Coleman A/C icing up

[Jeff&Angie]

I have a 2022. GD 337RLS. My rear air conditioner is a Coleman 15k that came ith a RV Airflow device from the factory. After running 30-60 minutes in 85 degrees or higher outside temp, it ices up. I have checked the install of the airflow and sealed all cracks with foil tape. I will notice the air not coming out of the vent much and i can hear a difference in the sound of the fan. I then switch it to hi/fan only for 15-30 minutes. The fan sounds change and the vent starts blowing. I then know its time to switch back to cool/hi/auto. When cleaning my roof i noticed a brownish, sticky streak running from the a/c to the left rear drip point on the side of the roof. Don't know if this is related or not. What else can i do for the icing? We full time so i really cant take it to the shop for weeks. I'm thinking maybe a mobile tech. Ideas on what could be causing this??

[howson]

I have a 2022. GD 337RLS. My rear air conditioner is a Coleman 15k that came ith a RV Airflow device from the factory. After running 30-60 minutes in 85 degrees or higher outside temp, it ices up. I have checked the install of the airflow and sealed all cracks with foil tape. I will notice the air not coming out of the vent much and i can hear a difference in the sound of the fan. I then switch it to hi/fan only for 15-30 minutes. The fan sounds change and the vent starts blowing. I then know its time to switch back to cool/hi/auto. When cleaning my roof i noticed a brownish, sticky streak running from the a/c to the left rear drip point on the side of the roof. Don't know if this is related or not. What else can i do for the icing? We full time so i really cant take it to the shop for weeks. I'm thinking maybe a mobile tech. Ideas on what could be causing this??

Welcome to the forum. Since that was your first post, please check out the Welcome Letter to New Members here: https://gdrvowners.com/forum/main-fo...to-new-members

An easy(!) fix is if the freeze sensor dislodged from the evaporator. Check out https://gdrvowners.com/forum/operati...ir-conditioner

Your problem, unfortunately, could be because the air conditioner has lost refrigerant. I've attached an old Dometic bulletin that speaks to the issue (all these rooftop units have a similar working process). Assuming the installation of your Airxcel Coleman is OK (which it reads like you've already checked) the conditions spelled out on page 6 may apply. If that's the case the only recourse is to replace the top unit. They cannot be serviced.

Dometic Air Conditioner Frost B - Dometic.pdf

I've also attached a Coleman-specific manual for your reference.

Airxcel Evaluating Air Conditio - Airxcel.pdf

Please report back with what fixes the issue. The power of this forum is owners helping other owners. You can help by documenting what resolves the problem.

Howard

[Country Campers]

I would think that the brown sticky stuff may not be good.

I have found that in high heat and or humidity to run the ac on low fan all of the time. This slows the air movement and almost completely stops icing up. We have done this since talking with a Dometic Tech in 2018 at a Rally when ours froze up and quit running, it was in the high 80's and very humid. After switching to low fan we have not had any issues. If it is to cool down over night we will switch to auto mode so it will shut off at sometime then back to low fan for the day time.

Brian

[Jlawles2]

Check that the temperature ice probe in the evaporator has not become dislodged or mis placed preventing the unit from self protecting from icing. Our front AC had the probe come out and I noticed it while cleaning the filters.

The gooey discharge could be any number of things. I would suspect some type of sealer that was used. You may need to pull the cover on the unit and see if there are any signs of something that has started to deteriorate.

[Jkwilson]

Run the fan on high all of the time. Lack of air flow and low refrigerant are the primary causes of icing. IMO, there should be no low fan speed option for this reason

[Jeff&Angie]

The ice sensor did not seem to be pushed into the fins very well. I moved it close to the side of and it fully inserted it. Testing now

[SolitudeAtLast]

We have thru this twice with the front (bedroom) Coleman a/c. If its freezing up, it will freeze the core down to the sensor described above, and then shut off the compressor for awhile. Coleman does recommend running on Hi fan in humid conditions. Anyway, at first it just doesn’t cool as well, and steadily get worse. If you call a mobile tech, have it running on Cool HI Fan for when they take their measurements. Loss of freon causes the evap core temp to be lower, resulting in freezing, esp as Lo fan speed. Our bedroom a/c has been replaced twice within the 2yr Coleman warranty. If there is a next one, guess it will be on us. Be sure you have checked the condenser core etc on top to be sure it isn’t plugged with leaves etc. I agree you should remove the top cover anyway to try to find what the streak of brown, sticky streak is (we didn’t have that). Also, if you are the original owner, you will need to have the Sale or Delivery date from your paperwork from the selling dealer. Colemans 2yr warranty starts on that date. So far, no problem with the rear Coleman in the living room. Also, it was our understanding from the mobile tech that the warranty replacements from Coleman are refurbished units. Good luck!

[SolitudeAtLast]

I forgot to mention that Coleman warranty does NOT cover the travel charges for the Mobile tech. Coleman covered their diagnostic time to troubleshoot it, and confirm that it needed to be replaced, and Coleman sent them the replacement a/c unit and covers installation labor. We had to pay for the techs “service call” travel time to come out. We used RV Doctors in Ft Myers, and they were used to working with Coleman warranty. Two Service calls each time; one to come troubleshoot it, and then another to replace it when new unit arrived cost about $125, so was not too bad.

[Jeff&Angie]

Still seems to be icing up but if i leave it run, it starts dripping water from the main vent and puddles on the floor. Maybe taking longer to ice than before

[howson]

Still seems to be icing up but if i leave it run, it starts dripping water from the main vent and puddles on the floor. Maybe taking longer to ice than before

Unfortunately that probably means low refrigerant. Nothing other than a replacement will fix that. :(

[Jeff&Angie]

It was replaced by a remote tech under warranty. I paid for the service call.

[deanot26508]

I once covered the vent in the bathroom of my old camper, and without thinking about it, I too froze my evaporator. There are other things that can cause a frozen evaporator, low refrigerant, restrictions in air flow and or metering device.