Utica Boilers MGB Series II/MGC Series 安装指导

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STEP 3: Check spark ignition circuit. 
Disconnect ignition cable at SPARK terminal on module.

Electrical shock hazard. Ignition circuit generates 

over 10,000 volts. Turn OFF electrical power 

supply at service panel before making electrical  

connections.  Failure to do so could result in death 

or serious injury.

  

Energize module and listen for audible sparking noise. 

When operating normally, there should be a buzzing noise 

that turns on and off twice per second for duration of 1–7 

seconds depending on model.
STEP 4: Verify pilot and main burner lightoff.

• Initiate call for heat. Turn thermostat above room 

temperature.  Ignition sequence may be delayed by 

thermal purge until boiler water temperature is below 

140°F (60°C)

• Watch pilot burner during ignition sequence.  

— Verify ignition spark continues after pilot is lit.
— Verify pilot lights and spark stops, verify main  

burner does not light.

• If so, ensure adequate flame current as follows.

— Turn off boiler at circuit breaker or fuse box.
— Clean flame rod with emery cloth.
— Verify electrical connections are clean and tight. 

Replace damaged wire..

— Check for cracked ceramic insulator, which can 

cause short to ground, and replace igniter-sensor if 

necessary.

— At gas valve, disconnect main valve wire from MV 

terminal.

— Turn on power and set thermostat to call for heat. Pilot 

should light, main burner will remain off because main 

valve actuator is disconnected.

— Check pilot flame. Verify it is blue, steady and 

envelops 3/8 to 1/2 in. [10 to 13 mm] of flame rod. 

See Figure 24 for possible flame problems and causes. 

— If necessary, adjust pilot flame by turning pilot 

adjustment screw on gas control clockwise to decrease 

or counterclockwise to increase pilot flame. Following 

adjustment, always replace pilot adjustment cover 

screw and tighten firmly to assure proper gas control 

operation. Figure 16, page 19. 

— Set temperature below room set-point to end call for 

heat.

• Recheck ignition sequence as follows.

— Reconnect main valve wire.
— Adjust thermostat above room temperature.
— Verify ignition sequence at burner.
— If spark does not stop after pilot lights, replace 

module.

— If main burner does not light or if main burner lights 

and system locks out, check module, ground wire and 

gas control as described in troubleshooting table. See 

Table 6, Page 24.