7800 SERIES RELAY MODULES
b.On the subbase, jumper L1 to the ignition terminal; refer to the appropriate wiring diagram to determine the proper terminal. Disconnect the leadwire to the pilot valve if it is connected to the same terminal.
c.Close the master switch to energize only the ignition transformer.
d.If the ignition spark is not strong and continuous, open the master switch and adjust the ignition electrode spark gap setting to the manufacturer recommendation.
e.Make sure the ignition electrodes are clean.
f.Close the master switch and observe the spark.
g.After a continuous spark is obtained, open the master switch and add a jumper on the subbase from terminal L1 power to the pilot terminal 8 or 21. Reconnect the leadwire from the pilot valve if it was disconnected in step b.
h.Close the master switch to energize both the ignition transformer and the pilot valve.
i.If the pilot does not ignite and if the ignition spark is still continuous, adjust the pressure regulator until a pilot is established.
j.When the pilot ignites properly and stays ignited, open the master switch and remove the jumper(s) from the terminals of the subbase.
k.Check for adequate bleeding of the fuel line.
l.Reinstall the 7800 Series Relay Module on the subbase, close the master switch, and then return to step 4.
7.When pilot ignites, measure the flame signal. If the pilot flame signal is unsteady or approaching the 1.25 Vdc minimum value, adjust the pilot flame size or detector sighting to provide a maximum and steady flame signal.
8.Recycle the system to recheck lightoff and pilot flame signal.
9.When the MAIN LED turns on, make sure the automatic main fuel valve is open; then smoothly open the manual main fuel shutoff valve(s) and watch for main burner flame ignition. When the main burner flame is established, go to step 16.
10.If the main burner flame is not established within five seconds or the normal lightoff time as specified by the equipment manufacturer, close the manual main fuel shutoff valve(s).
11.Recycle the system to recheck the lightoff and pilot flame signal.
12.Smoothly open the manual fuel shutoff valve(s) and try lightoff again. (The first
13.If the main burner flame is not established within five seconds or the normal lightoff time specified by the equipment manufacturer, close the manual main fuel shutoff valves(s). Check all burner adjustments.
14.If the main burner flame is not established after two attempts:
A.Check for improper pilot size.
B.Check for excess combustion air at low fire.
C.Check for adequate low fire fuel flow.
D.Check for proper gas supply pressure.
E.Check for proper valve operation.
F.Check for proper pilot flame positioning.
15.Repeat steps 8 and 9 to establish the main burner flame; then go to step 16.
16.With the sequence in RUN, make burner adjustments for flame stability and Btu input rating.
17.Shut down the system by opening the burner switch or by lowering the setpoint of the operating controller. Make sure the main flame goes out. There may be a delay due to gas trapped between the valve(s) and burner. Make sure all automatic fuel valve(s) close.
18.Restart the system by closing the burner switch and/or raising the setpoint of the operating controller. Observe that the pilot is established during PILOT IGN and the main burner flame is established during MAIN IGN within the normal lightoff time.
19.Measure the flame signal. Continue to check for the proper signal through the RUN period. Check the signal at both High and Low Firing Rate positions and while modulating, if applicable.
20.Run the burner through another sequence, observing the flame signal for:
a.Pilot flame alone.
b.Pilot and main flame together.
c.Main flame alone (unless monitoring an intermittent pilot). Also observe the time it takes to light the main flame. Ignition of main flame should be smooth.
21.Make sure all readings are in the required ranges before proceeding.
22.Return the system to normal operation.
NOTE: After completing these tests, open the master switch and remove all test jumpers from the subbase terminals, limits/controls or switches.
Direct Spark Ignition Systems
This check applies to gas and oil burners not using a pilot. It should immediately follow the preliminary inspection. Refer to the appropriate sample block diagram of field wiring for the ignition transformer and fuel valve(s) hookup.
NOTE: Low fuel pressure limits, if used, could be open. If so,
bypass them with jumpers during this check.
1.Open the master switch.
2.Complete the normal
3.Close all manual main fuel shutoff valve(s). Check that the automatic fuel valve(s) is closed. Make sure fuel is not entering the combustion chamber.
4.Close the master switch and start the system with a call for heat by raising the setpoint of the operating controller; see the relay module sequencing. The program sequence should start the INITIATE sequence.
5.Let the sequence advance through PREPURGE (if applicable). Ignition spark should occur when the PILOT LED turns on. Listen for the click of the first stage fuel solenoid valve(s). The relay module locks out and the ALARM LED turns on.
6.Let the 7800 Series Relay Module complete its cycle.
7.Open the manual fuel shutoff valve(s).
8.Push the reset button and the relay module recycles the program sequence through PREPURGE (if applicable).
9.When the PILOT LED turns on, make sure that the first stage burner flame is established. If it is, go to step 15.
10.If the first stage burner flame is not established within four seconds, or within the normal lightoff time specified by the equipment manufacturer, close the manual fuel shutoff valve(s), and open the master switch.
11.Check all burner adjustments.
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