[Sticky] Say hello and introduce yourself
@transparent Thanks for the advice. I'll consider the points you've highlighted on photo and get back to you.
@transparent I don't understand how these kind of loft installs can ever pass muster from an insulation point of view. its basically outside!
@noburn I'd be tempted to think about ways to build additional insulation (celotex boards or similar) in an enclosure around the whole thing, to alleviate heat loss to the outside. Also for those uninsulated valves, diy fitting of pipe insulation is easy. With a knife and gaffer tape you can make it fit around most valve fittings. 28mm which is what they'll have used for the pipes, as a size is really too narrow for valves (which is probably why they didn't do it) but can be done with patience and a lot of cutting. wider stuff (35mm, 42mm) will fit more easily around valves.
about the system, the thing I noticed was that you have 3 circulating pumps. which is a bit of a puzzle. If you have time, it'd be worth drawing up a system diagram of what is connected to what. just boxes for components and lines for pipes. if you are trying to troubleshoot it or optimise performance at any point, this will be invaluable. I'll counter @transparent's comment on DHW - you don't need it at 50, and heating to 40-something is more efficient in a direct comparison. But if you find that a tank at a higher temp allows you to get through a days usage with one reheat, and the lower temp doesn't, the higher temp may be more efficient (either in money or energy terms) than reheating more than once to a lower temp. This is something thats always specific to the HW usage pattern of the residents, electricity tariffs etc.
@iancalderbank I was thinking of building mine an insulated cupboard in the loft so interesting you said that as was my first thought when mine had to be put in loft.
@joti yep you can't over insulate. my cylinder and all the complex pipework are inside the main body of the house, but some of my primary pipework has to pass through an uninsulated loft space. They have pipe insulation (with lots of carefully trimmed bits around the valves on them), but they also have 2x 150mm of loft insulation roll laid over the top of the insulated pipework. Its easy DIY.
@iancalderbank I'm stillwaiting for my loft to be insulated, long story but logic tells me exactly that so will be doing something eventually. Heat loss was noticeable when my tank had to be moved to the loft.
I don't understand how these kind of loft installs can ever pass muster from an insulation point of view.
I think this ASHP installation passes the regulations in the same way that all the others don't. 😥
A couple of weeks ago, an MCS accredited installer told me that they receive an annual inspection of an installation selected at random from a list of their customers.
I have no idea how that's carried out however.
If MCS only check the aspects which fall within their remit, then the efficiency and levels of insulation won't be evaluated.
There's no requirement for a heat pump to achieve any particular COP,
and the insulation falls within Part-L of the Building Regs. That's outside what MCS have responsibility for.
But hey... what do I know?
I have no credentials to approve what's worthy of an MCS pass.
It's their accredited installers who are 'certified'.
it'd be worth drawing up a system diagram of what is connected to what.
Would that be the system diagram which all installers are required to create, and then leave with the customer in order to comply with Building Regs? 😧
Save energy... recycle electrons!
@transparent Re your previous comments:
50 C DHW - I am experimenting with lower DHW temperatures to assess impact.
The cables you identify as needing clipping consist of a) part of my existing solar PV system that had to be moved to allow installation of heat pump system, b) old unconnected and not used cable that originally powered loft lighting, and c) flexible cable to loft light. None part of heat pump system. The various cables on the side of the cylinder could perhaps be tidied up a bit with cable ties.
I intend to improve the insulation of the various valves etc.
@iancalderbank Thanks for suggestions on insulation of valves etc. I intend to add further insulation at some point.
Re the why are
there three pumps question. See attached photo of cylinder during installation phase.
I very much agree with you tackling the pipe insulation yourself.
There are times like this when it isn't worthwhile trying to pressurize the installer to get it right.
There's a good range of pipe insulation available from BES under the Kaiman brand.
I prefer the Class-O insulation. You can find this elsewhere under the Armaflex brand.
BES stock lengths with a bore of 40mm - 56mm, which will probably cope with your valves.
Glue the edges and joins with an impact adhesive.
