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Series 4 Gas-Fired Water Boilers Boiler Manual • Installation • Maintenance • Startup • Parts Now With Built In Low Water Cut Off Functionality Blower cover on sizes CGi 25-6 only unless you provide dust-free air to the boiler area or follow DO NOT USE BOILER DURING CONSTRUCTION the requirements given on page 9.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — How it works . . . ① Control module The control module responds to signals from the room thermostat, air pressure switch and boiler limit circuit to operate the boiler circulator, pilot burner, gas valve and inducer. When room thermostat calls for heat, the control module starts the system circulator and inducer.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — CGi Series 4 Gas-Fired Induced-Draft Water Boiler Part Number 550-142-302/0520...
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Contents How it works ............ 2 Hazard definitions ..........4 Please read before proceeding ......5 Prepare boiler location ........6–11 Prepare boiler ..........12–13 Venting ............14-19 Water piping ..........20-29 Gas piping ............
Boiler water — water is gone due to the conductive and corrosive nature of the salt residue. Therefore, Weil-McLain equipment contaminated • Do not use petroleum-based cleaning or sealing com- with saltwater or polluted water will no longer be covered under pounds in boiler system.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler location — codes & checklist Installations must follow these codes: • Local, state, provincial, and national codes, laws, regulations and ordinances. • National Fuel Gas Code, ANSI Z223.1/NFPA 54 – latest edition. •...
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler location — clearances Recommended SERVICE clearances Figure 1b Required MINIMUM clearances (Fig. 1a) 1. Provide clearances for cleaning and servicing the boiler and for access to controls and components. See Figure 1a for recommen- dations.
Condensation properly vents when tested as outlined above, return can damage a masonry chimney. Weil-McLain doors, windows, exhaust fans, fireplace dampers, and recommends the following to prevent possible any other gas-burning appliance to their previous con- damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler location — air contamination Refer to for products and areas which may cause Please review the following information on potential Table 1 contaminated combustion air. combustion air contamination problems. To prevent potential of severe personal injury or death, check for products or areas listed below before installing boiler.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler location — air openings Figure 2 Air openings to interior spaces Combustion air opening location and sizing ✷ requirements depend on the clearances around Check the boiler placement compared to the boiler.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler location — air openings Unusually tight construction of openings — the minimum areas FREE AREA given in this manual are free area (equals the area, Unusually tight construction means (per ANSI Z223.1/ length times width of opening, after deduction for NFPA 54) buildings in which: louver obstruction).
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2,000-4,500 Canada CGi-25 2.30 mm CGi-3 and CGi-5 2.55 mm 1.60 mm 1.45 mm CGi-4, CGi-6 - CGi-8 2.70 mm 1.65 mm Note 1: For elevations above 2,000 feet, contact your local Weil-McLain sales office for details. Part Number 550-142-302/0520...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler — pressure test 5. Slowly reopen boiler drain valve until test pressure Hydrostatic pressure test on the pressure/temperature gauge reaches no more Pressure test boiler attaching water or gas piping before than: (except as noted below) or electrical supply.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Venting — general information CGi venting methods — Chimney draft or Direct exhaust Chimney draft venting Direct exhaust — vertical or sidewall Direct exhaust venting uses inside combustion air with Chimney draft venting uses the natural draft provided no combustion air connector piping.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Venting — Direct exhaust — components Obtain vent system components Table 4 Maximum vent length 1. The following special gas vent systems comply with UL-1738 (Note 1) Max. vent Total number of elbows and ULC-S636 standards and are certified by CSA as the only length (feet) systems suitable for use with CGi boilers (all 3”...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Venting — direct exhaust — vent starter 1. Select a vent pipe manufacturer and obtain all vent 3. Follow all applicable national, state, local or provin- components needed, based on boiler location and cial codes when venting the CGi boiler.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Venting — direct exhaust — termination The vent termination must be located to meet all requirements below (also applies to vertical vent terminations). The minimum distance from adjacent public walkways, adjacent buildings, openable windows and building in the National Fuel Gas Code, ANSI Z223.1/NFPA 54 –...
