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knapp302
Oct 11, 2007, 08:01 PM
Hi,
I have a Williamson "Temp-o-matic" forced air oil furnace. I just recently purchased the house and when I went to change the thermostat it only had two wires wired to it (just a 2 conductor wire with no other wiring). When I connect those two wires together, the furnace comes on and generates heat. I noticed that the blower motor never came on to push heat in to the house.
During further inspection, I found a standard style light switch on the side of the furnace that would turn the blower on and off at any given time. There are no unattached wires anywhere near the furnace.

I ran a new 6 conductor wire to the furnace when I replaced the thermostat, but I don't know what to do to get the blower to come on automatically?

Thanks in advance,
Marty
:cool:

hvac1000
Oct 11, 2007, 11:25 PM
You may have a defective fan and limit control. Williamson oil equiptment use this style to control the blower and also to shut the burner off if the temp went to high as in when the blower does not work. It is usually a honeywell control mounted on the upper face of the furnace above the burner. You can test this control if you have a meter. Also this control sometimes has a white push pull control to allow manual operation of the blower or automatic. If you look in the sticky notes at the beginning of this section there might be some info there for you to read about this control.