Continous Fan Intertherm e3eb-015H

[mceach]

I just purchased my new home which has a Intertherm central heater - model E3EB-015H and I can't make the fan only come on. I looked in the wiring in the heater and the thermostat is connected but there is a gray wire from the furnace not connected to anything. Is that the wire that should be attached to one of the thermostat wires? Any help appreciated.....Rich

[Robert]

Hi Rich,


The green wire from t-stat is wire for that, where is it connected ?


Do you have a/c also ?




Thanks,
Robert

[mceach]

Thx...the green wire from the t-stat is connected to the green wire in the furnace...I don't have air. The red wire to the red....and the white wire to the white and the yellow and blue are not attached in the furnace...

[Robert]

Does your t-stat have a C for a common wire connection ?

That Grey wire is the common wire for the operation of that .



Thanks,
Robert

[mceach]

Thx Robert - I figured it out yesterday. I had to jump the Rh and Rc wires in the tStat.

[Robert]

Hi,

You're very welcome. After looking at diagram again, the grey common goes to blower relay before t-stat, so wouldn't be needed for what you wanted.


In continous fan ON, the blower runs in high speed same as in cooling mode and is operated by the blower relay.


The relay coil has the grey common, but needed the green power wire for it to energize.


With only one transformer, RH and RC need to be jumpered to run both modes.


You don't have a/c, but needed that mode to run blower on continous.


Jumping RH (power heat) to RC (power cool) did that.


Glad you got it, been very busy with Mark on mini vacation.



Thanks,
Robert