detrimental to good combustion results. Look for wet
surfaces in the air tube, under the ignitor and around the air inlet. Any such leaks should be repaired as they may cause
erratic burning of the fuel and in the extreme case may become a fire hazard.
4) Air Leaks - Any such leaks should be repaired as they may cause erratic burning of fuel and in extreme cases may become a
fire hazard.
5) Gasket Leaks - If CO2 readings between 11.5% and 12.8% with a #1 smoke cannot be obtained in the breeching, or if odors
are observed, look for leaks around the burner mounting gasket, observation door and canopy gasket, or in the breeching
below the point where the flue gas sample is taken. Air leakage into the boiler or breeching can cause low CO2 readings (the
lower the firing rate, the greater effect an air leak can have on CO2 readings). Such leaks can also cause flue gas leakage into
the building, resulting in odor complaints.
6) Dirt - The use of a fuel filter is good practice. Accidental accumulation of dirt in the fuel system can clog the nozzle or
nozzle strainer and produce a poor spray pattern from the nozzle. The smaller the firing rate, the smaller the slots in the
nozzle and the more prone to plugging it becomes.
7) Water - Water in the fuel in large amounts will stall the fuel pump. Water in the fuel in smaller amounts will cause excessive
wear on the pump. More importantly it chills the flame and causes smoke and unburned fuel to pass through the combustion
chamber and clog the flueways of the boiler.
8) Cold Oil - If the oil temperature near the fuel pump is 40°F or lower, poor combustion or delayed ignition may result. Cold
oil is harder for the nozzle to atomize, thus the oil droplets get larger and travel further creating a longer flame. An outside
fuel tank that is above grade or has fuel lines in a shallow bury is a good candidate for cold oil. The best solution is to bury
the tank and lines deep enough to keep the oil above 40°F. Be sure to follow any state and local codes when burying fuel oil
tanks and/or fuel oil lines.
9) Start-Up Noise - Delayed ignition is the cause of start-up noises. If it occurs recheck for electrode settings, flame shape, air
or water in the fuel lines.
10) Shut Down Noise - If the flame runs out of air before it runs out of fuel, an after burn with noise may occur. That may be the
result of a faulty cut-off valve in the fuel pump, or it may be air trapped in the nozzle line. It may take several firing cycles
for that air to be fully vented through the nozzle. Water in the fuel or poor flame shape can also cause shut down noises.
TEST PROCEDURE FOR FUEL SIDE PROBLEMS
A good test for isolating fuel side problems is to disconnect the fuel system and with a 24”
length of tubing, fire the burner out of an auxiliary five gallon pail of clean, fresh, warm #2 fuel
oil from another source. If the burner runs successfully when drawing out of the auxiliary pail
then the problem is isolated to the fuel or fuel lines being used on the installation.
39
B. Control System
The following pages contain trouble shooting tables for use in diagnosing control problems. When using these tables the
following should be kept in mind:
1) This information is only meant to be used by a professional heating technician as an aid in diagnosing boiler problems.
2) Where applicable, follow all precautions outlined in the Section XI (Start-up and Checkout).
3) In general, these tables assume that there are no loose or miswired electrical connections. Before using these tables inspect
all electrical connections on the boiler to make sure that they are tight. Also, check the wiring on the boiler against the wiring
diagram in Figures 10.0 or 10.1 and 10.2,as appropriate for the boiler model. Ensure that incoming 120 VAC power polarity
is correct and that the boiler is properly grounded.
4) All controls on the boiler are tested at least once in the manufacturing process and a defective control or component is
generally the least likely cause. Before replacing a component, try to rule out all other possible causes.
C. If Display is Blank
Check for 120 VAC across L1 and L2. If voltage not present turn on system power. If voltage is present check polarity. If
polarity is correct replace the control.
D. If Control Shows Err Code
Use Table 14.0 to help identify and correct the cause of the problem.
E. If Control Shows StA Code, but Other Problem Present
If no Err Code is observed (even after repeatedly pressing I to cycle through Operation Mode), use Table 14.1 to help identify
and correct the cause of the problem.
TABLE 14.0 - ERROR CODES
Error
Code Meaning
Possible Cause
1
Temperature Sensor Fault
2
Communication Fault
3
Internal electronics failure
•
•
•
•
•
•
•
•
4
Burner Output (B1) Fault
•
•
5
Line voltage error
(Supply voltage too high or low)
•
Loose connection between sensor and control
Sensor wire damaged
Defective Sensor
Defective control
EnviraCOM wiring is shorted to ground or line voltage
Field wiring to external Enviracom device is incorrect.
