Gas-Fired Products 40, N7/L7, 100, 150, 175, 200 manual 22.0, Troubleshooting Guide

Form #43343530 July 08

Turn on line voltage	Does the blower
and adjust thermostat	come on?
to the highest setting.	No
Does the red
monitoring light come
on?

Does the LED on the	Is the black tap on the	Check the probes and	Replace air switch.
ignition module flash	air switch connected	hoses to the air switch
Yes once?	Yes to the upper probe? Yes	are they clear and	Yes
		unobstructed?

22.0)

–43–

No
Is 120V at the terminal		Check line voltage
block in the blower?	No	circuit. Repair fault.
Yes
Is there 120V		Check terminals for
between ground and		continuity and repair.
the L1 terminal on the	No
module?
Yes
During start up, is
there 120V between
ground and the IND
terminal on the
module?
Yes
Disconnect the power		Remove any
and check the blower		obstructions. Repeat
wheel. Does it turn	No	start up. If motor will
freely?		not run. replace
		motor.
Yes
Replace motor.

No		No
Check NO terminal of		Switch hoses on the
the air switch		pressure taps.
connection. Replace
red light.
		Check terminals for
		continuity at
		transformer. If they
		are good, replace
		transformer.
		No
Is the LED on the		Is there 24V between
ignition module		the inlet to the fuse	Yes
No steady ON?	No	carrier and the
		ground?
Yes
Replace ignition		Check that red wire is
module.		connected to TH from
		air switch terminal C.	No
		Repair connection.
		Remove jumper, air
		switch must be open
		circuit first for blower
		to operate.

No

Clean out hoses and probes.

if fuse carrier is tight and the fuse has no continuity, replace the fuse.

No
Is there 24V on the		Is there 24V between
other side of the fuse	Yes	both terminals of the
carrier?		TISS and ground?
		Yes
Is 120V at the terminal		Is there 24V between
block in the blower?		both terminals of the
	Yes thermostat connection
		and ground?
Yes		No
Replace ignition		Does the system have
modules.		a 24V individual
		thermostat?

No

No

Check TISS wire for a break if it is close to the terminal repair.

Otherwise replace TISS wire.

No
The TISS has broken	Replace heat
continuity. Check the	exchanger tube,
first tube and reflectorYes	reflector and TISS.
is there a hole?

Repair or replace jumper check all wire terminals.

TROUBLESHOOTING GUIDE

Yes
Does the blower stay	Is the knob on the gas
on?	valve turned to the
	No ON position?	Yes

No

Turn on the gas valve?

				Yes	Yes
Does the LED on the		Is the orange wire		Are air switch	Repair or replace
ignition module flash		from PSW connected		terminals jumpered?	thermostat. Check
once?	No	to the NO terminal of	Yes		external wiring.
		the air switch?
Yes		No		No
Move black light wire		Move orange wire to		Air switch is stuck in
to NO terminal of the		NO terminal. Restart		the closed position.
air switch. Restart the		troubleshooting.		Replace air switch.
troubleshooting.

Yes
Does the low fire	Is the LED on the		After 15 seconds		Are the blue wires		Are the black wires	Replace amber light.
amber light come on?	ignition module		post purge is there		secure in the		to the amber light	Restart
No	steady ON?	No	24V between V1 and	Yes	terminals and firmly	Yes	securely on the gas	Yes troubleshooting.
			V2 ignition module		on the ignition		valve terminals?
			terminals?		module terminals?
	Yes		No		No		No
	Replace ignition		Replace ignition		Repair connection.		Repair connection.
	module.		module.		Restart		Restart
					troubleshooting.		troubleshooting.
Yes
Troubleshooting
continued on the next
page.