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• Vent is sloped toward termination as shown in dotted lines in Figure 14 • The vent is installed per Weil-McLain and vent manufacturer’s instructions. • Condensate drip page from such vents may accumu- late on the ground below. Consider traffic in the area to avoid hazard due to ice accumulation.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Venting — direct exhaust — installation (cont.) Using any termination other than one of those shown Figure 15 Sidewall termination could cause nuisance outages and loss of heat, resulting in substantial property damage. Part Number 550-142-302/0520...
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Water piping — general information General piping information Circulator If installation is to comply with ASME or Canadian requirements, an ad- The circulator is shipped loose (wiring pre-attached to ditional maybe needed. Install control in supply piping boiler) to allow you to locate it either in the return or high temperature limit between boiler and isolation valve.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Water piping — single-zone system Undersized expansion tanks cause system water to be lost from relief valve and makeup water to be added through fill valve. Eventual section failure can result. Diaphragm-type or bladder- Closed-type expansion tank type expansion tank...
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130°F regardless of system supply temperature. Contact your Weil-McLain representative for suggested piping and control methods. Failure to prevent cold return water temperature to the boiler could cause corrosion damage to the sections or burners, resulting in possible severe personal injury, death or substantial property damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Water piping — multiple zones (continued) Figure 18 Zoning with circulators Figure 19 Zoning with zone valves — return water 130°F or higher. — return water 130°F or higher. Boiler isolation (balancing) valves Automatic air vent (with diaphragm-type expansion tank), or con- nect to tank fitting (closed-type expansion tank).
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130°F Contact your Weil-McLain representative for suggested piping and control methods. Failure to to the boiler could cause corrosion prevent cold return water temperature damage to the sections or burners, resulting in possible severe personal injury, death or substantial property damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Piping — low temperature systems (continued) Figure 20 Primary/secondary piping Figure 21 Primary/secondary piping Zoning with circulators Zoning with zone valves Boiler isolation (balancing) valves Relief valve Automatic air vent (with diaphragm-type expansion tank), or Flow/check valve connect to tank fitting (closed-type expansion tank).
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130°F Contact your Weil-McLain representative for suggested piping and control methods. Failure to to the boiler could cause corrosion prevent cold return water temperature damage to the sections or burners, resulting in possible severe personal injury, death or substantial property damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Piping — low temperature systems (continued) Figure 22 Boiler-bypass piping — Zoning with Figure 23 Boiler-bypass piping — Zoning with circulators — (Alternative to primary/ zone valves — (Alternative to primary/ secondary piping Figures 20 and 21) secondary piping Figures 20 and 21) Boiler isolation (balancing) valves...
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130°F Contact your Weil-McLain representative for suggested piping and control methods. Failure to to the boiler could cause corrosion prevent cold return water temperature damage to the sections or burners, resulting in possible severe personal injury, death or substantial property damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Piping — low temperature systems (continued) Figure 24 System-bypass piping — Zoning with zone valve or circulators, return water 130°F or higher — (Alternative to boiler- bypass piping Figures 22 and 23) 3 System or zone circulator 7 System temperature valves (see instructions to the left for adjusting valves)
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Gas piping Natural Gas: Connecting gas supply piping to boiler 1. Refer to for pipe length and diameter. Base on rated Table 7 boiler input (divide by 1,000 to obtain cubic feet per hour). 1.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Field wiring For your safety, 3. If thermostat has a heat anticipator, set heat anticipator in turn off electrical power supply thermostat to match power requirements of equipment con- at service entrance panel before making any to avoid possible electric nected to it.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Start-up — preparation Check for gas leaks Determine if water treatment is needed Before starting the boiler, and dur- Do not use petroleum-based cleaning or sealing ing initial operation, smell near the in boiler system.