Need help with furnace and batteries

[Tdebard]

I bought my 2015 Flying Cloud last May. We used it several times through the summer and fall, and when we tried to go on a winter trip, I could not get the furnace to work. My thermostat has no “furnace” option, only heat pump, auto, cool, fan, and off. The prior owner told me to just set it to “heat pump” and that will use the furnace to maintain lower heat (I.e. set it to 50 and the furnace will keep it from getting colder than that). I’ve never been able to get the furnace to come on and even blow, not even cold air. I checked the fuse in the main box and it is fine

I made what I think is a big mistake…I used a space heater, and I left the airstream plugged into shore power for months while the batteries were not in “store” mode. When I unplugged over Christmas and checked, they were blow 10.

Question 1) are my batteries probably game over? I recharged them, put them on store, and now they’re reading upper 12’s, but I’m wondering if they will have a hard time maintaining.

Question 2) any advice on the furnace? After some initial research I think I need to check on my sail switch, but it seems that has more to do with igniting issues, not complete failure to blow.

[Tdebard]

I should add, I have also verified I have plenty of propane and that the line is open. Stove lights fine

[ROBERT CROSS]

You may get an abundance of varying advice...the only thing I will advise is...get new batteries charge them fully and re test the heating system.
Once corrected and it's time to store, charge them again and disconnect them completely until your ready to use again

Bob
🇺🇸

[s1000pre]

The furnace and heat pump are two different units, turning on the heat pump will “not” engage the furnace. If you have two zones, make sure you are on zone (1), this is the zone that will display your furnace settings. As long as you have good batteries, you don’t need to be plugged in to use your furnace. Be aware that running the furnace without being plugged in will deplete your batteries to 50% within 6-10 hours (with healthy batteries)

As Bob recommended, I would replace your batteries. Once they are drained that low, reliability becomes an issue.

[Tdebard]

One thing I didn’t think to mention, I replaced the AC unit myself the weekend after I bought it. There are two wires in the AC unit associated with the furnace, both the same color. I read in the somewhere that it did not matter how you wired in the two furnace wires (both blue), just hook them up to the two blue wires in the trailer. but am now wondering if that was not the case, and my wires are crossed

[Tdebard]

Ok, I figured it out. My Airstream only has one AC unit, therefore one zone. I doubt anyone will ever be in the same position as me, but thought I’d post the issue in case anyone ever runs into this.

There are dip switches on the Dometic Penguin II AC unit inside the unit. Everything comes in the “off position” with the exception of the heat pump on this unit. However, there is a dip switch for the furnace. I had not switched it to “on” when I installed it. If you ever swap out your AC unit yourself, make sure you do this. If you don’t, you won’t have a “furnace” setting on your thermostat. I also took lots of video during the process, so message me if anyone ever needs some video’s of how to replace it.

[s1000pre]

Originally Posted by Tdebard

Ok, I figured it out. My Airstream only has one AC unit, therefore one zone. I doubt anyone will ever be in the same position as me, but thought I’d post the issue in case anyone ever runs into this.

There are dip switches on the Dometic Penguin II AC unit inside the unit. Everything comes in the “off position” with the exception of the heat pump on this unit. However, there is a dip switch for the furnace. I had not switched it to “on” when I installed it. If you ever swap out your AC unit yourself, make sure you do this. If you don’t, you won’t have a “furnace” setting on your thermostat. I also took lots of video during the process, so message me if anyone ever needs some video’s of how to replace it.

Noted, good info. Glad you figured it out

[azflycaster]

The converter in a 2015 unit will most likely boil your batteries if left plugged in over a long period. I would suggest new batteries and a new converter. There are several ways you could go at this time depending on your needs and your budget.

[Tdebard]

Newbie question, what should I be concerned about with the converter? Currently everything is working normally. Batteries are staying in the 12.6 range. I can swing new batteries and a new converter, but don’t want to unnecessarily. I have a trip coming up where I will be hooked into shore power. What’s the risk if I want to see how my batteries and converter hold up on my trip?

[s1000pre]

Originally Posted by Tdebard

Newbie question, what should I be concerned about with the converter? Currently everything is working normally. Batteries are staying in the 12.6 range. I can swing new batteries and a new converter, but don’t want to unnecessarily. I have a trip coming up where I will be hooked into shore power. What’s the risk if I want to see how my batteries and converter hold up on my trip?

Very low risk, I went a couple years plugged in up to 30 days at a time and never boiled batteries. I eventually upgraded to lithium due to insufficient power from the stock 80’s.

[Mikebrady62]

Originally Posted by Tdebard

Newbie question, what should I be concerned about with the converter? Currently everything is working normally. Batteries are staying in the 12.6 range. I can swing new batteries and a new converter, but don’t want to unnecessarily. I have a trip coming up where I will be hooked into shore power. What’s the risk if I want to see how my batteries and converter hold up on my trip?

As s1000pre stated- very low risk. I leave my AS in the garage year round plugged into 110v ac whenever we are home. I have done this since it was new in 2019 and still have the same batteries from when I purchased it. They just lasted 2-1/2 days boondocking in November of 2022.
But as azflycaster noted, a 2015 might be a different story. Still very low risk if you are going to be plugged in anyway. Great time to test the batteries to find out how long they will last.

Happy Camping!

[azflycaster]

Airstream went to a multi stage converter in 2018.

[Life is a Highway]

So the quote on the day is “ Don’t be a DIPSWITCH “ LOL

Thanks for sharing this - Glad you figured it out heat pumps are not like a working gas furnace when it’s COLD


[QUOTE=Tdebard;2657168] Ok, I figured it out. My Airstream only has one AC unit, therefore one zone. There are dip switches on the Dometic Penguin II AC unit inside the unit. Everything comes in the “off position” with the exception of the heat pump on this unit. However, there is a dip switch for the furnace.