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 (

METERSUK.CO.UK "https://metersuk.co.uk/products/single-phase-electric-the-tiny/)"

Meters UK - Utility Sub-meter Manufacturers & Distributors

Meters UK - Sub-metering systems for residential, commercial, or industrial application, as well as remote or online prepayment metering. Contact 01524 555 929.

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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