All of a sudden I noticed my heat was running non stop. So I went to the thermostat and clicked it to the off position, it went off. I decided to see if the air was doing the same. Sure enough flip it over to air the air will run constantly. In both cases it was not just the fan running, the heat heated and the air cooled. In fact if you flip the system from auto to fan it goes off and nothing runs.

I thought I would try replacing the thermostat first. So armed with a new one I replaced everything, re-stripped wires in case one was broken. Hooked everything back up, flipped the switch to heat and again it would not shut off, same with the air. Again I flipped the switch from auto to fan and it goes off. :confused:

Today I went and bought a new relay and thought that would for sure fix it. It didn't work same issue's. I even unhooked the red and white coming from the outdoor unit and nothing has changed except for the air not kicking on now. I'm really at a loss as to what it can be. Any help would be greatly appreciated.

Furnace information:
Miller E3EB-015H, 017H

Is this a electric or gas furnace?

Is this a electric or gas furnace?

I'm sorry it's all electric

Then it sounds to me like you have a bad heat senqucer

http://www.drillspot.com/pimages/63/6339_300.jpg

When they get hot and stop working the heat will stay on on the heating and the ac mode. Intill the breaker is shut off usually

then it sounds to me like you have a bad heat senqucer

Would it also cause the air to kick on and say on?

when they get hot and stop working the heat will stay on on the heating and the ac mode. intill the breaker is shut off usually

Ok so when the switch is flipped to air it would cause the outdoor unit and compressor to kick on?

This actually brings on the heat and the fan

When you have the ac on is it as cold as it is supposed to be? Odds are the heat is running with the ac

when you have the ac on is it as cold as it is suposed to be? odds are the heat is running with the ac

Oh yea very cold.

No the compressor should only run if the ac is turned down and calling for cooling? Is this a heatpump or strait electric furnace?

no the compressor should only run if the ac is turned down and calling for cooling? is this a heatpump or strait electic furnace?

Electric furnace with an outdoor air unit. You can definitely hear the outdoor fan and compressor kick on and the air is cold.

Is this a newer unit? If so you may not have heat sequencers, but a control board instead.

The relays in the control board may be going bad.

The relays in the control board may be going bad.

The picture you posted, it has two of those lines up vertically.

Do you notic any burnt or lose wires on them? Make sure to turn the power off before looking

do you notic any burnt or lose wires on them? make sure to turn the power off befor looking

I will look. I dabble in all kinds of things. The power is the first thing I do.:D

I was looking at a diagram of your unit. Up on the blower do you have a control box there?

i was looking at a diagram of your unit. up on the blower do you have a control box there?

No all I see is the back part of the blower. It has a bundle of wires coming from the blower to a plug-in. That is all there is coming from the blower. I will see if I can get a picture uploaded.

OK, still trying to find a good wiring diagram

ok, still tring to find a good wiring diagram

http://i42.tinypic.com/vh9v1d.jpg

That's the diagram.

Are both of you heat sequencers double stacked like the pic I sent or is one just a single?

are both of you heat sequencers double stacked like the pic i sent or is one just a single?

Double one on top of the other.

are both of you heat sequencers double stacked like the pic i sent or is one just a single?

Here is a picture of them

http://i41.tinypic.com/j9c3t5.jpg

I am about 85% sure the one on the top is your problem, but with out being there is very hard with electric furnaces. Turn the power back on. Turn the heat up. Then turn it down. If it continues to run. Then find something that will not conduct electricity, a small piece of wood, a plactic pipe. What ever and give it a few taps and see if it goes off. Or we can test for voltage. Do you have a volt meter?

i am about 85% sure the one on the top is your problem, but with out being there is very hard with electric furnaces. turn the power back on. turn the heat up. then turn it down. if it continues to run. then find something that will not conduct electricity, a small piece of wood, a plactic pipe. what ever and give it a few taps and see if it goes off. or we can test for voltage. do you have a volt meter?

Yes I have one.

i am about 85% sure the one on the top is your problem, but with out being there is very hard with electric furnaces. turn the power back on. turn the heat up. then turn it down. if it continues to run. then find something that will not conduct electricity, a small piece of wood, a plactic pipe. what ever and give it a few taps and see if it goes off. or we can test for voltage. do you have a volt meter?

Keep in mind if I kick it over to air the outside unit will come on and stay on no matter what temp I put the thermostat on.

OK when the unit is calling for heat you will have power on both sides of the sequencer. When the call for heat stops the sencer should cool down and the power should not be going threw. Check from a ground to the right side of the senq first

You have no other relays in your unit but the two you just sent me a pic of?

I also tapped the sequencer with a rubber mallet and it continued to run.

you have no other relays in your unit but the two you just sent me a pic of?

Just the relay that the thermostat wires are connected into. I replaced it though.

It's the top little one.

http://i41.tinypic.com/bgtd9y.jpg

Well if you changed the t-stat, and that relay. Then the 2 sequencers are all that is left. Its hard to tell from your picture. Are they the same?

well if you changed the t-stat, and that relay. then the 2 sequencers are all that is left. Its hard to tell from your picture. are they the exact same?

No. The top one is bigger and has more leads. The bottom one is about half the size.

OK the top one then is the one we need to worry about. It contols the heat, the fan for heat, and the fan for ac. The botom is just for the second heat strip.

ok the top one then is the one we need to worry about. it contols the heat, the fan for heat, and the fan for ac. the botom is just for the second heat strip.

Ok so I should probably replace it and see what happens?

That would be my best bet. Like I said I am about 85-90% that's your problem. But with so many wires on a elactric furnace with out me being there is hard to be 100%

Also, if you check back on here later there are a lot of people that will comment. Maybe someone will agree. Or has a better thought on what to try.

also, if you check back on here later there are alot of people that will comment. maybe someone will agree. or has a better thought on what to try.


Ok also the top one has a copper coil under it. Doesn't look like any sequencer I have ever seen. I took some numbers off it and googled them and got nothing.

3100-20Q552c
Coil 24VAC

Sounds like the top one may be just a contactor then.