Five Tips for Increasing Pool Heater Efficiency

If you’ve never run a propane pool heater before, you may be in for a surprise the first time you use it – especially if you run it before outdoor temperatures start to really rise this summer.

Here’s why: the average propane pool heater burns about 1 gallon of propane per hour per 100,000 Btus. Since a propane pool heater for a standard-sized pool (~21,000 gallons) outputs 400,000 Btus, you will burn about four gallons of propane per hour.

So how many hours will the heater run for? That requires a little bit of math (bear with us).

• By definition, a Btu (or British thermal unit) is the measure of how much energy is needed to raise the temperature of one pound of water by one degree Fahrenheit.
• A typical pool is 21,000 gallons, and one gallon of water weighs 8.34 lbs. This means you will need about 175,100 Btus to raise the temperature of a standard-sized pool by one degree.
• Pool heaters can operate between 80-95 percent efficiency; if we conservatively estimate using 80 percent as an average, a 400,000 Btu heater will actually output only 320,000 BTU’s per hour. Translation: if you run a 400,000 BTU heater for one hour (using four gallons of propane) you will raise the temperature in a 21,000 gallon pool by about 1.82 degrees.
• Now: If your pool temperature is 60 degrees and you want to swim in 80 degree water, you will have to run pool heater for 10 to 12 hours; the current per gallon cost of propane in CT is approximately $3.00.

  So the bottom line in this scenario:

  10 hours X 4 gallons per hour X $3/gallon = $120 to heat your pool.

This is an extreme example, of course, since you probably won’t need to raise the temperature in your pool by 20 degrees any time but late in the spring or early in the fall. But it does point out the need to do what you can to make your pool heater more efficiently.

So how do you do that? Here are five suggestions:

1. Use a pool cover – Evaporation accounts for 70 percent of a pool’s heat loss, so put a lid on it when it’s not in use!
2. Retain a pool temperature of between 78-80 degrees. Every degree you raise the temperatures increases energy costs dramatically; keep water warm, but not spa-warm.
3. Lower the thermostat when the pool isn’t being used – If you don’t plan to use the pool for a few days, cover it and drop the thermostat to 70 degrees. For longer periods, shut the heater off.
4. Install a fence or hedge to protect your pool from wind and heat loss.
5. Have your pool heater serviced annually – Like any fuel-burning appliance, a pool heater needs to be maintained regularly to run at its best. In fact, an annual pool heater tune-up will usually pay for itself in efficiency improvements alone – not to mention the long-term benefit to your pool heater that routine maintenance will provide.

Enjoying your heated pool? Great! Just make sure you’re not paying more than you need to keep It up and running. Sign up today for a Hocon Pool Heat Inspection and Tune-up – one of the many high value Home Comfort Solutions we offer our loyal Connecticut customers – to keep your pool heater operating at peak efficiency.