Heat pump vs electric heater

[rthomaslyons]

As a retired Power Engineer I could likely compute the efficiencies and heat calculations and figure this out myself but I also know that we operate our toys under less than scientific conditions.

So here is the question: Is the RV AC/Heat pump more efficient than an electric heater which is for the most part 100% efficient? And under what conditions does it work best because it does use electricity as well.

[5picker]

Short answer... no.

The heat pump uses as much or more electricity to produce less heat.
You are running a compressor and a fan to produce that heat which is then affected by efficiency/inefficiency of ambient outside temps on the system.

[SlowrideHD]

The advantage is that the heat pump circulates the air better, in my case anyway.

[TitanMike]

Originally Posted by 5picker

Short answer... no.

The heat pump uses as much or more electricity to produce less heat.
You are running a compressor and a fan to produce that heat which is then affected by efficiency/inefficiency of ambient outside temps on the system.

Actually, a heat pump (without electric heat strip) does not "produce" heat, it merely moves it from outside air to inside. An AC unit in reverse.

If one is using a heat pump in ambient temps above 40 degrees they are pretty efficient as it takes less electricity to move the neat (energy) than it does to produce it with resistance heat units.

That's where the efficiency falls like a rock. Once there isn't enough heat present in the outside air then the heat pump needs a separate heat source to make the interior spaces warm enough. Most common is a heat strip installed in the unit although larger ones use gas/propane.

Only real advantage to a Heat Pump is that it's also an A/C unit and there they are pretty efficient.

If someone is more of a "Resort Camper" and has plenty of power available a heat pump might be the way to go, especially with a larger RV.

Remember, it's all about "Energy". Heat pumps move it from outside to inside when heating. If there's not enough "energy' outside (usually below about 40 degrees) to move, then it has to be created and it's back to an electric heater or furnace.

FWIW, Heat Pumps rock when Geo-Thermal heat is available. Rather than blowing air through collection coils, pipes are inserted in the earth where they absorb heat from the hot (or very warm) ground water.. No make-up heat units required and tons of money is saved by not having to "create" heat.

[rthomaslyons]

Originally Posted by rthomaslyons

As a retired Power Engineer I could likely compute the efficiencies and heat calculations and figure this out myself but I also know that we operate our toys under less than scientific conditions.

So here is the question: Is the RV AC/Heat pump more efficient than an electric heater which is for the most part 100% efficient? And under what conditions does it work best because it does use electricity as well.

Good answers guys, that would be my thinking on this as well, on my unit it looks like if the outside temperature is too low the thermostat calls on the propane furnace in the HEAT MODE even if the furnace is not selected.

[Kenpet50]

I agree with previous replies, but, if electric is free, and only need to warmup coach in early morning, if would use a small ceramic heater, less wear and tear on the heat pump.

[TitanMike]

Originally Posted by Kenpet50

I agree with previous replies, but, if electric is free, and only need to warmup coach in early morning, if would use a small ceramic heater, less wear and tear on the heat pump.

Nothing's free. You paid for the electricity when you paid your site fee. Some even have meters and if you use more than the "allowance" you get charged about 4 times what the power company charged to deliver it to the campground

One place I stayed had an "allowance" of $30/month for electricity. That worked out to about 240 kwh or about 5 hours per day of run time for a 1500w electric heater. Easy to go over your allowance if you add to all the other power uses while hooked up like Water Heater, Converter, Microwave, TV, Entertainment System, Phone Charging, etc.

I use a couple of small ceramic type heaters set on low output and their thermostat set just high enough to keep the furnace from running at night when camping in cold weather in a full hookup site. Saves propane.

[transmission_doctor]

A couple of basic points, most RV's are not wired to power space heaters. A typical space heater is 1200 to 1500 watts, that will likely pop breakers in most RV's which have 15 amp circuits.

The next major point is that heat pumps are WAY more efficient than space heaters. Typically a heat pump will produce 4 or more BTU's for EACH BTU of electricity consumed. Modern mini split heat pumps WILL continue to function well, down to below zero Fahrenheit.

[TitanMike]

Originally Posted by transmission_doctor

A couple of basic points, most RV's are not wired to power space heaters. A typical space heater is 1200 to 1500 watts, that will likely pop breakers in most RV's which have 15 amp circuits.

That's why I set mine to the 750 watt setting and make sure that each heater is on a separate circuit. One in bathroom and one in kitchen area. Max current draw for both combined is 12.5 amp.

[Joe_GA]

Originally Posted by transmission_doctor

The next major point is that heat pumps are WAY more efficient than space heaters. Typically a heat pump will produce 4 or more BTU's for EACH BTU of electricity consumed. Modern mini split heat pumps WILL continue to function well, down to below zero Fahrenheit.

Exactly right. Heat pumps are more efficient than resistance heating. When my AC units need replacement, I'll go with heat pumps as long as there are enough control wires run to my units. And, I'd much rather not have clunky heater boxes and power cords getting in the way.

[tomkatb]

Comparing heat pumps to resistance is fairly easy.

Under good circumstances they use roughly 50% the electricity as resistance heat. It does not heat. It moves heat from the outside into the rv.

Their disadvantage is cost to install. Also they are not much below 40 degrees so you need a back up anyway.

The air circulated by a heat pump is likely below 95 degrees. Colder than the human body. The DW will likely not like the cold breeze on her.

Only guessing the cost of the heat pump is likely similar to the rv gas furnace minus the hassle of frequently filling the tank.

We have had one since 1992 in our house. Natural gas is not available here. In addition we get a special rate from the electric company in the winter.

In out fiver we use the fireplace and a small $20 electric heater with the lp for back up. Only used lp once last year.

I sort of wish I had paid for it in our new rv. Not very expensive.

[Hoglou]

We heat pump in mild weather, but we break out this puppy when chilly goes to down right cold.

[NorSnrub]

My Coleman a.c. has a heat strip but no heat pump. It works at below 40 and all temps. I use it to supplement, the gas.