Heat Pumps and Electric Heating - Rheem Electric Furnace wont shut off

This central unit is from around 1976. I have posted on my site some pictures, including schematics and such. I can hear the thermostat relay click when it tells the heater to turn off, but the heater keeps running like it is told to run.Regular cycle for this unit is after the thermostat tells it to turn off, it will turn off the heating elements and run the fan for a couple of minutes and blow out the remaining heat. I'm going to try pulling the thermostat off the wall when it is stuck on and see if it turns off. Any help would be appreciated.

Rick

Pictures (http://www.5hales.com/furnace.htm)

is both heat and fan keeps running, or just the fan itself?

To save the hassel, remove the t-stat wire off of G on the air handler to see if it stops.

If it stops, then it may be the stat. If it don't stop, then it's the fan relay in the air handler.

Everything is running, heat and fan. There is no Green wire used, just the red and white, simple basic heat only operation.

Everything is running, heat and fan. There is no Green wire used, just the red and white, simple basic heat only operation.

Ok, then see what happens when you remove the R wire.. I'd say you may have a stuck relay coil.

Right now the thing is working fine. Next time it gets stuck, Ill try that.

Also, if you look at the pictures, I have a couple of jumper wires that have burnt insulation, I want to replace those, but do not know where to get the premade or even the parts. They are right angle crimp-on connectors (dont know the name of them). I think they are like 12AWG, at least the RED wires are. I checked HomeDepot and all there crimp electrical connectors are straight and have insulation on them (it'll just melt).

I have a couple of jumper wires that have burnt insulation, I want to replace those, but do not know where to get the premade or even the parts.
Can be that the stab on's where not tight. That will like cook the wire that way sometimes

Hey Rick,

I found this site because I have the exact same problem. It sometimes just blows by the thermostat setting and you come home to 78 degrees. Mine is the 'Rheem Heating Center' model number AQP 14F 20 1

This one also has the burnt wires at the coil connections.... those coil sections broke and I guess the internal fuses didn't kick in and the wiring bought it.

Its done it off and on over the years and I'm on the third thermostat (now digital).

I'll shut off the breakers to get the furnace to stop and let the temp work its way down. NOT RECOMMENDING THIS -> while it was running on recently, walking by the unit hit it on the upper right corner of the box/frame (by door) with my fist in frustration...and it stopped. It went about running normally after it crossed the set temp. SO - from the vibration from the hit, I'm thinking that it could merely be a loose connection or a connection that has dust in the way. Once it stops - If it stops - this morning, I plan on turning off the breakers, look and tap connections and vacuum out the inside of this thing and see if it improves.

PS - I'm wanting to research for parts to get it back to 100% (fix coils,burnt wires, controller) but after the heating season. several years ago had tech service and they basically just restrung new coil through the heating blocks and hooked things back up. When the coils eventually break over time, short, burned wire-melted plastic. This unit had a humidifier addon so there's an openable panel in the duct over the coils and you can see which coils are orange or dark when running.

GoToe


those coil sections broke and I guess the internal fuses didn't kick in and the wiring bought it.

Sounds like you need more air from blower. Do you keep the filter clean???? AC coil clean ????

while it was running on recently, walking by the unit hit it on the upper right corner of the box/frame (by door) with my fist in frustration...and it stopped. It went about running normally after it crossed the set temp. SO - from the vibration from the hit, I'm thinking that it could merely be a loose connection or a connection that has dust in the way.
Works all the time . First thing we tell people to try when the blower stays on. You need a new relay there . the points have ark and burnt on it inside . So it can stick and not stick you never know. Also not turn the blower on . That will take out the elements for sure.
When the coils eventually break over time, short, burned wire-melted plastic. This unit had a humidifier addon so there's an openable panel in the duct over the coils and you can see which coils are orange or dark when running
With a meter Ohm out the elements to see if they are bad.

So, know one knows where to get the parts to make the female quick disconnect jumpers for the connections? I am having a hard time finding the non-insulated ones, I'm guessing they will melt. Should I just use regular stranded copper wire (10awg or 12awg) and your typical straight female insulated connectors and cut the insulation off? Picture link is down below on the original post.