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I monitor all my existing systems using kit from the OpenEnergyMonitor people and it works really well.

Just in the process of getting a quote for an ASHP install (which I'll almost certainly accept and go with) and need to know what sort of kit is best to monitor such a thing as I assume things such as heat meters (if necessary) would be better installed from the get go rather than as an afterthought.

I don't need the meter for RHI etc - I'm using the new grant to subsidise the installation - but for monitoring COP etc.

Outputs need to be mbus or some other easy to read standard I assume to be able to link to the existing monitoring kit.

Thoughts?

greentangerine wrote: ↑Thu Jul 14, 2022 11:02 am I monitor all my existing systems using kit from the OpenEnergyMonitor people and it works really well.

Just in the process of getting a quote for an ASHP install (which I'll almost certainly accept and go with) and need to know what sort of kit is best to monitor such a thing as I assume things such as heat meters (if necessary) would be better installed from the get go rather than as an afterthought.

I don't need the meter for RHI etc - I'm using the new grant to subsidise the installation - but for monitoring COP etc.

Outputs need to be mbus or some other easy to read standard I assume to be able to link to the existing monitoring kit.

Thoughts?

I haven't bothered with a heat meter. I was able to go into the installer menu of my NIBE and run the heat pump using the immersion ( at a known power setting) at various pump speeds. I let the delta T stabilise at 5% increments on the pump speed.

I then monitor the pump via Modbus which also gives me the power input and pump speed as it modulates. It is then possible to calculate the power output and therefore the COP. It seems to give very sensible readings and saved a lot of money.

At each pump speed record the value for [immersion power in]/dT. I needed a separate set of values for the DHW and radiator circuit. This requires all the radiators to be a set setting rather than all opening and closing.

Then to get power out just interpolate the values you recorded for the current pump speed. Then multiply this by the power In. Then you can calculate COP as (estimatedPowerOut-currentInternalPower)/(current internal power)