Furnace Igniter

by Dean Benoy

Feb 2

I have a 1978 class c motorhome that we are doing some restoration on.

Last fall we tried to start the furnace but to no avail. Mud-daubers had built a nest in the fan along with a mouse nest so the fan would not turn The furnace is a Suburban ST30 SP. Everything appears to be fairly new so I am quite sure it has been replaced in the not to distant past. I wanted to test the electronics before I reinstalled it. WIth 12 volts to it and the thermostat wires jumpered the fan turns on, the sail switch works, i get 12 volts across the gas switch and can hear the solenoid engage. I am also getting 12 volts to both sides of the thermal switch. However, I don't seem to be getting any power/spark at the igniter. 

Can anyone tell me if there is a way to test the igniter or determine if it could be a control board problem?

  • up

    Jimco_W001

    Hi Dean. Have you checked how well the igniter is grounded?

    Feb 4

    • up

      Dean Benoy

      Thank you Jimco

      You are right on the money.

      I worked on it again last night and that appears to have been the problem.

      I am als used to a more robust spark and actually hearing the spark as with my other furnaces in my shop.

      The spark in the RV furnace is very subtle.

      Feb 4