Heat Pumps - post here.

I only log one item to feed for each input

My system - https://emoncms.org/app/view?name=championc&readkey=5e5a2bd11d69740be46a55e1793e551d

So the sensor was in the sun for just over an hour, so not the worst I suppose

Hi all.

What are peoples thoughts on Mitsubishi Heatpumps (Ecodan R290). I got a quote for supply and install of an 8kw unit and 5 replacement radiators for around €15k

Thanks

What are the best for radiators?

While I get that the UFH surface is likely far larger than that of the the rads, I don't think the system water temperature needs to be massively higher than that needed for UFH

I have all rads, and my flow temp a month ago was mid 30's

My SCOP is 4.38

I have a question for a samsung heat pump, i saw advice to get better efficiency you can lower the heat curve to -2degC, and check if that still gets the room up to temp. Can anyone tell me what that setting is called on the samsung/ kodiak system?

Not sure what you mean, but it's all about having the temperature as low as possible to replace the heat being lost.

The norm is to take and set the temperatures for the curve at +15 and -5 outdoor temperatures

Use this graph to select temperatures. If your house is well insulated, then I would start with the temps along the 0.6 line, and lower once per day. If you feel chilly, then bump back up a notch

It really depends on how accurately sized the heatpump was for your house. If oversized, then on an average day, the heatpump could use that alone.

You need to look at power consumption stats on the heatpump.

My 5kW was possibly using around 10kWh in Autumn and Spring. My SCOP is 4.38

Thanks @championc

I am looking at installing an 8kw heat pump so was just wondering if anyone had a similar experience really.

Contractor has said that the calculated heatloss for my house is 7.7kw

In the dead of the winter a heatpump could use 30-35 units in a day. On average 16kwh should cover you most days but I'd say Dec to Feb you wouldn't

Yes. Think my highest day was about 22kWh this year. Most were in the mid teens in Jan and Feb.

Hgely dependent on getting a heat curve dialed in

I'm in the early stages of heat pump knowledge gathering with a view to getting a A2W to replace our current oil boiler.

I also want to replace windows and back sliding door.

My question is, should I do the windows first before the heat pump? This seems an obvious yes but is it a deal breaker to not do it ?

Windows are double glazed, 20 odd years old.

BER is A3, it was B3 until solar was installed.

Ok, good to know it's not a deal breaker.

I'm sure that it is an easier choice from oil to A2W than gas to A2W, and the initial consideration must be the cost per kWh.

If gas is only 10c and electricity is 30c, then even with a COP of 3.5, the savings are negligible.

Replacing windows will reduce the heat required, so you should be aggressive with sizing a heatpump on the basis that things will only get better. You don't want to size it for the double glazing and then make a change leaving the heatpump oversized.

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