A/C compressor cycling.

[Rick and Mindy]

When I started using my forward A/C unit this year ( the one with thermostat in bedroom), I noticed the compressor would run for a few minutes then shut off for awhile then kick back on and repeat this while I have it on. I think I have narrowed the problem down to the run capacitor going bad. Anyone else experience these symptoms and if so how did you resolve? Not calling an rv tech to have him tell me I need to replace unit. I'm getting cold air from vents when compressor is on.

[mstan]

How long does it take for it to cycle back on?
It is possible that the compressor is kicking out from a high prssure switch.

If you really feel it is the run capacitor then simply change it out. They are not expensive and is is a simple job. Just make sure you cut the power to the unit. And do not touch the terminals so as to discharge it with your fingers.

[Rick and Mindy]

I have ordered the run capacitor since it was not that expensive and I could always use a spare if that doesn't fix the problem. Just thought maybe someone had the same problem and diagnosed something different. Thanks

[mhs4771]

You don't have one of the Bedroom ceiling vents pointed at the T-stat by chance?? Would tend to shut the AC off before actually reaching the set temp. Just thinking of easy things.

[Rick and Mindy]

No I don't. The fan keeps blowing but I can here the compressor cycle. I've got a run capacitor on its way. It's an exact replacement. Hopefully that will solve the problem. We are in Louisiana under a pole barn and temps are getting unbearable so I'm not getting on roof until new capacitor arrives.

[XCMARK]

you may want to clean the coil outside , high head pressure from a poorly cooling outside coil can give you the same problems.

[mstan]

Originally Posted by Rick and Mindy

No I don't. The fan keeps blowing but I can here the compressor cycle. I've got a run capacitor on its way. It's an exact replacement. Hopefully that will solve the problem. We are in Louisiana under a pole barn and temps are getting unbearable so I'm not getting on the roof until new capacitor arrives.

I have mine in a pole barn also in Louisiana. I bet if you place a fan up there to circulate air across that condenser coil it will run. I have the same problem with my rear air. There is a safety switch that shuts the compressor down when the head pressure reaches a certain point. Cleaning your coils will help some. I hope the run capacitor fixes it. My bet is on high head pressure.

[Rick and Mindy]

Thanks. It could be a dirty condenser but I only want to go up there once if I have to so will look closer once the capacitor arrives. I figure I can always use a spare capacitor if that doesn't resolve the issue. I have been living in my 31sl for the last 2 years under the pole barn and didn't have this problem until this year. Luckily the rear heat pump is keeping our rig bearable (77-80 degrees) but runs steady all afternoon.

[Rick and Mindy]

So if I get up there and find a very dirty condenser what is the best way to clean it? Any suggestions. If I was in my house I would just take a water hose to the outsioutside unit. Never cleaned an rv condenser before.

[XCMARK]

pull off the top half of the plastic cover , make sure the unit is off first. let it cool off for 10-15 mins so the cleaners doesn't dry quickly. spray your condenser cleaner directly on the fins on both sides of the coil. then rinse it with a steady stream of water at 90* to the coil so you see the water come all the way through to the other side. Make sure your water isn't doing damage to the coil fins. I have used Zep purple power cleaner , simple green pro and commercial grade coil cleaners to clean out the condenser.

https://www.amazon.com/s?k=condensor...nb_sb_ss_i_3_9

[Rick and Mindy]

I will try to update on what I found. Decided to try and clean condenses first while waiting on my replacement capacitor. Noticed when I removed the shroud that the unit looked a little worn and the metal cover to the capacitors was bent but just figured maybe it happened during initial installation. Cleaned condenser and coil on my troubled unit and decided to clean the condenser on heat pump as well. Neither unit was very dirty but glad it got done. Test ran the troubled unit but still not operating as should. A couple of days later took my new capacitor up to replace it and wanted to check old capacitor first to see if it was ok. Guess what! Capacitor in the unit was rated at 60mfd instead of the called for 40. I check the model number and now I find out that the model is different than the model listed on my door inside but my heat pump is correct. Don't know if my listing of all my models was provided by factory or Exploreusa where I purchased the fifth wheel new in 2013. Now I suspect that for whatever reason, Exploreusa may have swapped the new original unit with one they were having problems with to satisfy another customer before I actually purchased it off the lot. After looking up the specs and finding out it was supposed to have the 40mfd capacitor I switched them out but it is still cycling on and of and when it does kick on it draws the power in the rig down for second or so. Needless to say I think for whatever reason the higher capacitor was put in there, that may have ruined the compressor. I have a hvac guy that can tap the line but wondering if replacing compressor would be feasible? Suggestions are welcome.

[mstan]

Rick, your AC guy will be able to check the compressor and how many amps it is drawing. Sounds to me that it is drawing to many amps and thus the overload switch is kicking it out. If it were me, I would take this opportunity to upgrade your unit. Do not try and change the compressor. This will only lead to more frustration. In my humble opinion. They don't cost that much and you can upgrade your unit to a more efficient one that will cool better. Easy job with a little help.

Mark

[XCMARK]

these units have a sealed refrigerant system , I would suggest you consider replacing the entire roof unit before you pay money for a service call.

[Rick and Mindy]

Originally Posted by XCMARK

these units have a sealed refrigerant system , I would suggest you consider replacing the entire roof unit before you pay money for a service call.

I am thinking along those lines.

[Pockets52]

I hope you got it fixed, I was having similar issues with my heat pump cycling. , mine was a 2016 model, ended up being the thermostat, replaced this past Saturday and works perfect.

[Rick and Mindy]

Originally Posted by Pockets52

I hope you got it fixed, I was having similar issues with my heat pump cycling. , mine was a 2016 model, ended up being the thermostat, replaced this past Saturday and works perfect.

Haven't got it resolved yet. I have been considering replacing the thermostat. How did you figure out that's what the problem was? Just by replacing it?

[XCMARK]

Originally Posted by Rick and Mindy

Haven't got it resolved yet. I have been considering replacing the thermostat. How did you figure out that's what the problem was? Just by replacing it?

Some of those RV thermostats are $180~200.00 , I did have a problem with mine 2 years ago. The heat pump would not turn on the and the Heat would not turn on. It ended up the slide contact was dirty and sliding it back and forth and spraying it with a little WD -40 was enough to get it working. Be careful if you try this not to let the oil get on the wood it could stain it. You could also get a wiring diagram for your current thermostat and jump the wires togeather but MAKE sure you take a picture of the colored wires on what terminals. The RV industry isn't known for following industry standards..... R isn't always Red wire . If you do replace it make sure you get the exact same model as what you have , this will help make it fool proof wit zero head scratching later. best of luck!

[Rick and Mindy]

I have unscrewed existing thermostat from wall to check wire connections. Lots of wires and connected with wirenuts. Not much extra wire to play with so hard to check connections. Considering removing full length mirror next to thermostat and cutting hole in wall behind it to get to all connections.