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Start-up — preparation (continued) Fill the system with water Inspect system water piping 1. Close manual and automatic and boiler drain cock. After filling the boiler and system with water, air vents inspect all throughout the system for leaks.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Start-up — operate boiler proceed with boiler operation unless boiler and system have been filled with water and all instructions DO NOT and procedures of previous manual sections have been completed. Failure to do so could result in severe personal injury, death or substantial property damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Start-up — operate boiler (continued) Start the boiler • Follow the from Section to start Operating instructions Main burner flame ( Figure 29 the boiler. PROPER main burner flame characteristics • if boiler fails to start.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Check-out procedure — checklist ❏ ❏ Boiler and heat distribution units filled with water? Set limit control(s) to system temperature requirements. Adjust balancing valves and controls to provide design ❏ Automatic air vent, if used, open one full turn? temperature to system.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Department of Energy – Compliance This boiler is equipped with a control system that automatically adjusts a time delay period to turn on the boiler during a call for heat. This is accomplished by circulating available hot water in the system while measuring water boiler water temperature changes.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operation — sequence (continued) — The circulator continues to operate. room thermostat setting to stop call for heat. Thermostat is satisfied — Pilot and main gas valves are Lower closed — Inducer operates for 15-second postpurge — Circulator is shut off. 8.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operation — wiring diagrams Figure 31 Schematic wiring diagram Part Number 550-142-302/0520...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operation — wiring diagrams (continued) Figure 32 Ladder wiring diagram Part Number 550-142-302/0520...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operating instructions CGi-25 thru -6 • Spark pilot • Natural or propane gas • Gas valve: Honeywell VR8204/VR8304 Part Number 550-142-302/0520...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operating instructions • Spark pilot • Natural or propane gas CGi-25 thru -6 • Gas valve: White-Rodgers 36E Part Number 550-142-302/0520...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operating instructions • Spark pilot • Natural or propane gas CGi-25 thru -8 • Gas valve: White-Rodgers 36C Part Number 550-142-302/0520...
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service and maintenance — schedule VERIFY PROPER OPERATION AFTER SERVICING Table 8 Service and maintenance schedules Service technician Owner maintenance (see following pages for instructions) (see CGi User’s Information Manual for instructions) •...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service and maintenance — annual start-up 2. Verify that boiler vent discharge is clean and free of obstructions The boiler should be inspected and started annu- Flue gas vent system , at the beginning of the heating season, ally only by a .
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service & maintenance – annual start-up (cont.) ❏ Inspect . . . 4. Reinstall components, starting with the burner tray, then the pilot bracket assembly, burner baffle, and air inlet top and front panels. Burners and base 5.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service & maintenance – annual start-up (cont.) ❏ — located above highest radiator or Check/test . . . Open-type baseboard unit, usually in the attic or closet. Has a gauge glass and overflow pipe to a drain. Gas piping 1.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service & maintenance – annual start-up (cont.) ❏ Safety relief valves should be Review with owner reinspected AT , by a LEAST ONCE EVERY THREE YEARS licensed plumbing contractor or authorized 1.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — procedure Label all wires prior to dis- Check the following: connection when servicing 1. Wire connectors to control module are securely plugged in at module controls. Wiring errors can and originating control.
— remove tees and reinstall hoses to air pressure switch. Table 10 Temperature/LWCO sensor resistance values Table 9 Pressure switch setpoint (for elevations above 2,000 ft., contact your local Weil-McLain Technical Service office for details.) Sensor resistance values Boiler model number Inches W.C. Sensor ohms Sensor ohms Temp.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — components (continued) The information on this page and Control indicator lights — pages 52 through 60 apply only to LOCKOUT modes spark-ignited pilot CGi boilers. See Charts 1 through 8 in this section for detailed troubleshoot- These boilers are equipped with ing procedures.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — components (continued) Figure 38 Control module connections Part Number 550-142-302/0520...
