Good morning folks! I have a 2013 Montana 3900FB with an air conditioner problem. The existing main unit is a Dometic 15,000btu unit. On a recent three-day trip we discovered it was running but not making cold air. I went top side, checked all connections, tested the capacitors, the high temp sensor on the compressor and all are working as designed. Turned the unit back on, fan started immediately and after the timeout on the thermostat cleared the compressor came on. Let it run for an hour an discharge temp was 64 degrees. Seems like I need a new unit. There in lies the problem. I contacted Dometic service trying to determine what unit would be the direct replacement. The tech told me the mfg# for me would be HT541816A711CO. (He was not very helpful). I searched the internet and have been unable to locate this model. The replacement unit I'm told is a heat pump style which is not what I have at present. This unit has a 1530btu reheat coil. Does anyone have any ideas as to what I should be looking for? Apparently the Blizzard units require additional wiring which looks to be a real problem getting run in the unit. It would seem to me this should be a relatively simple replacement but I'm not getting that feeling from what I've seen.
Good morning folks! I have a 2013 Montana 3900FB with an air conditioner problem. The existing main unit is a Dometic 15,000btu unit. On a recent three-day trip we discovered it was running but not making cold air. I went top side, checked all connections, tested the capacitors, the high temp sensor on the compressor and all are working as designed. Turned the unit back on, fan started immediately and after the timeout on the thermostat cleared the compressor came on. Let it run for an hour an discharge temp was 64 degrees. Seems like I need a new unit. There in lies the problem. I contacted Dometic service trying to determine what unit would be the direct replacement. The tech told me the mfg# for me would be HT541816A711CO. (He was not very helpful). I searched the internet and have been unable to locate this model. The replacement unit I'm told is a heat pump style which is not what I have at present. This unit has a 1530btu reheat coil. Does anyone have any ideas as to what I should be looking for? Apparently the Blizzard units require additional wiring which looks to be a real problem getting run in the unit. It would seem to me this should be a relatively simple replacement but I'm not getting that feeling from what I've seen.
Perhaps reach out to your favorite rv place and see what they would recommend as a replacement. One would assume that there would be a few different options available. Or maybe do some sleuthing and see if your model of rv had more than one ac option.
I just checked out the e-trailer website and it appears that Advent makes a direct replacement for my Dometic. Actually I'm on hold with them right now. I need to confirm that it will work with a two zone thermostat before I order it. I really like the Furrion unit but its not compatible with Dometic. Thanks!
Well, that did not work out at all. Etrailer told me that the 15,000 btu Advent air conditioner was a direct replacement. Well it isn't! When it arrived I checked it out compared with the existing Dometic unit and the wiring does not match up with the reported 6 prong quick connect in any way, shape, or form. Etrailer put me in contact with ASA electronics who informed me that the unit was not compatible as a replacement for the Dometic Duotherm unit. Not sure where this is going but I will contact Etrailer in the morning to find out what can be done. They have been up front about this the whole time but it seems nobody has an answer for this. If any of you campers have any ideas I'd certainly appreciate your input. Thanks.
Good morning folks! I have a 2013 Montana 3900FB with an air conditioner problem. The existing main unit is a Dometic 15,000btu unit. On a recent three-day trip we discovered it was running but not making cold air. I went top side, checked all connections, tested the capacitors, the high temp sensor on the compressor and all are working as designed. Turned the unit back on, fan started immediately and after the timeout on the thermostat cleared the compressor came on. Let it run for an hour an discharge temp was 64 degrees. Seems like I need a new unit. There in lies the problem. I contacted Dometic service trying to determine what unit would be the direct replacement. The tech told me the mfg# for me would be HT541816A711CO. (He was not very helpful). I searched the internet and have been unable to locate this model. The replacement unit I'm told is a heat pump style which is not what I have at present. This unit has a 1530btu reheat coil. Does anyone have any ideas as to what I should be looking for? Apparently the Blizzard units require additional wiring which looks to be a real problem getting run in the unit. It would seem to me this should be a relatively simple replacement but I'm not getting that feeling from what I've seen.
From your description I think you just froze up the evaporator coil. If you had 64 deg at the discharge it was probably like 85+ outside and the unit is working as expected. Nothing wrong with the A/C just high humidity.
Ram Montana High Country ... not all A/C's are compatible with the control and thermostat wiring in Montana's. It's next to impossible to adapt the Montana thermostat wiring to Advent A/C's. You also have to get a unit that is designed for ducted or non ducted RV's depending on what you have OEM.
If it were me I'd go with the heat pump unit and install the new thermostat for it. We have a heat pump and love it.
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Dick, Joyce, Diego, Picatso and Gustav
2017 3720 RL, and 2013 HC 343RL
Pullrite Hitch, IS, Disk Brakes, 3rd AC, Winegard Traveler, Bathroom door mod, Dometic 320, couch for desk swap, replaced chairs, sun screens, added awnings, etc.
