Honeywell PDX75S70F(B,S,C)*(N,X) VAC Circuit Trace, PDX Series, Pdx Service Procedure

PDX Series

PDX SERVICE PROCEDURE IX

120 VAC Trace

120 VAC Circuit Trace

WARNING

120 volt potential exposure. Use caution

making voltage checks to avoid personal injury.

Step 1. Verify 120VAC and proper polarity at wall outlet.

Step 2. With unit plugged in and control power switch in the “ON” position verify LED status.

LED status	LED status
None, Control LED not	Short flash, once every
on or flashing.	four seconds.
	Waiting for
	call for heat.
	26
Disconnect cord set as
shown in photo 26

Using a volt meter set to volts AC, is there 120VAC N across terminals shown

in photo 27 ?

	Y
Is there 120VAC across		Y		Reconnect cord set
terminals shown in
				shown in photo 26.
photo 28 ?
	N
		Disconnect wire harness
Incorrect supply				from gas control
voltage polarity				(see photo 29).
Locate black & white wires at connector, It
may be necessary to pull back wire sheath
to identify wire colors.
(see photo 30)

Is there 120VAC across		Y	Replace gas
black & white wires as
			control.
shown in photo 30?
	N
Call for technical
support.

LED status	LED status
“Heartbeat”, alternates	Various flashing error
bright/dim.	codes.
Thermostat calling	Verify error code as
for heat	listed on page 12
27	28

Check for damage to AC Y		Repair damage
supply power cord.
	N
Replace Blower

29

Wire harness

30

Wire sheath pulled back to

identify wire colors

Check for 120VAC between black & white wires.

-NOTE-

Electronic meter probes required. Use care not to

damage connector during this check.

Page 30

30