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Heat Pump Swimming Pool Heaters
May 29, 2012 - 1:49pm
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How a heat pump works.
How They Work
Heat pumps use electricity to capture heat and move it from one place to another. They don't
generate heat.
As the pool pump circulates the swimming pool's water, the water drawn from the pool passes
through a filter and the heat pump heater. The heat pump heater has a fan that draws in the
outside air and directs it over the evaporator coil. Liquid refrigerant within the evaporator coil
absorbs the heat from the outside air and becomes a gas. The warm gas in the coil then passes
through the compressor. The compressor increases the heat, creating a very hot gas that then
passes through the condenser. The condenser transfers the heat from the hot gas to the cooler
pool water circulating through the heater. The heated water then returns to the pool. The hot gas,
as it flows through the condenser coil, returns to liquid form and back to the evaporator, where
the whole process begins again.
Higher efficiency heat pump pool heaters usually use scroll compressors versus the reciprocal
compressors of standard units.
Heat pump pool heaters work efficiently as long as the outside temperature remains above the
45ºF–50ºF range. The cooler the outside air they draw in, the more energy they use. However,
since most people use outdoor swimming pools during warm and mild weather, this usually isn't
an issue.
Selecting a Heat Pump Pool Heater
Heat pump pool heaters cost more than gas pool heaters, but they typically have much lower
annual operating costs because of their higher efficiencies. With proper maintenance, heat pump
pool heaters typically last longer than gas pool heaters. Therefore, you'll save more money in the
long run.
When selecting a heat pump pool heater, you should consider its:
Size
Efficiency
Costs.
Sizing a Heat Pump Pool Heater
You should have a trained pool professional perform a proper sizing analysis for your specific
swimming pool to determine pool heater size.
Sizing a heat pump pool heater involves many factors. Basically, a heater is sized according to
the surface area of the pool and the difference between the pool and the average air
temperatures. Other factors also affect the heating load for outdoor pools, such as wind
exposure, humidity levels, and cool night temperatures. Therefore, pools located in areas with