This Ultra Low version means that this heat pump will heat the water of your pool when ambient air temperature is below freezing point (as low as 28F), which will prolong your swimming season. The Electro Heat Ultra Low is part of the Electroheat range from Waterco. Suitable for swimming pools with a surface area over 100m2 they feature the latest advancement in swimming pool heating, Electroheat Heat Pumps are an energy efficient way to heat your swimming pool or spa. ElectroHeat produce up to 5 times more heat energy than the electrical energy it consumes. How a Heat Pump works:- Electroheat extracts heat energy from the surrounding air and transfers the heat energy to the water of the swimming pool. Electroheat works like a reversed air conditioner, using an evaporator, a compressor, and condenser to heat water instead of cooling air. Step 1 Capture The fan circulates air through the outer evaporator air coil that acts as a heat collector and absorbs heat from the ambient air. The liquid refrigerant in the air coil absorbs the available heat in the air transforming it to a gas. Step 2 Transfer The compressor then receives the warmed refrigerant and intensifies the heat. The intensely hot refrigerant is then pumped into the heat exchanger (condenser). Step 3 Heat Exchange The heat from the hot refrigerant flowing inside the heat exchanger is then transferred to the pool water, via the surface of the heat exchanger.s coils. Step 4 The cycle begins again The refrigerant is then ready to restart the process and flows into the evaporator air coil to collect heat again. Low running costs Electroheat will keep your pool water warm 24 hours a day without the need to worry about your energy bills. Age Group: Adult. Material: Other Material.