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Have system checked by a Replace transformer. licensed electrician. Retest and check for back Replace control module. feed of voltage from If problem persists, contact Boiler should now Retest. system wiring. your Weil-McLain Technical operate normally. support. Part Number 550-142-302/0520...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — control module lights (cont.) CHART 2 –– TSTAT CIRC & POWER light flashing –– Usually indicates 48 VAC on thermostat circuit (stray voltage) –– Electrical shock hazard ² :KHUHYHU \RX VHH IROORZ WKH LQVWUXFWLRQV )DLOXUH WR IROORZ TURN OFF POWER LQVWUXFWLRQV FRXOG UHVXOW LQ VHYHUH SHUVRQDO LQMXU\ GHDWK RU VXEVWDQWLDO SURSHUW\ GDPDJH...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — control module lights (cont.) CHART 3 –– PURGE & POWER light flashing –– Usually indicates pressure switch stuck closed or failed to make within 5 minutes –– Electrical shock hazard ² :KHUHYHU \RX VHH IROORZ WKH LQVWUXFWLRQV )DLOXUH WR IROORZ TURN OFF POWER LQVWUXFWLRQV FRXOG UHVXOW LQ VHYHUH SHUVRQDO LQMXU\ GHDWK RU VXEVWDQWLDO SURSHUW\ GDPDJH...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — control module lights (cont.) CHART 5 –– PURGE light flashing and POWER light on steady –– Usually indicates pressure switch opened during run cycle –– –– May also be caused by wind gusts in excess of 31 mph for non-direct vent sidewall-vented boilers –– Electrical shock hazard ²...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — control module lights (cont.) CHART 6 –– FLAME light flashing and Power light on steady Also –– Troubleshooting failure to establish main flame. Electrical shock hazard ² :KHUHYHU \RX VHH IROORZ WKH LQVWUXFWLRQV )DLOXUH WR IROORZ TURN OFF POWER LQVWUXFWLRQV FRXOG UHVXOW LQ VHYHUH SHUVRQDO LQMXU\ GHDWK RU VXEVWDQWLDO SURSHUW\ GDPDJH...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — control module lights (cont.) Troubleshooting LWCO and POWER light Solid CHART 7 –– and/or “LCO” shown on display Electrical shock hazard ² :KHUHYHU \RX VHH IROORZ WKH LQVWUXFWLRQV )DLOXUH WR IROORZ TURN OFF POWER LQVWUXFWLRQV FRXOG UHVXOW LQ VHYHUH SHUVRQDO LQMXU\ GHDWK RU VXEVWDQWLDO SURSHUW\ GDPDJH Is boiler pressurized?
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10.0” w.c. on propane? • See Figure 30, page 38 continuity – for normal sequence of operation. +U UYKVEJ ENQUGF! • Contact Weil-McLain • Check heat loss calculation Technical support or versus boiler size. replace gas valve. • Replace rollout switch.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Notes Part Number 550-142-302/0520...
Trim ....................67 Controls ..................68 Replacement parts must be purchased through a local Weil-McLain distributor. When ordering, specify boiler model and size and include description and part number of replacement part. Results from using modified or other manufactured parts will not be covered by warranty and may damage boiler or impair operation.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Replacement parts — section assembly Figure 39 Section assembly Item Description Weil-McLain Item Description Weil-McLain part number part number Washer, ⁷⁄₁₆” (1 per tie rod) End section, left hand, 51124 311-103-851...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Replacement parts — base Figure 40 Base assembly Weil-McLain Item Description part number Base assembly kit CGi-25 & CGi-3 381-354-337 (includes base panels items 1, 2, 3, 4, 5, 6 and 7)
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Replacement parts — base (continued) Part Number 550-142-302/0520...
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3DQHO right side 3DQHO top front 3DQHO top rear 2 x 4 ZLWK LQVXODWLRQ ZLWK LQVXODWLRQ ZLWK LQVXODWLRQ ZLWK LQVXODWLRQ 1DWXUDO *DV 3URSDQH *DV Boiler Boiler Weil-McLain part number Model Model CGi-25 $YDLODEOH DW 381-359-215 381-359-222 381-359-229 381-359-230 381-359-242 CGi-25 CGi-3...
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SERIES 4 — GAS-FIRED WATER BOILER — Replacement parts — trim Figure 42 Trim assembly Item Description Weil-McLain number part number Pressure relief valve, ASME, 30 PSIG, ¾” male inlet 511-546-920 Pressure relief valve, ASME, 30 PSIG, ¾” female inlet...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Replacement parts — controls Figure 43 Gas control assembly Item Description Boiler model Weil-McLain number part number Natural gas components Gas valve, ½” x ½” CGi-25 thru -6 511-044-381 511-044-381 511-044-353 ¾...
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Handling ceramic fiber and fiberglass materials REMOVAL OF COMBUSTION CHAMBER REMOVAL OF FIBERGLASS WOOL LINING OR BASE PANELS The combustion chamber lining or base INSTALLATION OF FIBERGLASS WOOL, insulation panels in this product con- COMBUSTION CHAMBER LINING OR tain ceramic fiber materials that have been identified as carcinogenic, or possibly...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Part Number 550-142-302/0520...
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