EB17B blowing cold air occasionally

[ClevelandRocks]

I have a modular home with a EB17B electric furnace. It's OCCASIONALLY blowing cold air, so naturally, the fan runs but it never reaches thermostat setting. Last nite it happened agan. All I did was power everything down, then back up, and it worked. Obviously something is failing and I don't wanna wait till it completely quits. I've read many of these posts. Seems like #3115-3571 sequencer is high failure item. Does it sound like it's the probable cause here also? Thanx in advance!

[Robert]

Hi,

It's a good possibility. It's not so much a high failure item as it is the fact that it's a switch with 3 sets of contacts that open and close several times each cycle.


Eventually they ALL have a weak set of contacts quit working.


The furnaces that sequencer fits are the most commonly bought, so it appears as a high failure item.



Same can be said and found about contactors for outside a/c condensers.



When it does that, you can test the ends of each element to see if each is receiving 240VAC.


If not, sequencer is most common reason, but could be a bad limit also.



Thanks,
Robert

[ClevelandRocks]

First of all, THANX MUCH for replying and maintaining this website. The info I picked up here has been INVALUABLE in solving the problem. Luckily, the problem occurred again last nite and I had my VOM ready. I had no power to the low heater and started back-tracking. Had nothing coming in/out on the red wire to/from sequencer. Went back to the SPDT brk and found one side burned open. This was really strange, I don't believe I've ever seen a breaker burn open then reset itself without bein touched. I even wrung it out after removing it, and sure nuff, one side open. Anyway, thanx again, a serviceman would have never found this unless it occurred while he was here. Naturally if it was working, everything would have read correctly and he'd have probably replaced the sequencer as a probable cause.

[Robert]

You're very welcome, happy to help. What the service Tech would have done depends on the Tech, LOL.


I would not replace anything IF all worked and read correctly when tested.


However, because you said it would quit, I would know it was intermittant, wired in some "tattle-tales" to leave behind.


Whenever it did this agin, the tattle-tale wired in with THAT breaker would have blown a fuse letting me know on return, what was bad.


Glad it is ok now.



Take care and best wishes,
Robert