New to the world of heat pumps - help and advice needed
Hello, my first post here having just found the site today We had a Grant Aerona 3 ASHP installed about 4 months ago on an ECO4 grant. We are far from happy with the performance. The original installation wasn't a very well done job. I've had a guy back from the installer company yesterday doing all sorts of checks, but today, after 12 hours running, out of elevan radiators only two are over 30 deg C. I appreciate they dont get as hot as they would from our previoius combi boiler, and they were all changed for double units, but what sort of temperature should I expect? I would have thought about 45 deg C? If i fail to get any resolution from the installer, what recourse do I have and are there any independent bodies I can contact to take a look at the system and see what might or might not be wrong with it? PS..just ordered the book Bodge Busters..that looks useful! We had absolutely no training or demonstration on how it all works. One team fitted all the hardware, a few days later an electrician came and wired it all up but at no time did anybody do a commissioning check. Any advice gratefully appreciated!

First things first, @wesleyp1874, welcome to the forum. You’re right that there are a lot of members here with a wealth of broad knowledge and experience and a willingness to help. There are also plenty of members who have had less than ideal initial installations and had to learn on their feet to get things sorted; you’re not alone and there is a lot that could be done.
One thing I notice, though, is that you’re judging the performance on the heat of the radiators and that may not be the best way of identifying any problems. In essence, you don’t want warm radiators, you want a warm house. If the rooms are warm enough, the radiators are doing their job. Of course, if your installers have left you with a system that doesn’t keep the house at a constant comfortable temperature then presenting them with room temperature data leaves them with no wiggle room to argue technicalities.
Are you able to get some readings of how warm your rooms are (and what you want them to be)?
It’s late as I write this so I’ll comment more on the other issues tomorrow.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
Thanks for your reply. The thermostat (EPH Controls) is in our hallway that has three new double panel radiators in it, and has been insulated. The heating came on at 7am, currently showing 15 deg C. The only way we get to anything like 20 deg C is lighting the log burner as well! I've just ordered a digital room thermometer with a recording app so I can keep a constant check on temperatures.

Posted by: @wesleyp1874Hello, my first post here having just found the site today We had a Grant Aerona 3 ASHP installed about 4 months ago on an ECO4 grant. We are far from happy with the performance. The original installation wasn't a very well done job. I've had a guy back from the installer company yesterday doing all sorts of checks, but today, after 12 hours running, out of elevan radiators only two are over 30 deg C. I appreciate they dont get as hot as they would from our previoius combi boiler, and they were all changed for double units, but what sort of temperature should I expect? I would have thought about 45 deg C? If i fail to get any resolution from the installer, what recourse do I have and are there any independent bodies I can contact to take a look at the system and see what might or might not be wrong with it? PS..just ordered the book Bodge Busters..that looks useful! We had absolutely no training or demonstration on how it all works. One team fitted all the hardware, a few days later an electrician came and wired it all up but at no time did anybody do a commissioning check. Any advice gratefully appreciated!
OK, I've had a bit more of a think about your post so I can reply in a bit more detail.
I don't know much about the ECO4 scheme but there are quite a few threads on the forum discussing aspects of it. I believe one member (@lenny) had a successful ECO4 heat pump installation whilst also having things that needed tweaking, hence potentially useful experience to bring to your question. In fact, one post I found from @lenny raised one of the same criticisms you have made in that the work was carried out by quite a lot of subcontractors with less cross-communication than would have been ideal. I also believe one of our fairly long-standing members - @bontwoody - did a fair bit of fact-gathering on behalf of a friend who was looking into the ECO4 scheme, so he may well be able to give more insights.
Getting a copy of the Bodge Busters book is a good move, since arming yourself with knowledge of how things should operate is invaluable when talking with installers about problems. I would also suggest you take a quick look at one of the recent articles posted on this forum - The ABCs of ASHPs: A Jargon-Free Introduction to Heat Pump Basics - Renewable Heating Hub. This article may even be a little too basic for you now but I suspect will still be useful in filling in some gaps so you have a broad foundation of understanding.
The key, though, seems to me to be understanding exactly what isn't right and getting that tackled, and that means being targeted and accurate in what you're complaining about. Eventually, a heat pump is there to provide you with a warm house and hot water at a reasonable cost, and if it fails in any of those three areas then it is patently not performing as it should. As I mentioned in my previous post, giving you warm radiators is a distraction despite the apparent relevance, so is not a good foundation for tackling an installer on. As an aside, you asked what temperature radiators could be expected to get to and that's hugely dependent on each case but in my house the water leaving the heat pump at the moment is at 27degC so obviously no emitters in my house will be warmer than that.
In your position, I would start with personal comfort and measure the temperature of several areas in your house to see if they are and remain at the right temperature for you. Secondly, I'd do the same with the hot water; are you being supplied with a tank of water at about 45-50degC so you can take hot showers and baths and so on? Thirdly, I'd look to how easily the heat pump is coping with doing all that and that means measuring energy being used vs energy being pumped into your house (the Coefficient Of Performance discussed in the ABCs article).
Of course, the COP is only a measure of technical efficiency, not practical performance. If your home and hot water are warm enough and the heat pump is managing a COP of about 3.5 or above, but the actual cost of the electricity used is high, it may be your heat pump is really efficiently heating your garden (i.e. your house's insulation may not be up to scratch and so you need to get a different ECO4 subcontractor back or the pipework from your heat pump is not well lagged and so your HP installer needs to correct that) or you may be wasting energy elsewhere. Either way, you gathering the basic ammunition I mentioned and you doing a bit of learning as you have patently already decided means you are well placed to tackle your installers without having the wool pulled over your eyes. And if they give you some spiel you don't understand then the rest of us here are happy to help with advice.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"

