Cold Weather Heating Question

[Qwert66]

When boondocking we use heating blanket feed from PSW inverter and furnace to keep the wet bay from freezing. When shore power is available we use 2 cube heaters in the coach and 1 small one (200 watts) in the wet bay. We have the pillows in the 2 fantastic fan openings and nothing in the 2 layer shower skylight. We close all shades at night. We are very comfortable (and never worry about safety without pets) and can maintain basically whatever temp we need tested up to 80 degrees in outside windy 15 degree f in a 40' 1999 coach.

Granted when boondocking the LP wont last forever and in very cold weather it may take 2+ hrs for the cube heaters to raise the heat from 35 to 74 but we are always comfortable and feel safe.

We feel the 2 cube hearers are a better option than using our 2 heat pumps due specifically to the replacement cost and efficiency. Yes every season we test our cube heaters for safety including tip over, and overheat due to flow restrictions, and outlet wires heating up, and then may leave them unattended for 2+ weeks without worries. Using 2 provide a sort of backup to freeze concerns.

If we ever have to replace the Fantastic vent covers we will use the newer 2 layer insulated ones.

Just our mileage yours will vary.

[PyrateSilly]

We use an electric cube heater in the back that is temp controlled. Only comes on when below the temp we set it at. Right now the temps at night are only around 40 or so. Any colder and we then put on the electric mattress heating pad. For the front we put in an electric fireplace that gets turned on right now in the morning to take what chill there is off while getting ready for work.

If you are going to do a heated mattress pad or heated blanket I would do the mattress pad. It uses less electricity than a blanket.
8 Easy Projects for Instant Home Energy Savings - Renewable Energy - MOTHER EARTH NEWS
Unlike electric blankets, the power consumption for mattress pad heaters is very low (about 0.15 kWh per night).

[wyorancher]

Originally Posted by SuperGewl

On my unit the Rear AC only has Heat\AC the front unit has Heat\AC\Elec Heat. It is the one that controls the Heat pumps in both units. I place the bedroom on Heat and the Living 'room on Elec. Heat and they both with run the Heat Pumps, that is unless it's too cold then it will turn on the regular Heater.
Yes during Heat Pump operation the air comes out of the AC vents and yes its a tad bit cooler at first, but it does warm up.

I like to run my furnace to keep the wet bay from freezing although I do have heat pumps

[jerichorick]

I suggest reading the owners package for your system. We have 3 heat pumps on the roof. As previously stated, when the outside temps drop below 40 degs, depending on the heat pump configuration, it will just blow cool air. There is a differential factor of about 6 degrees built into the system. If the outside temp locks out the heat pump the inside set temperature will drop about 6 degs before the gas furnace starts. It will then take over and heat up to what the thermostat is calling for. The operators manual may explain this more clearly.

[georgetown350]

I run the furnace occasionally just to make sure it still works as we mostly use the heat pumps.

[wyorancher]

If I set temp on my heat pumps if they can't handle the heat required the furnace kicks in. The problem with heat pumps and portable electric heaters is they don't put heat into your wet bay. You may save a few $$$ on propane but have frozen lines in your wet bay.

[chboone]

Don't have heat pumps, have heat strips in both roof AC's, plus furnace. They work much better then heat pumps. Maybe your AC's can be retrofitted with heat strips.

Chuck

[HVAC Bill]

You can and should add heat strips to your heat pumps, they are designed to operate at low outdoor temps. but by design, they are pulling heat from outside and delivering it inside. The colder it is the less effective they feel. They also have to go thru defrost cycles and without heat strips they will basically blow a/c into your coach. There should be no reason you could no run both heating systems at the same time on cold nights. Bill

[jerichorick]

Originally Posted by HVAC Bill

You can and should add heat strips to your heat pumps, they are designed to operate at low outdoor temps. but by design, they are pulling heat from outside and delivering it inside. The colder it is the less effective they feel. They also have to go thru defrost cycles and without heat strips they will basically blow a/c into your coach. There should be no reason you could no run both heating systems at the same time on cold nights. Bill

Good idea, Bill, but the Coleman thermostat is not setup to run both systems simultaneously. As mention by some of the posts, running the gas furnaces in freezing weather is important so that freezing will not occur in the basement. Working to defeat this feature could be a major inconvenience and expense.

[JohnFreyja]

Can Heat Strips be added to existing Air Conditioners? Replacing good units doesn't seem practical.

[HVAC Bill]

In my coach the gas heat is wired thru the front thermostat only, but both are heat/cooling stats. You may need to replace the thermostat to allow for multiple heat functions, dont know what you have installed, there is no need to replace your current heatpump to add heat strips. Bill

[chboone]

Originally Posted by JohnFreyja

Can Heat Strips be added to existing Air Conditioners? Replacing good units doesn't seem practical.

You should be able to add the heat strips. You will need to check with the manufacturer of your units. I have Dometic AC's and their 5 button thermostat, it has two zones. The front zone 1 controls the AC, heat strip, and furnace. Zone 2 for the bathroom and bedroom controls the AC, and heat strip.

Chuck

[Cat]

We added heat strips to our 2 coleman 13500 heat pump-A/C. What happens as per airxcel (Coleman AC people). If you have selected electric heat your heat pump will turn on to maintain the temperature. If the heat pump will not keep up the inside temperature to what you set thermostat , once the temperature is 5 degrees below the thermostat it turns on the gas heater. Once the temperature is back up to the set point then the gas heater turns off. If you have heat strips in your heat pump AC . Once the outside temperature drops to low for the heat pump ( freezing) the controls will automatically shut the heat pump compressor off and turn on the heat strips, if the temperature inside the motorhome drops 5 degrees below the thermostat temperature it automatically turns the gas heater on until the temperature rises then it shuts the gas heater off. This is the operation of the Coleman AC - heat pumps with the Coleman wall thermostat in a 2007 MH. Not sure how it works on older or newer or for different manufactor.

[JohnFreyja]

Bill, Chuck & CAT,
Thanks, and I'll be looking into adding the heat strips.