Are Circulation pumps included in the COP figure?

Hi! All,
I am a bit new to this monitoring and wondered if the Circulation pumps are included in the COP calculation? I notice that the pumps are using about 250w when the Heatpump is cycled off by the flow temperature. I have also thought that the Crankcase heater is using power when the Heatpump is in the off period of the year so is this included as well for the COP and the SCOP?
Any thoughts are most welcome.

Hi Bob, welcome to the forum.

It depends if the pumps are wired into the electric meter or not.

IMHO, it’s best to include them if possible, so that you’re seeing the performance of the whole system, including standby.

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Hi! Tim,

Thank you for your reply and warm welcome.
Currently the pumps and the crankcase heater are all run from the same feed that is metered by the monitoring system, so, all power used by the heatpump system is included. However. The circulation pumps used by the underfloor heating are separate as these are used if the gas boiler is in use or the Heatpump is in use.
I am guessing most other systems being monitored include the Circulation pumps for the heatpump in the COP figures. So I am looking at this correctly?

I can see it would be tricky to include the pumps for the underfloor heating, so these just might have to be outside of the heat pump metering. There may be some clever metering tricks that someone can think of to ensure the consumption of the pumps is only considered when the heat pump is on, but I’m not sure it’s worthwhile.

Most systems do include the circulation pumps, but not all. Looking at 75 systems listed on, only 47 of them (63%) are noted to include circulation pumps. Now, we’re not sure how accurate this information is, but it gives you an idea of how other systems are measured.

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