Posted by: @wesleyp1874Thanks for your reply. The thermostat (EPH Controls) is in our hallway that has three new double panel radiators in it, and has been insulated. The heating came on at 7am, currently showing 15 deg C. The only way we get to anything like 20 deg C is lighting the log burner as well! I've just ordered a digital room thermometer with a recording app so I can keep a constant check on temperatures.
Your reply came in whilst I was typing.
One of the first things to consider is not turning the heating off overnight; a setback to a slightly lower temperature is OK if you find it's easier to sleep like that but from the heat pump's point of view it would prefer to be keeping the house at a constant temperature 24/7. It would be interesting to see if it then does get to and remain at 20degC, although from what you describe it sounds as if the heat pump is struggling nonetheless. Nonetheless, well worth giving it the best chance.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
@wesleyp1874 I seen a few ECO4 installations now and it really is pot luck. As you say a lot of the work is often subcontracted and how well that is managed is very variable. The good news is that even if your system hasnt been set up well, the bones of the system and house are likely to be right and very suitable for a heat pump.
As the Major says, the temperature of the radiators isnt really an indicator of much, its how warm the rooms are that matters. Do you know if your system has been set to run on Weather compensation? It should have been. If it has and you can determine the settings, that would be very helpful in trying to determine whats going on. Also some details on the size of your house and the heat pump would help.
House-2 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
Again many thanks for all the info, a lot to be going on. I did hear the guy who was working on it on Monday mention a weather compensation curve. Still something I need to learn about! We live in a late 18oos stone built chapel, Quite aedequately heated by the Baxi combi gas boiler we had removed when the heat pump went in. Evenb after a lot of insulation work, we dont feel as warm as we did in this cold weather we have had the last few weeks. The heat pump is a Grant Aerona 3 13kw. What thoughts do people have about microbore pipework? I had concerns about that as it comes up through the floor onto the rads as microbore. I was told it would be changed if necessary but the team doing the installation said it didnt need changing. A towel rail in the upstairs bathroom is still on standard 15mm pipework coming out of the wall but it does not feel any warmer. Thanks
@wesleyp1874 The microbore wont change the temperature of the radiator, but it could mean that you have to run the heating water hotter than if larger pipes were present. My house is mid 1800's and the older walls are not insulated so its perfectly possible to be comfortable in that setup with a heat pump. There isnt any obvious reason why you should be cool unless the weather compensation curve is too low. Increasing it will make it warmer but at a cost of increasing bills.
The pipe diameter puts a limit on how much heat can be supplied to the radiator.
House-2 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
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