Heating elements won't turn off.

[Louie]

I have a coleman evcon furnace in a mobile home and i noticed the fan was not running and the heating elements would not turn off, i had to switch off the breaker to the furnace to make the elements turn off.
What could the problem be?

Brand "Coleman"

Model Number
3500A812

Volts/HZ/Phase
240vac/60/1

Element KW/Amps
11.2/46.7

Sincerely
Louie

[Robert]

Hi Louie,

Most likely a bad sequencer.


Sequencer # 3110-3571 @ $24.41 + $6.75 shipping .


It can be seen and ordered through PayPal from left side here :

http://www.mobilehomerepair.com/ColemanElec.html



Or, by calling toll free after 9 AM CST to 1-877-263-7860

and charging to Visa or Mastercard.


Let me know if ordering from outside the U.S. for added info.



Thanks for inquiring,
Robert

[Louie]

Robert,

Thanks for the quick reply.
So you think it's a bad Sequencer and not a bad limit switch,or does my model not have limit switches.
I would like to order the part if that is what you suggest is the problem.
Unfortunately i will not be ordering through paypal do to bad past experience of having my account hacked.
If i order by phone call can you tell me about how long it will take to get my order. It's supposed to get cold the next few days here on the east coast.

Louie

[Louie]

Robert,

After more reading i noticed that the heating elements do have limit switches.
So let me describe the problem i am having.
When i came home from work yesterday i noticed it was extremely hot inside and the t-stat said it was 85 degrees, it is set at 70 degrees.
I went to check the furnace and the cover was so hot you could barely touch it.
So i took the cover off and the fan was not running but could still see the elements glowing.
Does this also mean i have bad limit switches?
Sorry for not describing the problem in full the first time.


Thanks
Louie

[Robert]

Hi Louie,

About to leave due to severe weather. Yes, it is most likely a bad sequencer and yes, most likely bad limit switches as well.


The limits should have cut elements off when it got too hot.


If you call toll free to 1-877-263-7860 between 9 AM and 12 noon CST and from 1:30 PM to 4 PM CST you can order by Visa or Mastercard.


Mark, Lise or Carol can help you. Give them your furnace model number and they can give you price on the limits, replace them all, probably 1 or 2.


Then place order for the sequencer I quoted and the limit(s).


Just tell them I quoted sequencer, but then after more info, suggested the limit(s) as well.


Thanks for inquiring and doing businewss with us.



Take care and best wishes,
Robert

[Louie]

Robert,

I got the sequencer and limit switches like you suggested and it's doing the same thing.
As soon as i turn the power back on the elements start glowing and the fan will not run. When i turned the power back on the t-stat was set to off it was not on heat or cool.
What do i need to check next?


Louie

[Robert]

Remove blower housing to look down inside at elements and see if ANY are touching the frame, have fallen, etc... ?


They are eveidently getting energized through a short that has bypassed the sequencer, thus reason blower motor is not coming on.


It isn't all that common, but does happen.


Testing circuits with a meter would be only definative way to know for sure what it is.




Thanks,
Robert

[Louie]

Robert,

Just to give you an update,yes the element on the top string in the back was touching the frame. So i bent them back up plus a little extra.
All though I found it easier to remove the elements instead of the blower.
Are there any ceramic fittings that i can add to the frame to prevent this in the future?
Thanks for your help and everything seems to be fine for now.
One other question i have, i have a small pocket thermometer with a probe on it and i laid it over the vent in the floor to check the temperature of the air coming right out of the vent and got a max reading of 133 degrees F.
Is this good,bad,normal?


Thanks
Louie

[Robert]

Hi Louie,

Did it come loose from a insulator or is an insulator missing ?


Would have to check to see if any are readily available.



The blower motor just has to have a few screws removed, disconnect wiring and slide it out.


Temp is fine.


Thanks,
Robert