AC power supply frequency problem
Possible internal problem with boiler control. Cycle power to the boiler and
replace control if problem persists.
Application of power to B1 from external source (control miswired)
Possible internal problem with boiler control. Cycle power to the boiler and
replace control if problem persists.
Power supply voltage is incorrect (should be 120VAC nominal)
6
Open fuse in L7248L or L7224A
•
Incorrectly wired burner primary control (See Section X).
7
8
User settings lost (reset to factory •
defaults)
•
Manual Reset Lockout
Clear error by entering and exiting the Adjustment mode (and changing settings back to user values as needed). Replace control if problem persists.
Set if Err 4 was invoked four times in a row. Check wiring and clear Lockout
by pressing all three user keys for 60 seconds.
40
TABLE 14.1 - FAULTS WITHOUT ERROR CODE PRESENT
Displayed
Codes
Problem
Possible Cause
Burner and
Circulator Off
•
•
•
•
Thermostat/s not calling for heat
Loose connection in thermostat, zone valve end switch, or zone panel wiring.
Thermostat, zone valve, or zone panel miswired
Defective thermostat, zone valve, or zone panel
StA 1
hr On
Burner Off
Circulator On
Boiler Warm
•
•
Boiler off on high limit (normal operation)
Boiler off on thermal purge (normal operation - See Table 12.6)
hr On
Heating
Circulator Off
•
•
•
•
•
Heating Circulator is being forced off on DHW priority (normal operation if Pt=ON see Table 12.7).
See causes for “DHW Circulator off “ below
Loose connection in circulator wiring
Defective circulator
Circulator is running, but system problem is preventing circulation
•
•
•
•
External Limit or LWCO is open.
Burner is unplugged
Loose connection between B1-B2 on L7248L or L7224A and burner
Loose or missing T-T jumper on burner primary control.
•
Consult burner documentation for cause of problem.
StA 1
hr OFF
dh OFF
dh On
StA 8
StA 8
DHW
Circulator Off
Burner Off
No LEDs
illuminated
on Burner
Primary
control
Burner Off
LED is
illuminated
on Burner
Primary
control
41
XV Parts
KEY #
1
DESCriPTiOn
HEAT EXCH ASSY. WITH COIL OPENING
QTY. Or CrOWn
P.n.
QUanTiTY PEr BOiLEr Or CrOWn P.n.
65
75
100
90
125
150
120
175
200
1 ea.
270013
270013
270013
270014
270014
270014
270015
270015
270015
2700155
1
HEAT EXCH ASSY. LESS COIL OPENING
1 ea.
2700135
2700135
2700135
2700145
2700145
2700145
2700155
2700155
*
FRONT SECTION WITH COIL OPENING
275050
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
*
FRONT SECTION LESS COIL OPENING
275052
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
*
REAR SECTION
275060
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
*
INTERMEDIATE SECTION
275055
1 ea.
1 ea.
1 ea.
2 ea.
2 ea.
2 ea.
3 ea.
3 ea.
3 ea.
*
LOWER PUSHNIPPLE
275070
2 ea.
2 ea.
2 ea.
3 ea.
3 ea.
3 ea.
4 ea.
4 ea.
4 ea.
*
UPPER PUSHNIPPLE
275075
2 ea.
2 ea.
2 ea.
3 ea.
3 ea.
3 ea.
4 ea.
4 ea.
4 ea.
2
BURNER SWING DOOR HINGE (STANDARD)
275030
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
3
FRONT SECTION HINGE (STANDARD)
275035
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
4
SWING DOOR INSULATION
270021
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
5
5/16-18 X 1-1/2 HX HEAD CAP SCREW
900415
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
6
5/16 FLAT WASHER
900102
10 ea.
10 ea.
10 ea.
10 ea.
10 ea.
10 ea.
10 ea.
10 ea.
10 ea.
7
5/16-18 X 1 HX HEAD CAP SCREW
900410
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
8
FLAME INSPECTION COVER
270022
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
9
5/16-18 X 3/4 HEX HEAD CAP SCREW
900400
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
10
TARGET WALL (REPLACEMENT KIT)
270025
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
11
REFRACTORY BLANKET
1 ea.
275003
275003
275003
275004
275004
275004
275005
275005
275005
12
SWING DOOR (STANDARD)
270020
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
13
BURNER SWING DOOR HINGE (ALTERNATE)
290035
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
15
FLAME INSPECTION COVER (ALTERNATE)
290022
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
14
SWING DOOR (ALTERNATE)
290020
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
20
1/2" x 1" SEALING STRIP
900145
4.0 ft
4.0 ft
4.0 ft
4.8 ft
4.8 ft
4.8 ft
5.7 ft
5.7 ft
5.7 ft
21
FLUE COLLECTOR
1 ea.
