What is the difference between an inverter heat pump air conditioner and a conventional one?

Sunday, June 17, 2018

Converts AC To DC And Runs Continuously

The compressor inside the outdoor condenser unit of a conventional heat pump runs on regular house alternating current (AC). It turns on when it receives a signal from the thermostat, and runs at full speed until the desired temperature is reached. Then the compressor shuts down until a difference in the indoor temperature requires it to start up again on a new cycle.

    An inverter heat pump does things differently. It converts the single-phase AC to direct current (DC), then reconstitutes the DC back to AC current in three-phase format, and varies the voltage and frequency of the current to modulate the speed of the compressor. 

    The lifespan of an electric motor is measured by the number of on/off cycles, not the length of run time, so reducing the number of cycles extends the life of the system. An inverter compressor accomplishes this feat by running continuously and simply slowing down as the indoor temperature approaches the desired set point.

   Also, running continuously eliminates the large surge of electricity necessary to overcome inertia each time a conventional compressor starts up. This saves on electricity. 

Improved Dehumidification

    A secondary function of a heat pump system is dehumidification, and yet another feature of an inverter is that it improves the dehumidification of a home by continuously removing moisture from the air. A regular system would over-cool if it ran constantly to dehumidify.

   Inverter heat pumps do have a single disadvantage: they are new technology and, of course, more expensive.

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  To learn more about heating and air conditioning systems, see these other blog posts:

How can I find out the SEER of my air conditioner? 

My air conditioner won't turn on. What's wrong? 

How can I find out the size of my air conditioner? 

How can I tell whether the condenser (outdoor unit) is an air conditioner or heat pump? 

Where is the air filter for my central air conditioner and furnace? I can’t find it? 

Does an old air conditioner use more electricity as it ages? 

How did homes stay cool in Florida before air conditioning? 

What is wrong with an air conditioner when the air flow out of the vents is low?

Why has the thermostat screen gone blank? 

Why does it take so long to cool a house when an air conditioner has been off for a while? 

Why is my air conditioner not cooling enough? 

What are the most common problems with wall/window air conditioners?  

Will closing doors reduce my heating and cooling costs? 

   Visit our HEATING AND AIR CONDITIONING page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles. 

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