A pool heat pump is the best choice for economical, on demand pool heating. Sure, gas heats faster – but even at today’s lower prices, a gas pool heater can burn through thousands of dollars in natural or propane gas – every year.
Pool heat pumps use small amounts of electricity to compress a refrigerant and rotate a fan. The heat created is essentially free – absorbed from the outside air, and transferred into your pool water.
Depending on outside air temperature, your cost per kilowatt-hour, and whether or not a pool cover is used – heat pumps can keep a pool in the mid-80’s for $50-$150 per month.
The 4-P’s of Heat Pump Installation
Here’s an example of a heat pump project progression. The 4-P’s are phases of a swimming pool heat pump installation, and they are: Purchase, Placement, Plumbing and Power.
Buying a heat pump is not overly complicated, but you do want to size your heat pump correctly. If you are looking for a 20 degree temperature rise, go with the largest models, for an average size pool. Smaller models may only give you a 10-15 degree rise during cooler weather.
Decide if you want any of the high end features, such as the Chill feature, which removes excess heat from the water, or want extra low temp operation.
Heat Pump Delivery: Heat pumps are delivered by a long haul delivery company, and you must be present to inspect and sign for receipt. Inspect the unit by looking for any damage to the fins or cabinet, or any oily stains on the box that may indicate leaking refrigerant.
Be prepared for how heavy these are. Large pool heat pumps can weigh 350 pounds and are best moved by palette jack. Two strong people can carry it with 2-2×4’s inserted through the palette, and another person to help steady it while moving. Heat pumps need to be kept upright at all times, and could be damaged if dropped.
To prepare a location for placing the heat pump, consider this:
- Give air clearance of 18″ on sides and back, and 36″ in front.
- Give vertical clearance of at least 60″ to prevent recycling air.
- Level an outdoor A/C pad, or a concrete pad of 3-5 ft. in size.
- Place the unit and rotate for easy plumbing and control access.
By easy plumbing, I mean straight plumbing. Ideally, the pipe comes out of the filter, 90’s down to the ground, and runs straight in and out of the heat pump, which has connections that are at the base of the unit. After coming out of the heat pump, the pipe connects before a pool return valve.
Chlorinators should be installed after the heat pump, with a check valve installed between them, to prevent chlorinator back-ups.
If you are replacing a gas heater with a heat pump, the pipes enter and exit at a much higher level. No matter, cut the pipe back and plumb new pipes, closer to the ground, using as few 90’s as possible. For the exit pipe, you may want to lower your return valves closer to the ground, or use a 45° fitting to raise the pipe back up to meet the return valve height.
Pool heat pumps come with union attachments, so you can easily disconnect it and drain the heat pump for winterizing.
Heat pumps require a dedicated circuit with a fairly large circuit breaker. Depending on the heat pump size, it will need a 30 to 50 amp breaker.
If you have a 100 amp sub-panel breaker box at your pool equipment pad, as many inground pools do, add up the amps (printed on the existing breakers), and see if you have room to add a 30, 40 or 50 amp breaker, and still be under 100 amps. If not, the circuit can be upgraded by an electrician to bring more power out to a larger sub-panel, or run a dedicated line to the heat pump from the main panel.
Besides bringing in power to run the heat pump, there could be wiring for freeze control sensors, or integrating to a controller system, if you have one. Heat pumps should be bonded according to local codes. An electrician is recommended for a heat pump installation, or at least the last of the 4-P’s, the other items you can do yourself!
A heat pump may cost more to install than a gas heater with a nearby gas meter, but it will heat the pool for much less than any other pool heating method.
How much less? In ideal conditions, as much as 70% less – as this chart illustrates, the cost to generate 1 million BTU’s with various pool heating methods.
Visit our Heat Pump section to compare a huge selection of pool heat pumps.
InTheSwim Blog Editor