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GB300 BOILER INSTALLATION AND OPERATION INSTRUCTIONS
6.Remove the front grill(s).
7.Connect a manometer having a minimum capacity of 20" WC to the outlet pressure port of the gas valve. Make sure that the gas supply piping has been purged of air and that all gas joints up to the gas valve have been thoroughly checked for leaks.
To Turn Off Gas To Boiler
1.Set the operating control to its lowest setting.
2.Turn off all electric power to the appliance if service is to be performed.
3.Close the manual main and pilot gas
8.Open the petcock pilot valve.
9.Turn on all electric power to the boiler.
10.Set the operating control to the desired setting.
11.The pilot(s) should automatically light. Do not try to light the pilot(s) by hand!
12.With the pilot(s) lit, open the main gas
13.The burners should light with proper boiler operation.
14.A boiler designed for use with natural gas should have a manifold gas pressure of approximately 3.5" WC on high fire and 0.8" WC on low fire. For an LP boiler, the manifold pressure should be 10" WC. To adjust the manifold gas pressure see the GAS PRESSURE ADJUSTMENT instructions in the BOILER CHECKING AND ADJUSTMENT section.
15.With the burners in operation, close the manual shutoff valve in the gas supply line. As soon as the main burner flames go out, open the manual shutoff valve. A normal ignition sequence should take place. If the burners fail to light the system will make two more ignition attempts. If the burners have not lit after the last ignition try, the gas valve will close and the system will go into lock out. DO NOT attempt to reset the system until the ignition system has been inspected and the problem resolved.
With the burners in operation, interrupt the power to the control circuit by lowering the operating control.The main burners should go out. Reset the operating control, a normal ignition sequence should follow.
To test the ignition safety shutoff device, close the manual shutoff valve in the gas supply line. Within 6 seconds of main burner flame extinction, the main gas valve solenoid should close with an audible noise.
A sparking noise should be heard while the ignition module tries to light the pilot. After 1 minute the module should lockout and the try for ignition end. Open the manual shutoff valve in the gas supply line and reset the ignition control system. A normal ignition sequence should take place.
BOILER CHECKING & ADJUSTMENT PILOT ADJUSTMENT
The pilot burner flame should envelope 3/8" to 1/2" of the thermocouple tip or
1.Remove the cap next to the pilot tube fitting on the gas valve or on the separate pilot gas regulator where one is used.
2.Turn the pilot adjustment screw on the valve counterclockwise to increase the flame, clockwise to decrease it. On the separate pilot gas regulator turn the regulator screw clockwise to increase the flame, counterclockwise to decrease it.
3.Replace the pilot adjustment screw cap.
Figure 103 | Pilot Flame Adjustment |
SCREWS
BRASS FERULE
1/4" TUBING
Gas Pressure Adjustment
NATURAL GAS: Optimum results are obtained when the boiler is operated at its full input rating, with 3.3" WC to 3.7" WC and 1.0" to 0.8" on low fire of manifold pressure.The manifold pressure should not vary outside this range. The gas valve pressure regulator has been preset at the factory. If adjustment is necessary the following steps must be followed:
NOTE: The Honeywell VR8404 valve is factory set and cannot be field adjusted