The exterior pipe insulation must be UV-resistant.
It's listed separately under the title "solar pipe insulation".
Seal all joins with adhesive-backed insulation tape, and use the same tape to prevent rain entering between pipe and insulation where it enters the back of the external fan unit.
Save energy... recycle electrons!
Hello! Introducing myself (and my setup):
I'm self-building a house in west Wales and had a Grant Aerona 3 (10kw) and a 300lt grant pre-plumbed tank installed and commissioned last February.
Generally very pleased with it: there were some small installer issues initially (i had to point out to them that they'd forgotten to fit a circulation pump, and that they'd fitted the expansion vessel on the wrong side of the check-valve), but spent the spring tweaking settings and working out how best to run it, and continued this autumn. Having downloaded the Chofu manual i experimented with running it in reverse during the hot june weather.
I had already installed UFH with a HP in mind, and there might be a plan for blown air heating upstairs, but once all the insulation is in i suspect that will be more useful for cooling in the summer,
Only other relevant info you might want is that i set up a small off-grid electrical system here when i moved in 11 yrs ago (before all these off-the-shelf hybrid inverters and batteries were widely available), incorporating 5000w pv, 400w hydro-electric, and a small 24v battery hooked up to a powerjack inverter (with the hydro, you can get away with a small battery - at least until you get a heat pump). I do have a grid connection (with octopus) via a changeover switch, but try to use only homeqrown leccy.
Good evening,it's really good to see a community of people prepared to share their journey with heat pumps etc and not try to sell you something! Well done for setting it up and moderating.
I am currently trying to get some info together about our ashp and ask for advise from members but it may take me a while to collect it.I'm not at all technical so I'm afraid alot of the language goes over my head, not helped by having almost zero handover from the installers.
@alisonp, welcome to the forums. When you're ready, start a dedicate topic focusing on your home and requirements.
@editor Hi there, new to this and hope members can help. Got a new Grant ASHP, great install, worked really well, then flow temps dropped and no obvious reason for it. Grant will come out but concerned about this as our experience of manufacturers isn't good (lack of knowledge, blaming install, etc.) and wonder what to expect/what to ask. Thanks.
@sentinam, welcome to the forums and good luck with Grant. Start up a new thread when you’re ready to share your story and feedback.
Evening all, I started a thread a week or so ago but just getting round to adding an intro. Currently doing all the research on ASHP matters and this seems to be the place to do that.
We've just bought our first home in SW Scotland. It's an 1960 wimpey no fines house with external wall insulation added in the 80s or so. We're going through the process of getting an Eco 4 provider (Eco Providers Ltd) in to fit ASHP etc. Unfortunately due to the external wall insulation they won't fit any internal, and as the EWI is old I'm adding 50mm internal with breather membrane myself. Can't go back and do it once the plasterboard etc is up! The benefit is that I can get the installers to run all pipework inside walls. I think we are getting around 3.6kwh of solar, which is not as much as I wanted but the max they will do. They are also topping up the loft insulation to 270mm. So all in all I think once we are finished the house will be as insulated as we can get it. Most of my questions are in line with getting the best installation as possible. I'm well aware that the company fitting might not be the best, and my options are limited as this is a free (to me) service. I do know the ASHP will be a Grant Aerona on the south west corner, with the tank etc in the loft. I'm intending to lag all the pipes myself internally, and also externally if the stuff they put on isn't good enough.
Questions I want to ask them are:
- can we dispense with anything but the Grant/chorfu controller as that seems to be the best option
- will they make sure they enable WC for me
- Does the setup come with Eddi (if not can I supply)
- will they set pump flow and max flow temp low instead of full/high
As I say their design work isn't going to be the best I suspect, however I presume I'm best asking for the biggest rads possible? Am I also best asking for the biggest pump they will give me? There will be two zones in a 3 bed house, with the downstairs being mostly open plan and a big woodstove in the lounge. Is there a best position for the thermostats in this situation?
Can anyone suggest any other questions I should be asking at this stage?
Thanks - Josh