Thermostat

[sdhabberstad]

My furnace option does not show up on the thermostat to even turn on the furnace, any idea why or how to fix it?

[BayouBiker]

this comes up a lot unfortunately and there are many causes. Describe your setup and components or year and style of trailer. One or Two A/C? Dometic CCC2 thermostatic controller?

Here are some common causes: furnace has no 12V power, furnace controller faulted or failed, bad wiring to furnace, AC controller bad.

[sdhabberstad]

Originally Posted by BayouBiker

this comes up a lot unfortunately and there are many causes. Describe your setup and components or year and style of trailer. One or Two A/C? Dometic CCC2 thermostatic controller?

Here are some common causes: furnace has no 12V power, furnace controller faulted or failed, bad wiring to furnace, AC controller bad.

I have a 2006 28’ International. The thermostat is a Duo-Therm comfort control. I find it odd the furnace option would just disappear. The converter was recently changed also.
Thanks for your response.

[BayouBiker]

the CCC2 automatically senses what to control and what to disable. There are dip switches on the Dometic AC/Heat Pump, whatever you happen to have that determines what the CCC2 controls. It also senses a semi-isolated low voltage signal from the Furnace via a two wire connection.

Performing a system reset will cause the CCC2 to read the dip switch settings again and it may then detect the presence of the furnace. Do a reset by setting the ccc2 to off and then press and hold zone and mode at the same time. When it says init release and then press the on/off button. See if it now sees the furnace. If not remove 120 V and 12V power (use/store switch) then reconnect power and try again. Removing power resets the AC unit controller firmware.

Let me know if this works (it does sometimes).

Edit: yours may be the older CCC not the comfort Control 2, in that case after pressing and holding the zone and mode simultaneously switch the unit to ON, it should show FF in the display until you release the two buttons.

[pmclemore]

My furnace setting was set to read "Aqua" for some reason. That works just fine - but you can reset the word to "Furnace" if you want. I don't remember exactly how, but if this is your issue, someone here will remember.

Pat

[BayouBiker]

Good catch Pat, the dipswitch is for an external furnace or aqua heating system, the controller can't know the difference so you have to tell it. On the CCC2 you press and hold the up and down arrows to toggle the display from one to the other.

[pmclemore]

Thanks, Brian. I was too lazy to go out to the trailer to check the manual.

On reflection, maybe she needs for me to go out there and see her. I've been neglectful for too long. Sob.

Pat

[Halford1]

is it possible for me to replace Dometic thermostat with Nest?

[sdhabberstad]

[QUOTE=BayouBiker;2359091]this comes up a lot unfortunately and there are many causes. Describe your setup and components or year and style of trailer. One or Two A/C? Dometic CCC2 thermostatic controller?

Here are some common causes: furnace has no 12V power, furnace controller faulted or failed, bad wiring to furnace, AC controller bad.[/QUO

Reset thermostat. Nothing. Been reading about dip switches. Wouldn’t know where to find them. Frustrating

[BayouBiker]

The dip switches are in the electrical box on the roof unit, outside. You access the box by first removing the fiberglass shroud. I'm going to assume it used to work fine, and so suspect the controller up top is the issue. did you cycle all the power off as well? If so, you can access the dip switches and flip it a couple times. Perhaps the connections corroded a bit. The control box is on the curb side. Inside is an electrical board with dip switches on it. the CCC model has a row of 8 switches and 5 is the furnace switch CCC2 has 10 and 8 is the furnace.

[sdhabberstad]

I did a full shutdown and nothing. Currently traveling cross country so I will climb up to the AC when I get home. The heat pump is handling the cool evenings for now. Ill keep you up to date when I get this resolved next week . Thanks so much for you help.

[BayouBiker]

Here's hopping you resolve this. So we're on the same page, you have just one AC unit and the ccc is only showing one zone, right? As you flip through the options, which ones display currently?

[sdhabberstad]

Finally arrived home. Climed on the roof removed the air conditioner cover to reveal the dip switches. I’ll now reference them as dip sh—s. There were 8 and all labeled about the 4th one that said furnace was up and the remaining down. Pushed it down nothing. Pushed it up as it must of settled somewhat in the middle and it worked. Now I have a fully functioning board. Thanks so much for you help. You saved me hundreds of dollars I’m sure.
This is my fourth Airstream and I’m really beginning to wonder but now that I’m a master airstream mechanic I best stick with them. Ufdah!!! Thanks again.

[BayouBiker]

Glad to hear it worked out!