Okay folks, let me answer some of the questions. When this all started I was able to check all of the system operation. No, it was not a frozen evap coil. I do have a background in AC so I know what to look for. The one thing I could not determine was if there was a leak in the 410 gas as I could not find any residue build up on the outside of the system. All the capacitors checked out the voltage and amp readings appeared correct. The unit started the fan and after the time out setting the compressor came on and kept running. After an hour of operation there was still no cool air from the unit. 80 degree ambient and discharge temp at 72. I will be tapping into the refrigerant system very soon but its a moot point at this time. It appears to me that all the supposed technical help I've been directed to knows less than I do about the operation of this unit. I sent photos of the existing control system to the techs from Advent and pretty much the techs had no answer other than it would not work with the Advent unit that Etrailer assured me would work. I don't know what Dometic system they were talking about (even though I give them MFG#, serial#, etc.) and they claimed it would be a simple plug in connection. The six prong connector is not compatible with the Dometic control board so at this point I'm sitting with a brand new unit that I can't use. I can not believe that replacing an AC unit on a 2013 Montana can be such a problem.
MONTANA brother, I have a 2008 38 foot RL rear living room w 4 slides.....LUV it...so does MAGGIE the dog. My 15000 BTU dometech kicks the breaker off at peak HOTT run times. (100' in Fla) I priced out new unit....I said to myself....this is gonna suck. Guess what I did, 8000 BTU GE unit at Walmart and threw it in a window.......BOOM !! Now I have 23,000 BTUS aghhhhhh we like it , feels like an IGLOO. The freakin' 8000 was 238 bucks.....260 OUT the Door ! Hooray for Walmart. I'm Marco and I drive race tracks (SEBRING, MIAMI homestd)
Cwesti, thanks for the info. Finally got the correct answer from Dometic and you nailed it down with the instruction manual. I still can't believe it was such a hassle to get this from them. I've ordered the correct unit and am waiting for delivery. I'll post again once I'm up and running. Thanks again!
I just replaced my 15000 dometic that never worked very well from new. Replaced with a Coleman model 48204c866 Mach 15 and added a model 47203B876 low profile Mach 8 plus Ac. Total job less than 4 hours labor.
I am well pleased units are very quiet and I can actually hear the TV on low sound setting. Also the camper has never been this cool. Like having central air at home. We are sitting in total sun at Raystown lake in PA.
HOPE THIS HELPS.
Cwesti, thanks for the info. Finally got the correct answer from Dometic and you nailed it down with the instruction manual. I still can't believe it was such a hassle to get this from them. I've ordered the correct unit and am waiting for delivery. I'll post again once I'm up and running. Thanks again!
Hi Nedbrod, I just came across your thread. I too have a 2013 Montana and the 541816-A711C0 unit that needs replacing. What unit did you end up purchasing, and how did the "direct replacement" work out? Do you have the Comfort Control Center 2 thermostat like I do?
Hi Nedbrod, I just came across your thread. I too have a 2013 Montana and the 541816-A711C0 unit that needs replacing. What unit did you end up purchasing, and how did the "direct replacement" work out? Do you have the Comfort Control Center 2 thermostat like I do?
Dometic sure does not make it easy for us.
Thanks in advance!
VagabondLove, Give me a couple of days to get back to you as I ended up getting a completely different unit that would match up with the Comfort control center. The Dometic unit they recommended did not work out correctly and had to be returned.
VagabondLove, Give me a couple of days to get back to you as I ended up getting a completely different unit that would match up with the Comfort control center. The Dometic unit they recommended did not work out correctly and had to be returned.
That is good to know...I would be very interested in what you ordered that did not work for you, especially given that this morning I spoke with Dometic technical sales line (800-544-4881) and they were actually helpful once I got through.
According to the specialist, Yes indeed the H541816Axx1C0 is the new model number for my old 541816A711C0. The "H" prefix stands for "High Performance" as a nod to the previous model name before it became a "Blizzard Nxt 15.0" Air Conditioner. The 1C0 is simply the color (white) of the shroud. 1J0 refers to a black shroud. So, it should be a direct replacement for my original unit, and nothing new should be required (except setting the dip switches correctly) since I am already using the CCC2 thermostat.
I expect the unit to be installed in October when I get my new FlexArmor roof, so I will post a followup update then, but I am definitely looking forward to hearing which model *did not* work for you and what you ended up with instead.
RAM 22' DRW 3500 Crew LB 40 gal reserve tank / RETRAX Bed Cover / 2020 373RD HC / IS / MOPEKA Tank Monitor / Furrion Side&Rear Cameras 
Linear Mode
