2005 Minnie Winnie AC now not as cold

[Matthew]

I was at the RV over the weekend and noticed it took hours to cool the coach down. Normally, even in the hot Florida sun within an hour it is cooled down.


I was there working on a (non RV) water heater issue on the property so I did not have time to do an inspection on the AC. I did pull out the filter and clean it. The coils were not frozen which is what I was expecting.



The AC will eventually cool down the RV but it is certainly not as cold was when we bought it less than a year ago.


Looking at the paperwork I got with the RV it looks like the AC is from RV Products and I am guessing that would mean it is a Coleman. It is duct-ed and maybe 13,000BTU.



Next time out I plan on taking off the hood and cleaning the coils and inspecting for a freon leak. I understand that if it is low on freon then you just throw it away.


If I need to replace it, 20 years later I hope things have improved and maybe we have some inverter technology in AC units now for RVs?


Any suggestions?


TIA
Matthew

[bigb]

Originally Posted by Matthew

I was at the RV over the weekend and noticed it took hours to cool the coach down. Normally, even in the hot Florida sun within an hour it is cooled down.


I was there working on a (non RV) water heater issue on the property so I did not have time to do an inspection on the AC. I did pull out the filter and clean it. The coils were not frozen which is what I was expecting.



The AC will eventually cool down the RV but it is certainly not as cold was when we bought it less than a year ago.


Looking at the paperwork I got with the RV it looks like the AC is from RV Products and I am guessing that would mean it is a Coleman. It is duct-ed and maybe 13,000BTU.



Next time out I plan on taking off the hood and cleaning the coils and inspecting for a freon leak. I understand that if it is low on freon then you just throw it away.


If I need to replace it, 20 years later I hope things have improved and maybe we have some inverter technology in AC units now for RVs?


Any suggestions?


TIA
Matthew

First of all you should measure supply and return air temps to see if you really have a problem. You should see approximately a 20F degree delta between the two. It can vary depending on the condenser temperature and the humidity so I wouldn't condemn it right away if your delta is a few degrees lower. Be sure to measure your temps as close to the plenum as possible.

Definitely remove the shroud and clean the condenser, a dirty condenser makes for high head pressure, more current draw and poor cooling. Be careful as the fins are very fragile so don't go shooting high pressure thru them or you could bend them. Clean the indoor evaporator as well. I use a coil cleaning product in a can from Home Depot for both coils and the lid doubles as a fin straightener/scrubber. It's usually easier to access the evaporator from the top by removing a sheet metal cover, then cover the floor inside in case of drippage. It's also a good time to clean out the evaporator drain and trough and check condensate pump operation if equipped.

If the evaporator is really dirty brush it down first dry with a soft brush, I use one of those long thin brushes made for cleaning refrigerator coils.

If the coils have not been cleaned in 20 years they could be pretty dirty.

edited to add more info

[Matthew]

Ok sounds good. I will also check the air temp just to be sure very humid Fl air is not messing with me...

[bigb]

Originally Posted by Matthew

Ok sounds good. I will also check the air temp just to be sure very humid Fl air is not messing with me...

I edited my original post to add more info, and here is the product I used on mine last month: https://www.homedepot.com/p/AC-Safe-...-921/206740351

PS you don't necessarily need to rinse the indoor coil especially in high humidity as the condensate will rinse it, but the outdoor coil is dry. I rinsed my indoor one with a spray bottle and distilled water and the outside one with the garden hose sprayer turned to a low pressure.

[Matthew]

Yep that is what I use and I like the cap to help straighten the fins

[creativepart]

We have a 50-amp coach with two rooftop A/Cs and in 93+ temps outside and very high 80's inside it takes far more than an hour to cool down the coach. More like 5+ hours. And our A/Cs are both putting out chilled, dry air in the ~25 degrees colder than outside temps, indicating they are working fine.

I think you'd find that it sounds like your system is running fairly normally.

These RVs have lots of windows and much too little insulation to both fight the heat outside and cool down with a lone A/C unit pumping out as much cold air as it can.

This is why we run with our generator running non-stop on travel days working to keep what little cool we have left over from overnight inside as we're driving through the heat and humidity.

[Matthew]

Could very well be as we have never used it during the hot humid summer. I think it was 91 degrees in Arcadia Fl on Saturday with probably that much in humidity.


It seemed like an hour to cool down (I am sure it was much more than that), we would open up the RV and go out to dinner and come back and it was freezing inside.

[Morich]

I would suggest check the temps and then also look for things that might block any air. Both in the vent system inside but also for things like birds or rodents building a nest of junk in the rong place up top.

I know it is often just throw away to the repair folks but if the freon is gone, one of the things they balk at is adding a tap to the freon lines to replace the freon!
It takes finding the guy with the right attitude that wants to do good work and save you a bunch of time and money but putting a tap on a freon line is very much the same when on top of an RV as when stanidning out back of your house!

Rv folks are often not treated as if they have much sense!

[Matthew]

I agree.. just put a charging tap on there, put your gauges on it and fill it up!


I have already thought of an AC guy that is of the same mindset as me... if man made it man can fix it!

[Morich]

the obvious downside is that there may be some reason freon is leaking and that can get too much but for me, the first step is to find if the freon is the problem and look for leaks. That part is pretty much like we have on the automotive AC and it rarely requires a full AC changeout.
The big difference that I think of is the auto air has more places and longer lines to let things leak! On a rooftop unit, the leak can't be much more than 4-5 feet away and you don't have to get the radiator out of the way to look!

[Ray,IN]

RVP typically was the distribution branch of ColemanMach for their basement heat pumps/air conditioners. Do you have a basement unit or rooftop unit?

[Matthew]

I have a rooftop and it is a heatpump.