Forest River 3171DS AC Not Working

dburlison · 07-26-2015, 08:11 PM

I have a 2014 Forest River 3171DS that has less than 7,500 and the roof mounted AC is not turning on. The RV has been in storage for at least a month without being used/started. I started it today, turned on the generator and turned on the battery bypass (so the generator could charge up the batteries). I let the generator run for 5 minutes, and then I turned the AC thermostat to cool. Nothing happened. I cycled through the settings and nothing. I tried just the fan and still nothing. I checked the circuit breaker to make sure it wasn't tripped. I checked the roof to make sure it wasn't damaged or vandilized, but it appeared ok. I turned everything off, and let it sit for 5 minutes and tried again. I'm new to RVing and I've only owned the unit for a year... So, I'm hoping the unit isn't broken, but that I'm missing something. Any ideas?

bruceatlam · 07-26-2015, 10:03 PM

Can you plug in to power rather than run your generator?? Have you checked your batteries --- how do they check?? What's the volt reading??? If they're low, charge them up first.

VinceU · 07-26-2015, 10:13 PM

Quote:

Originally Posted by dburlison

I have a 2014 Forest River 3171DS that has less than 7,500 and the roof mounted AC is not turning on. The RV has been in storage for at least a month without being used/started. I started it today, turned on the generator and turned on the battery bypass (so the generator could charge up the batteries). I let the generator run for 5 minutes, and then I turned the AC thermostat to cool. Nothing happened. I cycled through the settings and nothing. I tried just the fan and still nothing. I checked the circuit breaker to make sure it wasn't tripped. I checked the roof to make sure it wasn't damaged or vandilized, but it appeared ok. I turned everything off, and let it sit for 5 minutes and tried again. I'm new to RVing and I've only owned the unit for a year... So, I'm hoping the unit isn't broken, but that I'm missing something. Any ideas?

Is it Dometic? They seem to be having problems recently. My neighbor just had his exchanged, 3 months old. Have seen numerous on here (forum) also.

dburlison · 07-26-2015, 11:46 PM

Hi VinceU, yes it's a Dometic thermostat. Are these thermostats going bad?

dburlison · 07-26-2015, 11:48 PM

I don't have access to plug it in to power. The batteries are at about 1/3 charge. But I thought the AC would turn on when the generator was running - even with low batteries. Do the batteries need to be at full capacity?

VinceU · 07-27-2015, 08:12 AM

Quote:

Originally Posted by dburlison

I don't have access to plug it in to power. The batteries are at about 1/3 charge. But I thought the AC would turn on when the generator was running - even with low batteries. Do the batteries need to be at full capacity?

Yes they must be close to 12 for thermo to work. With Gen. on they should over 12 volts with charging current are breakers closed on gen control panel. Anything else like microwave work with gen on? A few other appliances need 12 VDC to work with AC power.

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Myrle · 07-27-2015, 12:44 PM

Alot of them the freon wasn't up to specs. I have a 2014 FR Sunseeker. It worked a little first year then went south on. They have a two year warranty.

Myrle · 07-27-2015, 12:47 PM

Easy to check termostat does the furnace come on?

nikita · 07-27-2015, 02:46 PM

We have a 2015 Sabre, bought in December. Ran the living room AC for 3 months in Florida. Everything fine. Camped a weekend in June and its running luke warm, second campout, luke warm. The compressor was shot. Under warranty, replaced with a brand new AC!! Works fine, end of story (I hope!).

TonyH · 07-27-2015, 03:22 PM

You might check the compressor fan on the unit. In humid conditions, rust can form on the shaft causing it to bind up. Mine has done that a couple of times. WD 40 and spinning it by hand frees it up nicely.
When it is stuck, the a.c. will hum but will not move air.

Cornelius · 07-28-2015, 02:04 AM

The Dometic roof air conditioners require 12 volts to power a relay circuit board. If your 12 volts was low, the automotive style fuse on the circuit board may have blown due to too much current being drawn. The circuit board is located in a metal box that is visible when you have the air filter removed. Be sure to disconnect 120 volt power before opening the box to check the fuse, as the high voltage is also in an adjacent section of the box.

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