Weil-McLain 550-110-710/0107 manual How it works

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GOLD CGi 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 49).

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 boiler air openings. 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 the inducer is working correctly or the vent is blocked.

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:

asupply to system

breturn from system

cstainless steel burners

dflue outlet

egas valve

fpressure/temperature gauge

grelief valve

hair vent connection

iflame rollout thermal fuse element (TFE)

jburner shield

kpilot burner and bracket

lgas manifold

mcast iron boiler sections

nflue collector

ojunction box



Part Number 550-110-710/0107

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Contents Gold CGi How it works Gold CGi Gas-Fired Induced-Draft Water Boiler Contents Please 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 Chimney or vent require- ments When removing boiler from an existing common vent system1c Prepare boiler location vent system 1d Prepare boiler location air contamination Products to avoidAir opening options 1e Prepare boiler location air openingsAir openings must be provided Two openings Air supply from inside the buildingSingle air opening option Exhaust fans and air moversMotorized air dampers Exception for large spacesPlace 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 testCGi venting methods Chimney draft or Direct exhaust 3a Venting general informationVenting chimney draft venting Chimney draft venting3c Venting Direct exhaust components Obtain vent system components3d Venting direct exhaust vent starter Vent StaR-34 Vent starter3e Venting direct exhaust termination Vent termination minimum clearancesSidewall venting See Figures 14 3f Venting direct exhaust installationVertical venting See . Follow vent Using any termination other than one of those shown 4a Water piping general information Closed-type expansion tank 4b Water piping single-zone systemDiaphragm-type or bladder- type expansion tank Figure 4c Water piping multiple zones Piping multiple zonesZoning with circulators Valve adjustment 4d Piping low temperature systemsTemperature gauges Primary/secondary preferred bypass piping methodPrimary/secondary piping Valve adjustment BOILER-bypass piping methodBoiler-bypass piping Zoning with SYSTEM-bypass piping method 4e Water piping refrigeration system Prevent chilled water from entering boilerNatural 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 Determine if water treatment is neededInspect system water piping Do not use petroleum-based cleaning or sealing compoundsFill the system with water Inspect base insulationCheck system and boiler 7b Start-up operate boilerStart the boiler Check for 7c Start-up if boiler doesn’t startCheck burner flames Pilot burner flame FigureCheck-out procedure checklist Thermostats9a Operation sequence During main burner operation9b Operation wiring diagrams Schematic wiring diagramLadder wiring diagram 9c Operating instructions CGi-25 to CGi-6 9c Operating instructions CGi-25 to CGi-6 9c Operating instructions CGi-25 to CGi-8 10a Service and maintenance schedule Verify Proper Operation After Servicing10b Service and maintenance annual start-up Condensate drain system 10b Service & maintenance annual start-upBurners and base Inducer motorAir vents and air elimination Gas pipingCold fill and operating pressures Limit controls and cutoffsReview the User’s Information Manual with the owner Review with ownerBoiler relief valve Before troubleshooting 11a Troubleshooting procedure11b Troubleshooting components Air pressure switchControl indicator lights Lockout modes Control indicator lightsTroubleshooting the control module Control moduleControl module connections Remove 120 VAC in plug , Item 3, page 50 on control module 11c Troubleshooting control module lightsChart Light flashing VAC in plugChart 2 Tstat Circ & Power lights flashing Chart 3 Press Switch & Power lights flashing Chart 4 Flame & Power lights flashing Usually indicates flame sensed when it shouldnt be thereDoes blower motor operate? Item 8 , Verify Sequence Operation, FigureControls Repair Parts Lists 12a Replacement partsSection assembly Base Jacket Trim Controls 12b 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 BoilerModel Weil-McLain part number 12e Replacement parts trim Fittings shown are included with boiler12f Replacement parts controls Propane gas components13a Dimensions Dimensional drawing13b Ratings Handling ceramic fiber and fiberglass materials Removal of Combustion Chamber Lining or Base Panels