Q: Is it ok to turn off my heat pump and MVHR over the summer months?
Ryan says:
I would not recommend switching anything off in the summer months. Most modern heat pumps will have what is called an “outdoor stop” temperature setting. Your installer will normally set this to 16 degrees and when the outside temperature is above this the heating function will not work, and the heat pump will provide hot water only.
So, it is in effect all automated and there is no need to do anything. Also, if any room thermostats are reading a temperature above the setpoint (normal setpoint would be 20 to 21 degrees) the heat pump will not come on anyways on heating mode as the house is heated by solar gain and higher natural ambient outdoor temperatures.
With regard to mechanical ventilation with heat recovery (MVHR) systems, turning it off is not advised as during the evening or early morning the system is still required to remove moisture from wet rooms.
Most systems will have a built-in temperature sensor whereby a summer bypass setting can be set during commissioning. Commissioning is the last step in the installation; it’s when the system settings are set and checks are made to make sure the system is working as it should. When the temperature in the unit is above the setpoint, the system exhaust air will bypass the heat exchanger which reduces the supply air temperature to the habitable rooms during periods of hot weather.
The cost of running the MVHR system is quite low therefore it is better to leave it running 24/7 even if you do open some windows in the summer months, which is okay to do all year round.
