New basement a/c problem

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The run caps for the indoor & outdoor blower motors are mounted inside near the motors.  I'm looking at the RVP 6535 Service Manual sketches and schematics.  It appears that the two blower motors don't have start caps.  Only the two compressor motors haves both start & run caps which are behind the metal access panel.     

I've been using the 50A Hughes Autoformer for the past 14 yrs on this coach and never had a capacitor failure in my basement unit and that's with 7 yrs fulltiming and a lot of a/c time.  Low voltage is a real killer on the start circuits and induction motors.  I don't have any first hand experience with cap problems. 

Your problem John, could be the outdoor blower motor bearings are so worn that the rotor is dragging against the stator.  That is a typical wear problem with my VW engine starter motor in my dune buggy.  I would open the access panel first to see if you can find a visual problem there.  Most likely you'll have to drop the unit to replace the run cap and pillow bearings and/or outdoor motor.

 
Ah-so, thanks for the explanation Bll (aka Mr. RVP  :D ) . The weather is really lousy (cold and windy) but when we have a nice day, I'll open the access panel and have a look-see.
 
John, while you are replacing the caps, you might want to consider moving them to a more accessible location.  I extended the wires and fastened them to the side of the cabinet and labeled them so I could tell them apart. All it took was a couple of holes, grommets and wires with ends. It has already paid off during my last episode.  There were some pictures taken but now I cant seem to find them.
 
 
I found the pictures, they aren't pretty but it works well. You may have more room inside the electrical compartment than I have since I got rid of the circuit board controller and replaced with components. This still leaves enough room for my slide in toolbox.

I guess this is an example of thinking "outside of the box" something that many engineers won't do or not allowed to do.
 

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John Canfield said:
Good job, I like your grommets made from hose - I've done the same thing.

Thanks John, This time I ran the hose thru the cabinet to the motor and used it like a conduit. Just too many things inside to rub against and besides I had the hose already.
 
I pulled my basement air a couple of months ago because the evap fan wouldn't run (bad run capacitor.) While I had the unit out I moved the condenser fan motor run capacitor to the circuit board area.

Reinstalling the unit was a complete PITA due to the engine muffler heat shield blocking a straight vertical lift. Finally after hours and hours of frustration I discovered that the trick was to lift it up several inches and then push in towards the engine and then lift more. I did buy a lift table which I consider a necessity for my model of HVAC (the blower outlet is horizontal and not vertical like some models.)

By the way, I bought the new plastic version of the squirrel cage blower but didn't need it - my unit already had the updated version. I also have two new pillow block bearings for the condenser fan I don't need - my fan bearings were fine, I just gave them a few drops of 30W oil.If anybody needs these parts, send me a PM. The parts are spoken for (3-30-2019)
 
Duner said:
I've been using the 50A Hughes Autoformer for the past 14 yrs on this coach and never had a capacitor failure in my basement unit and that's with 7 yrs fulltiming and a lot of a/c time.  Low voltage is a real killer on the start circuits and induction motors.  I don't have any first hand experience with cap problems. 
A very compelling argument. Started doing some research on my iPhone. While playing a game of Word With Friends, after playing a word, an ad from Hughes Autoformer show up offering a 10% discount and free shipping using the code FACEBOOK10 so I bought one. Man that's scary how your phone rats you out to businesses.
 
Thought I'd reply to this old thread, as I didn't see a how-to explanation for removing, servicing,and replacing a basement unit. Here is an excellent how-to pdf written by Bill Elsenpeter:  https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxiaWxsbWFyaWUyMDA4fGd4OjRmOGYwYzBiZTYxYzU5ZWQ
 
Thanks for putting up Bill's document, we have it somewhere else but this is a good thread for another reference. Bill is a retired engineer so that's reflected in his technical writing.
 
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