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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 DO NOT USE BOILER DURING CONSTRUCTION follow the requirements given on page 9.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — How it works . . . 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 550-142-302/0124...
Therefore, • Do not use petroleum-based cleaning or sealing com- Weil-McLain equipment contaminated with saltwater or pounds in boiler system. Water seal deterioration will polluted water will no longer be covered under warranty occur, causing leakage between sections.
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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 ordi- nances. • 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 recommendations.
Condensation can return doors, windows, exhaust fans, fireplace damage a masonry chimney. Weil-McLain dampers, and any other gas-burning appliance recommends the following to prevent pos- to their previous conditions of use.
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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 Please review the following information on poten- Table 1 cause contaminated combustion air. tial 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 the boiler. Check the boiler placement compared to Figure 1a, page 7.
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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 Unusually tight construction means (per ANSI area, length times width of opening, after deduc- Z223.1/NFPA 54) buildings in which: tion for 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 550-142-302/0124...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Prepare boiler — pressure test Hydrostatic pressure test 4. Close shutoff valves. 5. Slowly reopen boiler drain valve until test Pressure test boiler attaching water or gas before pressure on the pressure/temperature gauge piping (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 Chimney draft venting uses the natural draft pro- Direct exhaust venting uses inside combustion air vided by a vertical vent or chimney.
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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 and ULC-S636 standards and are certified by CSA as the only Max.
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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 3. Follow all applicable national, state, local or all vent components needed, based on boiler provincial codes when venting the CGi boiler. location and venting method.
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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 ac- cumulate 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 Figure 15 Sidewall termination shown could cause nuisance outages and loss of heat, resulting in substantial property damage. Part Number 550-142-302/0124...
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, The circulator is shipped loose (wiring pre-attached an additional maybe needed. Install control in to boiler) to allow you to locate it either in the re- high temperature limit supply piping 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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Instead, provide controls and piping which can regulate the boiler return water temperature at no less than 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.1...
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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) Automatic air vent (with diaphragm-type expansion tank), or valves connect to tank fitting (closed-type expansion tank).
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Instead, provide controls and piping which can regulate the boiler return water temperature at no less than 130°F regardless of system supply tem- perature. 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 — Piping — low temperature systems (continued) Figure 20 Primary/secondary piping Figure 21 Primary/secondary piping Zoning with circulators Zoning with zone valves 1 Boiler isolation (balancing) valves 9 Relief valve 10 Automatic air vent (with diaphragm-type expansion tank), 2 Flow/check valve or connect to tank fitting (closed-type expansion tank).
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Instead, provide controls and piping which can regulate the boiler return water temperature at no less than 130°F regardless of system supply temperature. Contact your Weil-McLain representative for suggested pip- ing and control methods. Failure to prevent cold return water temperature to the boiler could cause cor- rosion 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 temperature. 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 Table 7 rated boiler input (divide by 1,000 to obtain cubic feet 1.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Field wiring For your safety, turn off electrical power sup- plus gas valve current. See information on wiring diagram ply at service entrance panel before making as shown in Figure 32, page 39. For other devices, refer any electrical connections to avoid possible to manufacturer’s specifications.
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 Do not use petroleum-based cleaning or sealing during initial operation, smell in boiler system. Severe damage to compounds near the floor and around the boiler will occur, resulting in substantial property...
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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. air vents After filling the boiler and system with water, 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 DO NOT instructions 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 Main burner flame ( Operating instructions Figure 29 start the boiler. PROPER main burner flame characteristics • if boiler fails to start. Section 7c 1.
Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Check-out procedure — checklist e. Pilot will relight, flame sensing element will sense Boiler and heat distribution units filled with water? pilot flame and main burners will reignite. Automatic air vent, if used, open one full turn? Set limit control(s) to system temperature require- Air purged from system? ments.
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 Lower valves are 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 550-142-302/0124...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Operation — wiring diagrams (continued) Figure 32 Ladder wiring diagram Part Number 550-142-302/0124...
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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 550-142-302/0124...
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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 550-142-302/0124...
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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 550-142-302/0124...
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 Air openings 1. Verify that combustion and ventilation air open- The boiler should be ings to the boiler room and/or building are open inspected and started an- unobstructed , at the beginning of the heating season, nually...
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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 Burners and base front panels.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service & maintenance – annual start-up (cont.) Check/test . . . type. See Section of this manual for suggested best location of expansion tanks and air elimina- tors. Gas piping — located above highest radiator or Open-type baseboard unit, usually in the attic or closet.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Service & maintenance – annual start-up (cont.) Review with owner Safety relief valves should be reinspected , by a AT LEAST ONCE EVERY THREE YEARS licensed plumbing contractor or authorized 1. Review the with the User’s Information Manual inspection agency, to ensure that the prod-...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — procedure Check the following: Label all wires prior to dis- connection when servicing 1. Wire connectors to control module are securely plugged in at controls. Wiring errors can module and originating control. cause improper and dan- 2.
— 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) Control indicator lights — The information on this page and pages 52 through 60 ap- LOCKOUT modes ply only to spark-ignited pilot See Charts 1 through 8 in this section for detailed trouble- CGi boilers.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — components (continued) Figure 38 Control module connections Part Number 550-142-302/0124...
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• Replace transformer. licensed electrician. • Replace control module. • Retest and check for • If problem persists, contact back feed of voltage from • Boiler should now • Retest. your Weil-McLain Technical system wiring. operate normally. support. Part Number 550-142-302/0124...
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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 — Wherever you see ▲ TURN OFF POWER ▲, follow the instructions. Failure to follow instructions could result in severe personal injury, death or substantial property damage.
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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 — Wherever you see ▲ TURN OFF POWER ▲, follow the instructions. Failure to follow instructions could result in severe personal injury, death or substantial property damage.
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Troubleshooting — control module lights (cont.) CHART 4 –– FLAME & POWER light flashing –– Usually indicates flame sensed when it shouldn’t be there –– Electrical shock hazard — Wherever you see ▲ TURN OFF POWER ▲, follow the instructions. Failure to follow instructions could result in severe personal injury, death or substantial property damage.
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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 —...
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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 — Wherever you see ▲ TURN OFF POWER ▲, follow the instructions. Failure to follow instructions could result in severe personal injury, death or substantial property damage.
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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 — Wherever you see ▲ TURN OFF POWER ▲, follow the instructions. Failure to follow instructions could result in severe personal injury, death or substantial property damage.
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10.0” w.c. on propane? • See Figure 30, page 38 continuity – for normal sequence of operation. Is switch closed? • 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 550-142-302/0124...
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 550-142-302/0124...
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Panel, right side, Panel, top front, Panel, top rear, 2 x 4 with insulation with insulation with insulation with insulation Natural Gas Propane Gas Boiler Boiler Weil-McLain part number Model Model CGi-25 (Available at 381-359-215 381-359-222 381-359-229 381-359-230 381-359-242 CGi-25 CGi-3...
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Boiler Manual 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 383-500-095 (Fittings shown are factory-installed on boiler.) Combination pressure-temperature gauge, 3Z\,” diameter, short shank 380-000-000 (Fittings shown are shipped loose with boiler.)
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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 -6 511-044-381 511-044-353 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 INSTALLATION OF FIBERGLASS or base insulation panels in this WOOL, product contain ceramic fiber materials that have been identified...
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Boiler Manual SERIES 4 — GAS-FIRED WATER BOILER — Part Number 550-142-302/0124...