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Michael Reush
Michael Reush, RV Technician
Category: RV
Satisfied Customers: 3249
Experience:  Serving the rv industry since 1977
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rv..coleman..few minutes..very loud humming noise and started slowly

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I am an RV tech with a Coleman basement heat pump issue. It's a model 6796A821 that would start up and run for a few minutes then the fan would stop. The fan made a very loud humming noise and started slowly. With a new cap it won't run at all. The unit is installed in a '92 Albion 5th wheel basement.

I cannot find any information on this unit other than the generic wiring diagram for the control board.

I suspect the thermostat as it hadn't been touched in a couple of years and the heat/off/cool switch doesn't feel right...soft "clicks" and mushy stops.

Any and all info or a link to a service manual would be great!

Ken's Camper & RV Service
Newport, NC

Hi There!!!


Thanks for Choosing Just Answer....


THIS should be the service manual for this series... I would look at the fan first since it started very slow and made a noise, the bearings may have seized up, I believe on these units there is a tiny spot you can put a few drops of oil in. Checking the selector switch is also a very good idea, the capacitor was replaced so probably not the fault... I hope that manual helps, if you have any other questions or concerns please feel free to contact me... I feel your pain on this one, I know some of these basements units are a royal pain to pull out..


Thank You!!! Please hit ACCEPT for my efforts, Positive feedback and BONUS welcomed!!!


Customer: replied 8 years ago.
this manual does not apply to the unit. It covers the 6799 roof top units but not the 6796 basement unit. I have this one and it's not really any help as the components and wiring are different.



NO Luck finding this particular model, I went through all the stuff I had laying around... So at this point I am going to Opt Out, this will allow other RV experts to respond, I want you to have the correct information, I understand it is crucial for troubleshooting this unit... I do not know when another RV expert will respond...


Thanks, Robert

Hi, this is Michael, I'm real familiar with this unit. First of all to see if the thermostat is sending a signal to the unit, when looking at the control board, you will see a green light towards the top, if it is receiving a signal it will be blinking......Now on the white plug with small multicolored wires towards the center, this is the thermostat wiring, ck the purple wire, and the black wire, the purple is for low fan, and the black wire is for high fan. I apoligize if I am telling you something you already know. Is the schematic missing from the back of the electrical cover plate? Ck the amperage draw when the fan does come on, this will tell us if its the motor..............Michael...........................I had a second thought: is it the interior or exterior fan that is the problem?
Michael Reush, RV Technician
Category: RV
Satisfied Customers: 3249
Experience: Serving the rv industry since 1977
Michael Reush and other RV Specialists are ready to help you
Customer: replied 8 years ago.
I found a broken neutral at the contactor. I repaired that and then discovered the fan motor is so rusty it seizes after about 10 minutes. It's old enough to have oil cups but it was too late. This is a single motor unit but if nothing else I can probably get it out of Grainger's catalogue.

Thank you for your time and efforts!

Great!!!!!!!!!!!!!!!!!!! Thanks for accepting, Michael