Heat Pump Specialist

This module contains some slightly more advanced knowledge, and practical "how-to" sections on a variety of subjects. It's intended for information only, so there are no assessment questions. If there is anything you would like to see included here, please let us know!


Cooling with a ground source heat pump

Can it be done? How?

What about MCS and RHI?

How to: repressurise the ground array (for homeowners)

make a little video! do one for the system too.

Wiring, Controls and Weather Compensation

What controls can I fit?

Do Kensa units have weather compensation?

Wiring diagrams

Electrical phases and start-up currents


Start-up current and soft-starts

Heat pump fault codes and their meanings

Fault codes

Other codes

Blank display

How to: Commission a heat pump

Getting started



Switching the heat pump on

Check for air in the pumps

Change the antifreeze alarm setpoint

Change the heating return temperature setpoint

Switch on the compressor

Take sensor readings ("b readings")

Enable weather compensation (optional)

How to: Diagnose common system faults

The hot water is not very warm

The heating is not very warm

The heating does not come on at all

My electricity bills are very high

How to: Fill, flush and purge a ground array

First - de-air the array

Pressure testing

Add the glycol

Pressurise the system

Sizing for water source

Some hints on open loop - flow rates andheat exchangers.

Controls and permissions

Metering for heat pumps

Do I need a meter?

What meter?

Where does it go?

Useful links

Unusual system configurations

More than one hot water cylinder

More than one heat pump

Low loss headers

Multiple heat sources