Intertherm E2EB-017HB - Heating Element Stays On

[Auger1981]

Having more problems with my Intertherm E2EB-017HB furnace.

Last summer as some may remember, I had issues with my cooling coil. Condensation ran all over the components. Since that time I have had the coil replaced. This fall when I started my furnace everything seemed to work fine. However, if I turned thermo past 72, I would start to hear some chattering in the furnace. I opened the cover to see the contactors opening & closing. (You could see the flashing). Since I had water on the components I decided to replace both contactors & the breakers. (Duel breaker setup).

Everything seemed to work fine... at least for a couple weeks. Friday I came home and smelled something hot. I checked the thermostat and house was at temp, so the furnace was off. However when I got close to it, I could feel the heat radiating off it. Further inspection found the heating element still on. Here is where is gets interesting.

The only components I can see that I hadn't replced were the transformer & what are called the blower relays. I replaced the relays today, and still the same problem with both the heating element not turning off and the chattering relays after a bit of running. I will be replacing the transformer tomorrow.

Each time I discuss this furnace with people, they talk about the sequencer. I know what they are, and what different ones look like. I have however, never found anything that remotely looks like that in my furnace. Is it possible that this one does not have one ?? My parts breakdown doesn't list any sequencer. (The parts listing is from Nordyne).

I have checked all my connections against the wiring schematics I have, as well as the original photos I took before I ever took a single wire off this thing. All appears to be fine.

Sorry this was so long, any feedback would be appreciated.

 

[Auger1981]

OK, it would appear that I have temporarily fixed this unit... at least the part where the element stays on. I checked the 2 coils & found one had fallen off its standoff. I fixed it and they no longer come on with the thermostat off & the main breakers on.

I still have an issue with the contactor(s). After the furnace has run for a little while, I hear a intermitten snapping from the contactor(s). I have replaced the following items in this thing:
Both Contactors
Transformer
Both Breakers
Both Fan Controllers
There isn't a whole lot left in this thing. All connections appear to be clean & well attached to each component. (ie. no loose wires/connectors).

I can not imagine that the limiter switch(s) would cause this, but those are all thats left without replacing both heating elements. I'm guessing that if a limiter went out, it would shut off the furnace, not make the contact chatter. BUt at this point, I'm about to go buy a sledge hammer. Tried to contact Nordyne, but they won't assist.

Please please please help !!

 

[Sponsor]

 

[DonL]

It sounds like a Contact may be welding together, Because of Pitted contacts in the contactor. It gets stuck ON. Being they are new not sure, unless a bad shorted element.

The limit switch should shut it down, But it should not be the cause of your problem.

If the element was touching ground, because of a standoff, then it should have had 120V across the element, and twice the Current or more, depending on where it was shorted.

Many contactors have a Red popup button that lets you see if it is open or closed. If it shows closed and there is no voltage on the coil, then the contacts are stuck.

If the element was on with no airflow, then it may be toasted.


Good Luck.

 

[Auger1981]

No red popup button on these. Yes they are brand new, and rechecked them (removed the cover over the contacts).

The elements were lighting up even with the thermostat off and the contactors open. In anycase, after I took out the elements, fixed the standoff and replaced them, the system appears to be functioning. I still hear the occasional contactor click. The elements now turn off when the thermostat shuts the furnace down.

Could a bad element possibly cause this clicking ?? It's not constant, and not on every heat cycle. Seems to be more often if the temp needs to be boosted more then 1 or 2 degrees.

Thank again, really appreciate your assistance !!

 

[DonL]

What is your thermostat model ?

Is it a smart one ?

Some t-stats that try to anticipate may cycle the elements on and off.

Do not know what is making the clicking sound ?


Good Luck.

 

[Auger1981]

The clicking is the contactor. Its fast open then closed. But not everytime, and not consistant. I have had the front open to watch and you can see the flash from the contactor. I have a feeling that the elements have been my issue from the very beginning.

I replaced the thermostat a few years ago. Went from the old mercury bulb to a digital. Not sure its considered a smart one though... made by Hunter. Going to have to do a little digging to get you the model.

**edit** Clicking happened before thermostat change out. My wife had to remind me...lol. We have gone through at least 2 if not 3 sets of contactors.

 

[DonL]

It could be that you have a big voltage drop and the contactors can not hold in under the load.

A loose connection at the breaker may cause that.


You may want to look at the voltage drop at the unit when it calls for heat.

 

[Auger1981]

Breakers were replaced new. Connections there are sound.

Could an element cause all this ??

 

[Reach4]

Can you watch the volts (VAC across) the coil wires/terminals?

 

[Auger1981]

I am so sorry for the delay in getting back to all of you. My heating/cooling supply company took is time getting me the elements. So here is the latest & greatest:

I replaced the heating elements and now everything appears to be fine. Good heat, and no contactor chattering.

I inspected the elements closer, the lower element had a ceramic stand off that had broken. That coil was touching the metal frame that supports it. However, since the element was so old, and had water fall on if during the summer, it had rusted. Therefore the element wasn't shorting out completely. I would have read the voltage as Reach4 suggested, but I had managed to temporarily fix the standoff, and didn't want to mess with it until I got the new elements in from supply.

It would appear that the majority of my problems had been caused by the element. Now with 2 new ones in plave, I have a furnace that is working as expected, and I can now get a good nights sleep. I want to thank you all for your input & support. I will now dissapear until it's time to turn on the AC...lol

Have a great day !!

 

[DonL]

Thanks for the report, that is great news.

Glad you were able to make it work.


Enjoy.