270123
270123
270123
270124
270124
270124
270125
270125
270125
22
1/4-20 x 3" CARRIAGE BOLT
900126
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
23
1/4-20 x 3-1/2" CARRIAGE BOLT
900127
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
2 ea.
24
1/4" USS FLAT WASHER
90-215
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
25
1/4-20 WING NUT
900125
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
4 ea.
30
TANKLESS HEATER GASKET
270001
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
31
TANKLESS HEATER (OPTIONAL)
270002
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
33
3/8-16 X 7/8 HX HEAD CAP SCREW
900450
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
34
3/8 USS FLAT WASHER
90-036
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
6 ea.
† SEE PAGE 26 FOR WARNING REGARDING THE HANDLING OF PARTS THAT CONTAIN REFRACTORY CERAMIC FIBERS.
42
43
KEY #
DESCriPTiOn
40
REVERSIBLE SIDE JACKET PANEL (RED)
40
REVERSIBLE SIDE JACKET PANEL (GRAY)
*
REAR JACKET PANEL
QUanTiTY PEr BOiLEr Or CrOWn P.n.
QTY. Or CrOWn
P.n.
65
75
100
90
125
150
120
175
200
2 ea.
270523
270523
270523
270524
270524
270524
270525
270525
270525
290225
2 ea.
290223
290223
290223
290224
290224
290224
290225
290225
290220
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
290543
290543
290543
290544
290544
290544
290545
290545
290545
1 ea.
43
SPLIT REAR TOP JACKET PANEL
44
FRONT JACKET PANEL
290510
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
45
SPLIT FRONT TOP JACKET PANEL
290215
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
46
#10 X 1/2" SHEET METAL SCREW
90-212
15 ea.
15 ea.
15 ea.
15 ea.
15 ea.
15 ea.
15 ea.
15 ea.
15 ea.
47
5/16-18 X 1/2 PAN HEAD SCREW
900420
8 ea.
8 ea.
8 ea.
8 ea.
8 ea.
8 ea.
8 ea.
8 ea.
8 ea.
48
1/2" LONG WELL (WITH COIL)
35-1006
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
48
1/2" SHORT WELL (LESS COIL)
35-1005
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
49
AQUASTAT (L7224A----) (WITH COIL)
3503----
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
49
AQUASTAT (L7248L1100) (LESS COIL)
3503025
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
51
JUNCTION BOX
96-001
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
54
TWIST RECEPTICAL
96-010
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
55
TWIST RECEPTICAL UTILITY BOX COVER
96-019
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
55
BLANK UTILITY BOX COVER
96-002
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
56
TRIDICATOR GAUGE
95-069
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
130519
THE FOLLOWing BUrnErS HaVE TWiST LOCK PLUgS
60
BECKETT BURNER ASSY. (NOTE #1)
1 ea.
130511
130512
130513
130514
130515
130516
130517
130518
60
CARLIN BURNER ASSY. (NOTE #1)
1 ea.
130521
130522
130523
130524
130525
130526
130527
130528
60
RIELLO BURNER ASSY. (NOTE #1)
1 ea.
130532
130533
130535
130536
130538
130539
130299
THE FOLLOWing BUrnErS HaVE QUiCK COnnECT PLUgS FOr MaKing COnnECTiOn inSiDE JUnCTiOn BOX
60
BECKETT BURNER ASSY. (NOTE #1)
1 ea.
130291
130292
130293
130294
130295
130296
130297
130298
60
CARLIN BURNER ASSY. (NOTE #1)
1 ea.
130391
130392
130393
130394
130395
130396
130397
130398
61
5/16-18 X 1 HEX HD SCW (BURNER MOUNT)
900410
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
5/16 FLAT WASHER (BURNER MOUNT)
900102
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
3 ea.
70
3/4" RELIEF VALVE (30 psi)
95-040
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
71
CIRCULATOR (TACO 007)
95-012
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
*
1-1/2" TACO FLANGE SET
950150
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
*
3/4" BOILER DRAIN
95-041
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
1 ea.
*
* NOT PICTURED
NOTE #1: PART NUMBERS PROVIDED ARE FOR FULLY CONFIGURED BURNERS AND INCLUDE NOZZLES, BURNER CORD
ASSEMBLIES, AND (WHERE APPLICABLE) LOW FIRING RATE BAFFLES.
44
45
Manufacturer of Hydronic Heating Products
P.O. Box 14818 3633 I. Street
Philadelphia, PA 19134
www.crownboiler.com
46
PN: 980270 Rev 10
TWZ - 12/12
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertising