Furnace problem, Real technical.

[Navigator]

I know that the circuit board in my Suburban NT-30SP is bad because it will not open the gas line solenoid, even though the sail switch, limit switch, and the time delay relay all combine to send 12v to the circuit board. In addition,
THERE IS NO (BURNER FLAME) SENSOR PROBE INSTALLED IN THIS FURNACE!!????? and no provision for one?? Am I missing something here?
Dick

[thenewkid64]

Navigator,

You are saying if you pull the metal pate on the left side of the burner assembly there is only 1 probe? Only 1 wire for the igniter?

The flame sensor could have broken off and fallen into the furnace.

[Navigator]

That is correct. Only 1 wire, that wire is the igniter.
There is no provision in the plate that supports the igniter and burner for a wire going into monitor the flame!!
Inside the above mentioned plate there is NO provision for a sensor. Only the spark rod and the ground rod. I am confused.
Dick

[thenewkid64]

I thought mine had 2 wires, but I may be wrong. I just had to replace the board in mine or the same reason. While I had it out I did the sail switch too.

[thenewkid64]

Are you sure it is an NT-30SP? I need to check my manuals and see if it references a model without a flame sensor.

Here is a lintk to an old manual

[markdoane]

Link to Suburban furnaces: Suburban

[Navigator]

Brett,
Positive: NT-30SP
I downloaded a Suburban Dynatrail Furnace Manual.
Get this!
There is a discrepancy between the wiring diagram glued onto the furnace, and the wiring diagram in the Service Manual for the NT30-SP!!
My unit wiring diagram does NOT show a sensor!!
I think that I need to call the factory.
Dick

[Navigator]

Additionally: The label glued onto my unit says NT34!!! and thats the way its wired.
while the name plate says NT30SP.!!!
I need a drink.
Dick