How does heat pump water heater efficiency work?

heat pump water heater efficiency

How does heat pump water heater efficiency work?

Heat pump water heater efficiency has resulted in our planet being spared billions of pounds of additional greenhouse gases. But how does this technology work?

Have you ever wondered why warm air comes out from underneath your fridge? The reason for this is that a fridge uses heat pump technology to move heat from the inside of the fridge and then expels it outside. In the same way, a heat pump air conditioner finds heat in the outdoor air and then moves it indoors.

Heat pump water heater efficiency is as a result of the same technology, which removes heat from the ambient air around it and expels it inside a tank of water. In essence, it’s an air conditioner in reverse.

The process is made possible by a compressor and a substance called refrigerant. Inside the water tank is a coil of piping that extends out of the tank, to and from a compressor. The refrigerant inside the piping is compressed and heated by the compressor as it is forced into the inlet pipe, where it condenses and gives its heat off to the water.

The cooled refrigerant then leaves the tank via the outlet pipe and passes through an expansion valve, which then repeats the process by sending it back to the compressor.

Heat pump water heater efficiency is improved if the ambient air around the heater is already warm. Therefore, in warmer climates, the best place to install a heater is in an unconditioned garage, or a utility room if it has sufficient ventilation.

In contrast, standard water heaters use inefficient, energy guzzling resistance elements to heat water, just like a water kettle. The only advantage that resistance water heaters have compared to heat pumps is their speed of heat recovery. It takes longer for a heat pump to reheat a tank of water. For this reason, hot water usage has to be managed. However, for those occasions when an increase in hot water supply is necessary, a hybrid water heater includes backup resistance elements to take up the slack and maintain an interrupted flow of hot water.

Thanks to heat pump water heater efficiency hybrid water heaters limit the production of electricity and, as a result, reduce the amount of greenhouse gases entering our atmosphere.

Please continue reading my Heat Pump Water Heater – 3 product review and visit my Hybrid Water Heaters Store. Also see my other review posts for this green living product: 

Eight best features of heat pump water heaters.

Ten reasons why a Heat Pump Water Heater is green.

Heat Pump Water Heater FAQs.

Tips and Tricks for Heat Pump Water Heaters.

Heat pump water heater efficiency – how it works.

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