Heat pump diagram

The Heat Pump is very simple once you understand the basic concept (and I promise you will after reading this). As the name suggests a heat-pump transfers or pumps heat from one place to another, (notice the use of the word “pump”- heat is not generated but rather is moved).

As they say “a picture worth a thousand words”. So let’s see one:

In this Example:

1. The flame heats up the water.
2. The hot water is pumped to the radiator.
3. The fan forces the Cold Air over the Hot Radiator and the air becomes hot.
4. The water becomes cold because the heat has been transferred from the water to the air. The cold water is then pumped back to water tank- where it is heated up again (Step 1).

• Notice in this example that the flame generates the heat. We transfer that heat to the air using a medium (in this case the water) pumped through a radiator. Pumped heat- a heat pump!
• The real heatpump doesn't differ that much from this simple example- we just replace the water with a refrigerant (such as Freon) and replace the water pump with a compressor.

The real Heat Pump in action
Cooling Mode (regular Air Conditioning)

Hold on a minute- Does that mean a regular air conditioner is considered to be a heat pump?

Well let’s see:

1. Heat is generated inside your house- from sun shining through windows and onto the roof and walls, from appliances and from your body. This is the equivalent of the flame heating the water in our first example.
2. Your air conditioner transfers that heat from inside your house to outside your house. This is the equivalent of the pump and radiator

So in theory- yes, any regular air conditioner can be considered to be a heat pump (but don’t tell this to your repair man or you will confuse him!)

So what is different between your regular air conditioner and a heat pump?

Before we discuss the difference let’s see how the heat pump acts in Cooling Mode:

Before we start notice three things:

1. The Direction of the flow of the refrigerant.
2. The inlet and outlet ports of the Compressor (those will never change) Did you notice?

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