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mooseye
Oct 4, 2009, 03:21 PM
I have the above electric furnace and I need some help troubleshooting it.
I was able to make the unit work by jumpering a couple of the wires. I know this is not safe but so was freezing and I didn't leave it unattended. I have a meter and I have 240 volts to and out of breakers and to most of the wires on most of the components in the control panel. I need to know how and in what order to check the individual parts such as limits and sequencers.

hvac1000
Oct 4, 2009, 03:56 PM
First establish that it didn't blow out the transformer. Make sure you have 24VAC low voltage coming from LOAD/SECONDARY side of transformer.

Also check for any blown fuses in circuit. Then jumper one limit switch at a time to see if any of those are open.

That is a very old unit and I do not have a wiring diagram for it so you will just have to test the components as you choose.

Need parts or other info go here and post your request under Nordyne since Intertherm is nor nordyne. These folks are pro's on mobile home units

Index page (http://www.mobilehomerepair.com/phpbb/)

mooseye
Oct 4, 2009, 04:44 PM
Thank you for your reply.
I have signed up on the board you linked to but hae not yet received the activation email.
I just checked every terminal on every componet and had either 121v or 30v.
If I jump the connections on what I think are the sequencers, the element will heat up.

hvac1000
Oct 5, 2009, 01:33 AM
If you are jumping out the sequencers to get the heat on (elements on) then either the low 24 volt control voltage is missing that activates the sequencers or the 24 volt activation circuit in the sequencers themselves are defective. Remember the sequencers low voltage circuit also act as a simple time delay device to prevent initial high voltage circuit over draw and instant high voltage demand which will cause light bulb dimming and other such things. Also different sequencers will have different timing delay times so replacements should be of the same design and timing.

mooseye
Oct 11, 2009, 12:19 PM
If you are jumping out the sequencers to get the heat on (elements on) then either the low 24 volt control voltage is missing that activates the sequencers or the 24 volt activation circuit in the sequencers themselves are defective. Remember the sequencers low voltage circuit also act as a simple time delay device to prevent initial high voltage circuit over draw and instant high voltage demand which will cause light bulb dimming and other such things. Also different sequencers will have different timing delay times so replacements should be of the same design and timing.

I have discovered that the control heater seems not to be working. The stage switches (sequencers) and a what I think is a limit switch are mounted on a metal plate assembly with the control heater inside. I assume that if the control heater is not working that the stage switches will not engage. Is this correct and can it be bypassed or will I need to replace the entire stage switch assembly?

hvac1000
Oct 11, 2009, 07:01 PM
You cannot safetly bypass the controls.