Weil-McLain 550-110-260/0107 manual How it works

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GOLD CGs Gas-Fired Water Boiler — Boiler Manual

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.

The control module runs the inducer long enough to purge the boiler flue passages, then opens the pilot valve and activates pilot ignition spark.

The control module allows up to 15 seconds to establish pilot flame. If flame is not sensed within 15 seconds, the control module will turn off the gas valve, flash the Flame light, and then enter a 15-second postpurge. The control module will then start a new cycle. This will continue indefinitely until pilot flame is established or power is interrupted. Once pilot flame is proven, the control module opens the gas valve to allow main burner flame.

When the room thermostat is satisfied, the control module turns off the gas valve, operates the inducer for a 15-second postpurge and waits for the next heat call.

The control module indicator lights show normal sequence when the lights are on steady. When a problem occurs, the control module flashes combinations of lights to indicate the most likely reason for the problem (see page 45).

Transformer

The control transformer reduces line voltage to 24 volts for the gas valve and limit circuit.

Inducer

The inducer pulls flue gases through the boiler, causing air to be pulled in through the air intake opening. The inducer pushes the flue gases through the vent pipe as well.

Air pressure switch

The air pressure switch signals the control module, telling the control module whether air is moving through the inducer.

Water temperature limit switch

The water temperature limit switch turns off the gas valve if the temperature in the boiler goes above its setting. (The circulator will continue to run as long as there is a call for heat.)

Boiler circulator

The boiler circulator circulates water through the external (system) piping. The circulator is shipped loose, and can be mounted on either the boiler supply or return piping. The factory- installed circulator wiring harness provides ample length for either location. NOTE — The control module provides a pump exercising routine. If the boiler is not operated for 30 days, the control module will power the circulator for 30 seconds, then turn off.

Other boiler components:

a

supply to system

f

pressure/temperature gauge

k

pilot burner and bracket

b

return from system

g

relief valve (not visible)

l

stainless steel burners

c

combustion air inlet

h

air vent connection

m cast iron boiler sections

d

flue outlet

i

flame rollout switch

n

flue collector

e

gas valve

j

air inlet box

o

junction box



Part number 550-110-260/0107

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Contents Gold CGs How it works Gold CGs Gas-Fired Induced-Draft Water Boiler Contents User InstallerPlease read before proceeding Before locating the boiler, check the following 1a Prepare boiler location codes & checklistInstallations must follow these codes 1b Prepare boiler location clearances CGs special vent system When removing boiler from an existing common vent system1c Prepare boiler location vent system Vent system1d Prepare boiler location contamination Products to avoidSpecial considerations 1e Prepare boiler location air openingsCombustion air options Sizing air openingsSizing air openings for CGs installations Place boiler/crate near position 2a Prepare boiler placement & setupOrifice replacement procedure Inspect orifices and burnersDrain and remove fittings 2b Prepare boiler pressure testHydrostatic pressure test Prepare boiler for test3a Water piping general information 3b Water piping single-zone system Systems or converted gravity 3c Water piping multiple zonesPiping multiple zones Piping for radiant heating SystemsReturn water 130F or higher 3d Piping low temp systems Temperature gaugesValve adjustment Figures 8 and 9 only Primary/secondary preferred bypass piping methodPrimary/secondary piping Valve adjustment BOILER-bypass piping methodFigures 8 SYSTEM-bypass piping method 3e Water piping refrigeration systems Prevent chilled water from enteringVenting and combustion air Natural Gas Connecting gas supply piping to boilerGas piping Propane GasWiring connections Field wiringElectrical installation must comply with ThermostatCheck for gas leaks Freeze protection when used7a Start-up preparation Verify water chemistryFinal check before starting boiler 7b Start-up operate boilerInspect system water piping Inspect base insulation Start the boilerCheck for 7c Start-up if boiler doesn’t startCheck burner flames Pilot burner flame FigureCheck-out procedure checklist Installation and service certificate9a Operation sequence 9b Operation wiring diagrams Schematic wiring diagramLadder wiring diagram 9c Operating instructions CGs-3 to CGs-6 9c Operating instructions CGs-3 to CGs-6 9c Operating instructions CGs-3 to CGi-6 10a Service and maintenance schedule Verify Proper Operation After Servicing10b Service & maintenance annual start-up Inducer motor Burners, base and inlet air boxCondensate drain system Oiled-bearing circulators10b Service & maint. annual start-up Boiler relief valve Relief valve, typicalCleaning boiler heating surfaces Review with ownerCheck the following 11a Troubleshooting procedureBefore troubleshooting Check pressure switch setting 11b Troubleshooting air pressure switchAir pressure switch Troubleshooting air pressure readingControl indicator lights NON-LOCKOUT modes 11c Troubleshooting control moduleControl indicator lights Lockout modes Troubleshooting the control moduleControl module connections 11d Troubleshooting control module lights Chart 1 Troubleshooting Power light statusChart 2 Tstat Circ & Power lights flashing Chart 3 Press Switch & Power lights flashing Chart 4 Flame & Power lights flashing Item 8 , Does blower motor operate? Verify Sequence of operation, , 12a Replacement parts Section assembly Base Jacket Trim Controls12b Replacement parts section assembly Section assembly12c Replacement parts base Base assemblyDescription Weil-McLain Part number 12d Replacement parts jacket Jacket assemblyBoiler Model Weil-McLain part number 12e Replacement parts trim Part number12f Replacement parts controls Propane gas components13a Dimensions Dimensional drawing13b Ratings DOEHandling ceramic fiber and fiberglass materials Removal of Combustion Chamber Lining or Base Panels