Community Forums

darjacob · 01-15-2022, 05:30 AM

I may be hypersensitive since I installed a new thermostat, but I noticed that when I select electric heat (heat strip) the heat exchanger fans come on as well. Has anyone else noticed that?

MRUSA14 · 01-15-2022, 07:41 AM

Quote:

Originally Posted by darjacob

I may be hypersensitive since I installed a new thermostat, but I noticed that when I select electric heat (heat strip) the heat exchanger fans come on as well. Has anyone else noticed that?

By heat strip I assume you are referring to the electric heat portion of the AquaHot (??) In that case it is a heating element which heats the Aquahot boiler fluid. That fluid does not heat the coach until it is circulated to the heat exchangers and the heat exchangers blow cold air past the exchangers and it gets into the coach as warm air. So yes, the heat exchanger fans have to come on to warm the interior of the coach, regardless whether the heat source is gas (diesel) or electric.

The only way to heat the coach without the heat exchangers cycling on and off would be to use the heat pump cycle on your air conditioners (which doesn't work below the low 40's ambient temperature), or the fireplace if you have one.

Aangulo1 · 01-15-2022, 07:48 AM

So my guess is that you changed your Tstat to the new micro air wifi one, correct? So are you saying that when you run the heat pumps the fans on the heat exchangers come on? Or what exactly are you referí g when you say heat strips?

bevandtomH · 01-15-2022, 08:24 AM

Jack, mine does the same and did so even with the old thermostat just as Marc says. My registers shut down after a minute or so. Consider it normal.

If any wants to upgrade, I highly recommend it.
Go to the Micro Air site and enter your coach info.
My particular model is the 354 but your coach may have a different model spec’d.

Marcosdad · 01-15-2022, 01:06 PM

Quote:

Originally Posted by MRUSA14

The only way to heat the coach without the heat exchangers cycling on and off would be to use the heat pump cycle on your air conditioners (which doesn't work below the low 40's ambient temperature), or the fireplace if you have one.

Well actually one can heat the coach by using the floor heat. The heat exchanger fans will not cycle in that mode.

darjacob · 01-15-2022, 02:16 PM

I guess I wasn't very clear with my question. I am talking about the heat strips in the A/C's. the fans in the heat exchangers come on with the A/C's heat strips. Anyway, it's OBE, bevandtomH answered the question for me. Thanks bevandtomH (aka Tom).

Gary.Jones · 01-15-2022, 02:50 PM

Let me get something straight....

There are no "electric heat strips" in the roof air conditioning units on our coaches like their might be at home. What there are are heat pumps, and heat pumps are just the AC units operating in reverse.... moving heat from outside to the inside in winter and from the inside to the outside in summer..... am I wrong on this?

Large Central Air Conditioning units like I have in my house in Louisiana have heat pumps and work as AC units in the summer and heaters down to about 40 degrees in heat pump mode (AC units in reverse). Then if the temp goes below ~ 40 degrees, I do have massive sets of electric heat strips located in the evaporator units up in the attic that kick in in phases to produce heat through the whole house system when the ambient temperature is in the 30s or below. If one bank of heat strips cant keep the house at the set temperature, then a second massive bank of electric heat strips kick in and is able to keep the house warm down to way below zero. However, those heat strip banks consume massive amounts of electricity.

It is my understanding that our roof AC units on our coaches are effective down to about 40 degrees and then have nothing else to kick in or "give". My understanding is that roof AC units on our coaches have NO electric heat strips.

Correct me if I am wrong.

Gary

deckape · 01-15-2022, 03:05 PM

No heat strips in a RV heat pump a/c.

darjacob · 01-15-2022, 03:50 PM

Got it, no heat strips in A/C's. But there are heat elements - right?

MRUSA14 · 01-15-2022, 04:44 PM

Quote:

Originally Posted by darjacob

Got it, no heat strips in A/C's. But there are heat elements - right?

No heat elements either. The only thing that provides heat from your roof units is air conditioner working in reverse. And as mentioned above, it won't work below 40 degrees. Actually you can feel it fading below 45 degrees.

And yes Stew, you are correct. I forgot about the floor heat as a heat source.

Gary.Jones · 01-15-2022, 05:15 PM

No, there is no ability for the AC units to do anything other than work like an AC unit in reverse..... it is a heat pump, and there is no electric element in the unit that can provide heat. There is only the heat outside in temps higher than about 40 degrees that the heat pump can pump into your coach in winter..

After you get down to 40 degrees, then the only sources of heat available in our coach are the AquaHot or the fireplace.... that is it. So, when I know the ambient temperature is going to fall below 40 degrees approximately, then I turn the heat pumps off and turn on the AquaHot on heat mode. No sense in having the AC/Heat Pumps turned on at all in temps of ~ 39 something degrees.

Now, the Aquahot has an electric element in it just like an electric hot water heater in a house in addition to the diesel burner (or on Insignias, the propane burner), but in my experience the electric heating element of the AquaHot is not sufficient to heat the coach in cold temps.... It is capable of heating 4 or 5 gallons of water sufficient to run the dishwasher or wash you hands in hot water, but it is not sufficient to heat your coach.

Gary

jmorse1 · 01-15-2022, 05:25 PM

Think of it like your window air conditioner....you stick it in a window and it blows cold air into your room and hot air outside. If you remove it from the window and spin it around it will blow cold outside your house and hot inside your room. That works well but it gets really old to have to spin that thing around every time you need cooling or heating. So it's accomplished mechanically through your thermostat.

Hope this helps!

John 2015 44b

BEACH · 01-15-2022, 05:32 PM

We used to have a 1988 Xplorer 36’ DP. The ceiling A/C units did have electric heat strips. They were excellent on chilly fall/spring mornings to take the chill out of the coach.

96 Wideglide · 01-15-2022, 05:40 PM

Quote:

Originally Posted by BEACH

We used to have a 1988 Xplorer 36’ DP. The ceiling A/C units did have electric heat strips. They were excellent on chilly fall/spring mornings to take the chill out of the coach.

I've been waiting for someone to mention those old things!

Your not going to find them in any mid to high tier RV.