Roof Air Conditioner

The AC unit on the roof appears to be the original Penguin model. It cools well but doesn’t seem to be dehumidifying the air. I can’t see any condensate dripping off the roof outside either. Any ideas on what I should check for would be greatly appreciated. Thanks.

If it's cooling. its working.

Agree with @keelhauler.  De-humidification is a function of the air being cooled, not something separate.  So if it is cooling, then de-humidification is also occurring. 

Where are you at and what is the humidity level there?  If ambient air is at a relatively low humidity level you won't really see any condensate.  If you have access to a humidistat check the outdoor humidity and then the indoor humidity and compare the difference if any.

Another possibility is that the fan is set on high.  Seems odd but the A/C can cool too fast, bringing things down to temperature and then shutting off before it can pull much humidity out of the air.  Try the fan on auto or low.

The AC unit on the roof appears to be the original Penguin model. It cools well but doesn’t seem to be dehumidifying the air. I can’t see any condensate dripping off the roof outside either. Any ideas on what I should check for would be greatly appreciated. Thanks.

You are correct in being concerned!  If it is cooling, its working.  If you are in Tennessee right now, there is enough humidity that it should be draining condensate. If you are somewhere else, and unsure of humidity, are there other RV's running AC? See if they are draining condensate.

Did you remove and clean the inside filter? On ours, that was a problem. I had NO idea how dirty it was until I finally pulled it out. Made it humid inside, and caused the condensate to drip inside after a while. Easy fix, however. 

I would take off the top cover of the AC and investigate.  After removing the top cover, there is another cover inside that gives access to the evap coil and allows inspection of the inside. Make sure the evap coil fins are clean. There can be enough crud on them that it cools, but the crud acts like a sponge and keeps the moisture in. This allows it to cool, but not dehumidify.

With the cover off you should be able to see the path the condensate takes to drain, and see if the path is clear. A glass or two of water dumped into the evap coil area should readily flow out and show the path. If not....well thats why you are in there.   

Good Luck!

I’m in new Orleans and it’s like a river coming off the roof.

Aside from that

To be honest, if I can’t find a better option regarding the ac noise I’m going to have to get rid of this unit for one with a basement ac or ducted or quit the rv travel all together. How a person can sleep with these noisy rattle trap ac units us beyond me. I really want to hear one of the advanced rv units before pulling the trigger but I’ve had my fill of the noise.  Well That and the ac should be a bigger unit in the 2552.

Hi, thought this might be a bit of helpful info !    https://www.thefitrv.com/rv-tips/the-pursuit-of-quiet-replacing-our-rvs-air-conditioner-again/

To be honest, if I can’t find a better option regarding the ac noise I’m going to have to get rid of this unit for one with a basement ac or ducted or quit the rv travel all together. How a person can sleep with these noisy rattle trap ac units us beyond me. I really want to hear one of the advanced rv units before pulling the trigger but I’ve had my fill of the noise.

One mans trash...

At the last festival we were parked with the 'younger family' aka 'party all night' crowd. We were so happy to have the white noise generator on (that loud AC  ) to allow us to sleep in all the din.

Volkman.... yes, but is that every night for months on the road. It’s been a month so far and another 6 to 9 weeks to go.

pappy... Thank you, I’ll research that one as well. The advanced rv ac unit is claimed to be the quietest but I really  hope to experience the diff brands before pulling the trigger on replacing or some other alternative.

Volkman.... yes, but is that every night for months on the road. It’s been a month so far and another 6 to 9 weeks to go.

You are talking to someone who used to barrack next to the runway at Pease AFB as flightline security... KC135 's and FB111's will rock you to sleep there*, at uneven intervals. ...   The drone of my AC hardly is a bother.     I do understand that once it does get 'under your skin' it can be unbearable. Good Luck! 


Wonder if TNcanuk got inside his AC yet to ensure condensate is draining. Be quite the eye opener if it was disappearing into the coach...








*OK, was refreshing my memory of 'zactly what flew out of there back in '87, and found it was closed and turned into Air NAt'l Guard a couple years after I left.     Dont know what they fly out of there now.

Volkemon, thanks for the tips. I will check on the things you suggested. The inside filters are ok. Not perfect but ok!  I wondered if I just need to give it a thorough cleaning, so that’s what I will do first. When I posted this I was on my way from Tennessee to Canada but where we stopped was real humid. The camper trailer in the site behind us had condensate dripping continuously and we had none. Humidity level inside our rig was 74%. We are now in Canada on the shore of Lake Erie and the weather has been very cool and windy so there’s been no need for AC. I need to get working on it so we are ready when we need it.

My next problem is the water heater. It works perfectly on electric but not on gas. Lots of spark from the igniter but it won’t light. Probably also needs cleaning. Any troubleshooting ideas are most appreciated.

Volk.  even if I could go to sleep over the tin can full of ball bearings running if my better half is miserable as well, it’s a rough journey.

Volk.  even if I could go to sleep over the tin can full of ball bearings running if my better half is miserable as well, it’s a rough journey.

Sir, there you have it. Happy spouse happy house.  Were it not for the ladies that put up with us we would still be in caves. 

@TNcanuk -  I have yet to have to work on my water heater....so no guidance there. 

TN.... Did you find where the condensate was /is running?

TN.... Did you find where the condensate was /is running?

I removed the cover from the AC unit. The coils on the backside were filthy but the coils at the front where the condenser is was clean. I cleaned everything up and made sure the condensate drain was clear. That drain is on the driver side of the unit so now I at least know where to look when it’s running. However right now we are in Port Dover, Ontario with nice breezes blowing off Lake Erie. Highs in the upper 70s and lows in the low 60s with no humidity!  Wonderful weather, so I haven’t had the need to run the AC so far.