Addning heat strips to heat pump AC units

[mchero]

I have two ac/heat pumps, both same models on my 07 Discovery. The units are running w/o issue BUT I'd like to save my propane & install some heat strips.

Has anybody done this before? I have located heat stips for Coleman AC units but I need to check & see of the controller had the plug (2 pin) for the heat strips.

Roof units are model 8534C8797. Both function 100% but when the temps are down below 40 the heat pums don't function well.

I found this Heat strip;
http://www.adventurerv.net/coleman-camper-roof-air-conditioner-heat-strip-add-p-708.html?gclid=CjwKE...

[pianotuna]

Hi,

Nothing cheap about the cheap heat system. I heat 100% electrically. Low last night was 10 F (-12 C)

[Pirate1]

Have you looked at cheap heat, heating element installed in the gas furnace?

[dougrainer]

EACH Heat Strip (5600btu/hi fan) pulls a TOTAL of 13.5 to 15.5 amps depending on which model RVP AC or HP you install it on. you will drop 1 amp for med or lo fan speed. So, it does NOT matter what shore power you are on, the Heat Strips are as much of a Amp hog as the HP mode. Doug

[mchero]

Yes, TWO heat pumps.

Thansk

[Pirate1]

dougrainer wrote:

mchero wrote:
I'm not planning to use heat stips all winter long. I do relize that it will NOT keep the rig warm below freezing. It's just late fall when I'll be using it.

Spent some time last night reading & found that the AC units I have DO have the option available for heat strips. I found two at $40/strip.

My older 93 Pace Arrow Diesel has two older rooftop units with heat strips as well.

Thanks for all the information.

This we understand. But, WHY, Install the Heat Strips when you have the Heat Pump to do the warming when above freezing??????? Doug

x2. Didn't op say he had two heat pumps? I have one in my 37' motorhome and it kept it nice and warm down in to the high 30's.

[mchero]

Heat strip will supplement the Heat pump between 30 - 40 deg F. Anything below that & it will have to be Gas furnace or, in my case a small ceramic heater in the coach set at 40 deg and a 60W bulb in the heated basement. When I'm done for the winter (in about two weeks) I'll remove the perishables & winterize.
Deb & I are trying some winter camping this year.

Last weekend we stayed in an RV campground with just 30amp service. Woke up to about 35 degree temps & the heat pumps where not putting out much, if any heat.

The heat strips are about 40/pop & takes about 10 minutes to install. I'm not expecting to heat the coach with just the heat strips.


Thanks

[dougrainer]

mchero wrote:
I'm not planning to use heat stips all winter long. I do relize that it will NOT keep the rig warm below freezing. It's just late fall when I'll be using it.

Spent some time last night reading & found that the AC units I have DO have the option available for heat strips. I found two at $40/strip.

My older 93 Pace Arrow Diesel has two older rooftop units with heat strips as well.

Thanks for all the information.

This we understand. But, WHY, Install the Heat Strips when you have the Heat Pump to do the warming when above freezing??????? Doug

[Golden_HVAC]

It is much better to use a couple of portable electric heaters. Find them at Wal Mart for $15 - $25. Don't get the heavy oil filled ones, they are - well large, heavy and have to heat up to work, then cool off before storing them to move the RV.

I like a fan type, test the fan at the store (they have plenty of places to plug in cleaning equipment in the store) to see if the fan is quiet. They are the most compact, and blow out heat in the safe 90 - 110F range.

The large cone "Infra-red" heaters can warm clothing to the point it can ignite (saw a demonstration as a kid, never forgot about it) and are 'large'. The tiny ceramic heaters that I have seen put out heat well above 120F and do not move a lot of air, so they are out as well.

I will run one 1,500 watt heater on high and the other on low heat output, so the first is about 12.5 amps, while the second is 7 amps, to keep the total well below my 30 amp rating.

Have fun camping!

Fred.

[mchero]

I'm not planning to use heat stips all winter long. I do relize that it will NOT keep the rig warm below freezing. It's just late fall when I'll be using it.

Spent some time last night reading & found that the AC units I have DO have the option available for heat strips. I found two at $40/strip.

My older 93 Pace Arrow Diesel has two older rooftop units with heat strips as well.

Thanks for all the information.

[Wayne_Dohnal]

Everything I write here assumes your RVP/Coleman heat pump is the same as my 15 kbtu RVP/Coleman heat pump. Mine came from the factory with the aux heat strip installed. If the creators had executed the controls differently it would be a good option. As they did it, it's IMO not worth dealing with.

The aux heat strip provides 5,600 btuh, equivalent of a 1,640 watt heater. By comparison, the specs say the heat pump produces 12,700 btuh in standard test conditions with the outside temp 47 degrees.

The control of the aux heat strip is done completely in the roof unit. The thermostat doesn't know it exists. The roof unit has an outside temp sensor that cuts the heat pump off at about 40 degrees. If the heat strip is installed, the power that is cut off from the compressor is routed to the heat strip. With that background, here are the unintended consequences:

1) The roof unit forces the fan to run on high whenever heat is selected. High fan is IMO unnecessarily fast for use with the heat strip and they should be running it on low so the outlet air feels warmer and the noise level is lower.

2) Since there's no way to force the heat strip on, you can't "de-stink" it at the beginning of the season or before a trip. The result is that when you finally hit a cold day and the strip activates, it stinks like heck from not getting used for a long time, and you want to open the windows to get the smell out. Catch-22!

Having too much time on my hands I modified my upper unit, adding a switch to force the heat strip on (for pre-season de-stinking), and at the same time force the fan to low speed. Without this change, I'd never want to use the darn thing.

[pianotuna]

Hi,

If he has two that would produce 10,000 BTU's. I don't call that "a little heat". That said, last winter during the deep cold I was using about 19,000 btu's of electric heat.

DownTheAvenue wrote:
The heat strips in the A/C unit actually produce very little heat. You would be much better off just buying the little ceramic heater cubes for about $20.

[DownTheAvenue]

The heat strips in the A/C unit actually produce very little heat. You would be much better off just buying the little ceramic heater cubes for about $20.

[dougrainer]

Heat Strips only have 5600 btu's of heat EACH. You HP's have the full 13.5 or 15k rating. BUT in sub 35 degree temp, the Heat Strips will not do anything to heat the RV. Heat Strips were never designed to HEAT the RV. They were designed to take the chill off the morning or evening air. Doug

[mchero]

When it's cold out & we are connected to 30 apms or more it would be nice to save the propane! It's been working all summer till the temops start dropping!

Sunday morning it was about 35 deg. and the heat pums where not putting out any heat.

I'll report back on my findings. "IF" I find the proper plug.

Hmmmm at the bottom of the link...
This will NOT work with MACH 8 Air compressors or MACH8 Heat Pumps. Use Coleman 47233-4551. Don't think my units are reffed to as MACH 8..

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