14kW Ecodan system installed in a 370sqm new build - Air Source Heat Pumps (ASHPs)

RE: 14kW Ecodan system installed in a 370sqm new build

HJD — Sun, 21 Nov 2021 08:14:54 +0000

@derek-m I am fairly pleased with a CH COP of 3.7 under this new 'weather compensation' approach. I looked at last year's data, when the ASHP was relying on the zoned room thermostats only, and for 2020 I only achieved an equivalent COP of 2.7.

ON DHW - we have it set at 48deg which is a reasonable balance, for us, between hot water from the tap and energy efficiency. We tried both timed and immediate reheat approaches and found that immediate reheat was more energy efficient (just).

Definitely send me the spreadsheet when you have it. Thx

RE: 14kW Ecodan system installed in a 370sqm new build

Derek M — Thu, 18 Nov 2021 17:45:09 +0000

Posted by: @hjd

@derek-m Indeed - definitely a D- for effort!

I calculated the COP on the Central Heating which is running at 3.7. The DHW is much worse - around 1.6

Hi Howard,

We will let you off this time, just don't do it again. 😎

A Cop of 3.7 seems quite good, though it may be possible to improve this. Producing DHW is always going to have a lower COP because of the higher water flow temperature required. What is the desired temperature setting for your DHW?

You may have read in one of my earlier posts today that I am developing a spreadsheet which models an Ecodan based system. Since you have the same model as Kev (who supplied the Ecodan data), you may also find it of use.

RE: 14kW Ecodan system installed in a 370sqm new build

HJD — Thu, 18 Nov 2021 17:15:58 +0000

@derek-m Indeed - definitely a D- for effort!

I calculated the COP on the Central Heating which is running at 3.7. The DHW is much worse - around 1.6

RE: 14kW Ecodan system installed in a 370sqm new build

batalto — Mon, 15 Nov 2021 18:25:34 +0000

@hjd we are very similar. I have a 12kw Midea unit and my floor space is 262m2

RE: 14kW Ecodan system installed in a 370sqm new build

Derek M — Mon, 15 Nov 2021 18:09:18 +0000

Posted by: @hjd

Hi all thanks for the comments. Before everyone leaps to conclusions about the amazing performance I have to admit to a typing error at 7am this morning....its actually 270sqm rather than 370sqm! Which makes the stats less impressive!

Sorry Howard, you only get 5/10 for personal performance, 'must pay attention to detail'. 😉 But your systems performance is still very good, even with your smaller property.

You can obtained data for energy used and energy produced from your FTC controller, which will allow you to calculate your ASHP's Coefficient of Performance (COP), which is a measure of how efficient your system is operating. If you are not certain how to obtain this data, there are a number of videos on the internet, or you could ask one of the friendly forum members.

RE: 14kW Ecodan system installed in a 370sqm new build

HJD — Mon, 15 Nov 2021 17:44:40 +0000

Hi all thanks for the comments. Before everyone leaps to conclusions about the amazing performance I have to admit to a typing error at 7am this morning....its actually 270sqm rather than 370sqm! Which makes the stats less impressive!

RE: 14kW Ecodan system installed in a 370sqm new build

Derek M — Mon, 15 Nov 2021 10:22:53 +0000

Posted by: @hjd

@siko Good question. We didn't specify it so not entirely sure who did the calcs. That said, for 7-8 months a year it only has to deal with hot water. For the remaining 4/5 it is dealing with heating as well. In recent weeks - and it has been fairly mild - we have been running at about 10-12KWh per day on heating. Not sure if that is good or bad really!

Hi Howard,

12kWh for a large property is very good. Do you have any heat loss calculations for your property? Where is your location?

Have you considered a solar PV system to both help power your ASHP or help provide hot water from Spring through to Autumn?

RE: 14kW Ecodan system installed in a 370sqm new build

siko — Mon, 15 Nov 2021 10:00:26 +0000

That seems really good, I must admit I don't know what the separate usage is for ours but we are very heavy users of electric and our total usage (water, heat, light, power etc etc) was 843kwh in Oct, probably on track for 1000+ in Nov. So we average prob 30 kwh a day for everything...again I don't know if that is good or not, but compared to before the ASHP came our bills are only marginally higher.....so far!

RE: 14kW Ecodan system installed in a 370sqm new build

HJD — Mon, 15 Nov 2021 09:57:08 +0000

@siko Good question. We didn't specify it so not entirely sure who did the calcs. That said, for 7-8 months a year it only has to deal with hot water. For the remaining 4/5 it is dealing with heating as well. In recent weeks - and it has been fairly mild - we have been running at about 10-12KWh per day on heating. Not sure if that is good or bad really!

RE: 14kW Ecodan system installed in a 370sqm new build

Jeff — Mon, 15 Nov 2021 09:50:32 +0000

Posted by: @hjd

@kev-m Thank you for sharing your experience and recommendations. I may have to get acquainted with the dip switches!

Recent video of someone installing the wireless device in case it is useful in any way.

https://youtu.be/hWPdFPWEpJc