As the message indicates, I am having trouble with the HVAC system in my 2000 Lance 1030. The Atwood heater blows hot and won't stop, cannot be controlled by the thermostat, and the AC will not turn on period. I don't know if it is the thermostat, or what could be happening. I have to take the fuse out to get the heater to turn off. It was 100 degrees yesterday, and the heater wanted to just keep blowing hot. I have an Atwood furnace, and a Dometic Duo Therm Penguin AC unit, both controlled by a Duo Therm thermostat. HELP!!! :)

Thermostat would be my first thought and cheap to replace.Good luck

USAFBILL wrote:Thermostat would be my first thought and cheap to replace.Good luckDitto.

There is the possibility of this happening to all RV types, not just TCs. I think you will get more responses in the Tech Forum. I am moving the thread.WayneModerator

Thank you. I am just getting to know this site. I will be frequenting the 5th wheel section more, but I need to get my truck camper AC working! I guess I can start with a new thermostat. I am 'tarded when it comes to electrical. I could rebuild a whole camper, but tell me to troubleshoot electrical and I will weep like a small child!

Take the thermostat off the wall, make a drawing of where each wire is on the thermostat, then remove them. Now did the heat stop, if yes get a new thermostat, if no then a new one will not fix it. It could be a short it the thermostat wire or a problem in the HVAC unit.Dusty

HELP!! No AC, heat stuck on full- 2000 Lance 1030

restlessways
Explorer III
Jun 12, 2013
Thank you for the link. That board says for use with AC unit with heat pump. Does that matter? Nevermind, I notice they list different options.
restlessways
Explorer III
Jun 12, 2013
So, you think I should just replace the board? Also, I don't care what Dometic says as long as it works.

Here are some pics of my unit. There is a top view. A side view of the small board at the passenger side, and an interior pic looking up of an unknown electrical panel looking thing:
Flattop
Explorer
Jun 12, 2013
It could be the drive-shaft modual. That is what me and my brother always tell our wives when we need to get out of the house and drink a few. It buys us a couple hours anyway.
Chris_Bryant
Explorer II
Jun 12, 2013
That board is it. The only other relay is one in the furnace, but it can only make the blower run, cannot make the burner fire, and cannot affect the air conditioner.
Worse comes to worst, you can install the electronics and thermostat from the new versions of that model for under $100. Dometic might or might not approve of that, but....

Here you go- DuoTherm control kits.
restlessways
Explorer III
Jun 12, 2013
Is there only one board? I found a small one under the side sheet metal cover on the roof at the unit. I have no idea where this Atwood heater relay goes which the previous owner gave me. It is not on the board on the roof, or at the furnace.
restlessways
Explorer III
Jun 12, 2013
Gosh, this is not looking good. It sounds like I may have to replace the whole unit? I think they are over $1k.
Chris_Bryant
Explorer II
Jun 12, 2013
Well, I've had the Dometic AC Service manual online for years at http://bryantrv.com/docs2/docs/acservice.pdf- it's about #4 when you google duotherm air conditioner service manual. You could also Google Duo Therm customer support and come up with http://www.dometic.com/enus/Americas/USA/Customer-Support/.
restlessways
Explorer III
Jun 12, 2013
Is Dometic available to talk to? I cannot believe how hard they make it to find information about this unit. I cannot find anything. How can I be sure it needs a new board?
Chris_Bryant
Explorer II
Jun 12, 2013
Good news bad news- the board is located in the roof unit, so you do have to get up there to access it. The circuit board is no longer available, so you have to install a new thermostat/control kit- around $100 (or individual parts for around $70). I'm not sure if Dometic approves using one of those kits in this model.
restlessways
Explorer III
Jun 11, 2013
I have Dometic Duo Therm Penguin model # 620415.321, product # 991721731.