Heat Pump and Propane Heater


New member
May 19, 2007
I live in Maryland and have a heat pump that has worked fairly well. I have been able to swim into October (I also have a cover). Now that the temperatures, particularly at night, are dropping the heat pump is having trouble. I want to keep swimming. I was wondering about the possibility of having both a heat pump and a propane heater. I would use the heat pump most of the time, but when it starts to get too cold for the heat pump, I would use the propane heater to give the heat pump a boost. Does anyone have experience doing something like that and does that work? Thanks.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
Yes, that works. Keep in mind that in Maryland, with fairly reasonable electric rates, the propane heater is going to be signficantly more expensive to operate then the heat pump. With the total amount of heat required increasing as it gets colder, the total cost to heat the pool will go up significantly. You can keep running the heat pump during the day for a while yet, but this time of year in Maryland they get fairly inefficient at night.

You might want to think about solar heating. It won't be as reliable as the other two, since it depends on the weather, but it will be significantly less expensive. Combined with a heat pump, solar could get you several more weeks at either end of the season and cut your heating costs significantly.


Well-known member
Apr 30, 2007
If you are going to stay in your home for a number of years you might want to investigate a ground based heatpump rather than your air heatpump. It extracts heat from the ground and will work well in the colder weather as well - but you would be trading lower operating costs for higher capital costs.

You could always just buy a wetsuit :)


TFP Expert
Apr 15, 2007
Ft Lauderdale, Florida

Some heat pumps will not operate when the ambient air temps fall below 50 - 55 degrees because it starts to freeze up. Colder climate (and very warm climate) regions can opt for the Heat N Cool feature that will allow the system to run at even lower temps, but, the trade off is much reduced BTU output.
Gas is really the only way to ensure that you can heat the water, when it gets too cold out for the efficiency of the Heat Pump, or desire to increase the temps quickly.
To answer your question, the idea of using the gas to help/suppliment the heat pump is done all the time. However, as Jason said, your operating cost will increase due to the gas heater.
I cannot emphasize enough, how important the use of a solar cover is in retaining the heat you've put in. Without a blanket, you're losing 50% or more of the heat overnight, that you've put in during the day. A blanket retains an additional 30%, so you lose approximately 20% of the heat.

Geothermal heat pumps is another option, but it looks like you already have a heat pump on your system. If you've got an additional $10K to part with, I'm sure I can get one of my local dealers to install one for you. :wink:


New member
May 19, 2007
Thanks for the feedback. I do have an automatic cover on my pool. Without that and the heat pump I would not have been able to swim as long as I have which is to late October. I guess I was enjoying it so much that I wanted to keep swimming. I am not looking to make a major capital investment, I was just hoping to swim maybe another few weeks to what has already been a relatively long season and maybe start a little earlier, say early to mid-April instead of May. The gas option doesn't sound bad from a start up cost perspective, about $2000. The operating costs (using the propane) I understand will be much higher than using the heat pump. I was hoping that if I just used the gas in small amounts to raise the temperature early in the morning that the heat pump could help keep the water warm during the rest of the day without having to use too much gas. Does that make sense?