Ecodan - rubbish data

Air Source Heat Pumps (ASHPs)

Last Post by Gfletcher 3 years ago

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Gfletcher

(@gfletcher)

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Topic starter 18/02/2023 6:28 pm

Hi,

I have an Ecodan 8.5kW ASHP - I have been logging data from the FT6 display (I don't have Melcloud) manually and keeping track of daily household energy use, and the information just doesn't seem to tally. I suppose I shouldn't mind so much, but I would like to understand more accurately how much electricity the unit is using.

An example of the sort of data that is being generated - for January the FT6 is saying that the heatpump consumed 402kWh of electricity for both DHW and heating. The delivered energy was 902 giving a COP of 2.24. My total household energy use was 488kWh for January. Therefore if I take the consumption data that means that on average the heatpump was using 13kWh a day (not unreasonable) and the rest of the house was using 2.8kWh a day (4 bed house with 2 adults working from home and 2 teenagers). The total household energy use is correct - that is what I am billed! Pre-heatpump my average household energy use across the whole year was 5.6kWh a day. Is there anything I can do with my existing setup to improve the accuracy of reporting, or do I need to look at a 3rd party system to record actual use? Any pointers would be helpful.

Cheers

Gavin

This topic was modified 3 years ago by Gfletcher

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HarriUp

(@harriup)

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18/02/2023 7:38 pm

Yep, the self-measurement of the Ecodans is highly inaccurate. For January mine gives me a consumed estimate of 687kWh against a metered value 631kWh.

If you want an accurate value you'll need a meter on the supply circuit. It will depend how much you are happy to intervene in the the wiring arrangements. A straight forward meter inserted into the supply circuit ( https://metersuk.co.uk/products/single-phase-electric-the-tiny/) will give you an accurate record but one that you will have to read yourself as and when. I have my circuit wired through an Eastron SDM120 meter mounted next to the consumer unit which then feeds a value into an OpenEnergyMonitor setup which records and displays the energy consumed via computer/phone. If you don't want to rewire the mains at all you could go with a CT clamp-based arrangement where a circular magnet is clamped around the live wire inside the consumer unit (eg https://metersuk.co.uk/products/single-phase-electric-meter/).

Mitsubishi EcoDan 8.5 kW ASHP - radiators on a single loop
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Gfletcher

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