Heat Pumps - post here.

The offset value is set at 2c, but is not applied.

Use this graph to set the points at +15ish and the -5ish ends of any heat curve. Focus more on the black line below the red line.

I have turned off the programme in the thermostats and set the temp on them to 30deg so I presume they are just calling for heat and the weather curve will do its thing and drive the temp. once I know what its currently doing I can then start the dial back.

I might set some thermometers for rooms.

If the 45 is too high I should I see the temperatures push past 22 ya? I think it doing 40deg now when it is 6 outside.

I have radiators upstairs and down. Is 45 more in line for them?

Thats the top of my weather compensation.

Interesting. I don't know what "a ads" is though? Is that how you pull the data? Am I reading that right 40kwh a day or so on heating? Seems a lot!

@Jo Satan I ran it overnight with the thermostats maxed but didnt adjust the weater compensation profile, seemed to get rooms up to about 22 degrees and was constantly cycling looking at the energy profile. I thought it might go higher.

I went to adjust the profile this morning and brought the 45 down to 40. However it looks like the lowest I can go for the low temp is 35degrees. I not you are at 20degrees. That a big difference! Any idea why?

My low outside temp is 0, not -3 as you thought it might be. The text is just not centred.

Do you have under floor heating?

We are in a 2006 upgraded bungalow, HLI 1.785, all steel rads. No internal temp control and purely run on weather compensation. I do have stats in all the rooms to monitor temp etc. and this maintains a temp of approx. 20°C, there is probably a fluctuation of +/- 0.3°C

This is our weather curve with the max temp set on the heat pump of 40°C

These are readings showing the flow temps, power used, outside temp and the daily power amount used over the last three days, when we had a mix of fairly mild with Sat being a cold day/night. The spikes are when heating the water or running a defrost cycle.

thats hard to answer.. you will need to know the heatloss of your property. Your rads might be too small to use with a heatpump. If they need replacing will add to the cost. If you dont need hot water (what about handwashing/sink/dishes?) I know champion uses his system only for space heating. From what ive been told typically its around 12-16k with few rads replaced, hot water cylinder & heatpump installed but at lot depends on your requirements. Only an installer who can do a heatloss calc for you and size rads etc can give you a proper answer.

yeah im not far off novice level myself.. the challenge with heatpumps is to get them running optimally careful calcs need to be done for heating requirements. You probably know this but the idea is your run your rads at approx half the temp of a gas/oil boiler leaving them on pretty much all the time.. this slow and low heat heats your property consistently over time.. if you put a heatpump in thats to large and it cant modulate down it will use more power than you need to provide the heat.. if your rads arent big enough it will need to run harder to provide the heat.. if your pump is sized to small it will never get your property up to temp so will also use more power.. its not a complete mystery but if looking for installers the first conversation should be about heatloss and they should be looking for your most recent ber report if you have one, heat loss indicator.. or if not available a technical assessment should be done etc.. no one should be quoting you for an install without at least a site visit to check out the property and doing some calcs for your requirements.

When looking at heat pumps and BER's the more important figure is the HLI, the lower the better.

For the grant and homes built before 2007 this needs to be 2.3 W/(K.m2) or lower, from 2007 onwards it is assumed that this will be the case.

You could have a G rated house and stick enough solar panels on to get an A rating, this will not alter the fact that it will leak heat like a sieve.

How do you get this info? Does your heat pump have an app?

@Grey123 should have said RADS.

From the data, the 40kWh is the HEAT, delivered from less than 10kWh of power. On the graphs, blue is power and orange is heat energy

As for adjusting the heat curve, you have to consider both ends of the slope. You may not have been able to lower one end further if the other end was still higher

Have you a buffer tank ?

100% - Ive been doing this for 8 years and it works like a dream. Slight tweak needed when we get to minus temps. Very low annual bill for 2800 sqft house. It really does help if you have an APP connected to your HP to simplify schedule etc

Here is my energy use for the day. From 2am to 4am the hot water tank was doing its thing.

My EV was charging from 4am to 8am.

The overnight spikes are approx every 30min. However I dropped the top of the curve from 45deg to 40deg at 9am and the spike (pump runs I guess?) have become more frequent, that doesn't look very efficient or good for the pump, they are probable every 15min.