Anyone good with the HVAC?

Missourian

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Aug 30, 2008
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I have a no heat condition on an electric furnace

I've jumpered the thermostat.

Red to white... which should activate the heat coils immediately turns the fan on with no heat.

Any ideas?
 
I have a no heat condition on an electric furnace

I've jumpered the thermostat.

Red to white... which should activate the heat coils immediately turns the fan on with no heat.

Any ideas?
Do you have a diagnostic system on it? If you don't know, find the model and download the User Manual it may give you different blinking coloured lights etc. to make you aware of a particular problem. You can then resesrch a solution online to said problem.
 
See if you can find a schematic, should be on the inside of the cover where the fan is.
Screenshot_20230218-155844-008.png
 
Do you have a diagnostic system on it? If you don't know, find the model and download the User Manual it may give you different blinking coloured lights etc. to make you aware of a particular problem. You can then resesrch a solution online to said problem.
This one isn't that high speed.

Have to manually check voltages and continuity.
 
Oh I see, thermostat problem, nm. I've dealt wth those before, was so deperate one year in the winter I just set the wiring to have heat only but we didn't have A/C that summer. Same problem, fan only beforehand no heat. Eventually I went back at it. The location of thermostat and wire length ensures it is an inconvenient pain. Sometimes it is a ground wire off connection or even a wire touching two different screws etc. Or, as in my case, the bloody wires were a different color from the provided legend.
 
If that is for your unit the heating element is cropped off the image. It looks like it is in the missing section on top of this image.
 
If that is for your unit the heating element is cropped off the image. It looks like it is in the missing section on top of this image.
Here's the link...

 
Are the coils corroded? The coils themselves could be bad.

Burned out coils
I'm leaning that way...but to visually inspect them I must pull the internal circuit breakers... Which means no more testing.

I'm slowly working thru the relay testing and continuity testing.

The white 27v wire shouldn't activate the fan.

I'm hoping someone had seen this before.
 
if that's the sch for your unit look for 24vac on terminals 4 and 6 (blue and white) in the 9 pin connector to the elements. The relay is probably a black plastic box near the elements. They could be burned out or the temp limit could be bad. Don't confuse the 240 volt wiring for the 24 volt control wires unless you are comfortable with that. There should be a 7 second time delay from when the fan starts to power the strip heaters, if not the blower time delay relay may be bad.
 
I have a no heat condition on an electric furnace
I've jumpered the thermostat.
Red to white... which should activate the heat coils immediately turns the fan on with no heat.
Any ideas?

Do you have a multimeter? Sounds like you have an open somewhere in the heating element circuit, possibly the element itself, a connection or a solenoid. I would run a continuity test.
 
if that's the sch for your unit look for 24vac on terminals 4 and 6 (blue and white) in the 9 pin connector to the elements. The relay is probably a black plastic box near the elements. They could be burned out or the temp limit could be bad. Don't confuse the 240 volt wiring for the 24 volt control wires unless you are comfortable with that. There should be a 7 second time delay from when the fan starts to power the strip heaters, if not the blower time delay relay may be bad.
I'll time the delay.

Relay makes sense...that is a location the fan and heat would intersect.

I'll check it out...thanks.

Might be awhile getting back...phone has to charge.
 

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