nordyne furnace, propane, about year 2000
no circuit board, just relays and basic stuff
when i turn on the power, the combustion fan runs constantly. won't shut off.
this blows out the pilot light
This could be caused by a few things, does the thermostat keep the temperature, meaning regularly turn on and off? If so, you might have some wiring issues from the thermostat i.e, a short, or improper wiring to the furnace.