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New here, I've lurked for a while and read plenty but now I feel it's time to ask my questions. I am one of life's over thinkers so I apologise in advance. 🤣🤣
Hi,
Have been reading for a bit - and now trying to get to grips with the new ASHP..... which is definitely easier said than done.
Wow I wish I had found this forum before now! I’ve been researching for ages.
Grant Aerona 13KW ASHP being installed before Christmas. Coming away from oil.
5.46KW solar array being installed February on our new garage roof (under construction).
10KW solar battery with 5KW inverter being installed alongside.
@marvinator80, welcome to the forums and we look forward to hearing all about your system when it's installed. Please feel free to start a new thread dedicated to your system when you're ready.
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Hi all, we moved into our relatively modern (2015) house in the Heart of Scotland in 2019 and I have been toying with changing from gas combi to heat pump for a couple of years now. At the outset I was put off by the "need to change plumbing and radiators" brigade because that isn't going to happen, it would cause too much damage and wipe out any realistic payback. Then I got excited about hybrid which in the short term seems like a good idea but still leaves us with gas and a big part of our reasoning is to be rid if it now before we are forced to in 10 years time when we are 80. So now we are back to full HP the can of worms of which is driving me nuts.
So that's why I am here.
Welcome @alistairgbarron - and you are certainly not alone in the quest you mention!
There are a number of possible 'solutions' being discussed here on the RHH Forum... any of which might appeal, depending on your background knowledge and how much of the 'work' you want to do yourself.
We have a very active 'live' discussion about a 12kW Samsung heat pump installation which isn't behaving as it should, but yet achieving pleasantly high efficiency (COP around 4.0). Of particular note are the comments about the Flow Water Temperature being around 50degC max.
That's a very important concept to grasp. If you're looking towards a hybrid system, the part which is gas-fueled needs to mesh with a heat-pump which is optimal at a lower temperature range.
Whether your existing radiators are adequately sized to deliver the heat-input required for your house is probably the first question to get answered. Let me be the first here to recommend that you pay £400-500 for a properly-qualified surveyor (PAS 2035) to undertake the 'energy and insulation assessment' which must form the basis of any solution. If you commission the survey, then you own it outright, and it can be used to inform and compare quotations from any prospective installer. How does that sound?
Save energy... recycle electrons!
@alistairgbarron welcome. Let me say I’m not a fan of hybrid systems. Too complex. But I understand why they might be necessary. Try turning the radiator flow temperature down to 45-50C today and see if your home maintains a reasonable temperature at different external temperatures.
A quote for a hybrid oil system got me into ASHPs - it was an 8kW together with my oil boiler. My logic was: couldn’t I get a bigger ASHP and do away with the oil boiler. That what we did 20 months ago. Documented in this forum under Worcestershire ASHP.
Having said all that every home is different so I like @transparent suggestion of a full survey but try my freebie first what is your annual energy consumption?
Daikin Altherma 3H HT 12kWh ASHP with Mixergy h/w cylinder; 4kW solar PV with Solic 200 electric diverter; Honda e and Volvo EX30 Ultra Twin Performance electric vehicles with Myenergi Zappi mk1 & Ohme chargers
@transparent - Thx. I have just made a detailed post to the ASHP section here. I do have a recent EPC but of course that tells you nothing.
I did a survey of the rads and they are all well oversized both by room and as a whole. I have all of the building regs drawings complete with design U values and have done a whole envelope heat loss calculation based on that. My preferred installer is coming to survey (I pay for and own) next week so I hope we can reach a working solution.
@julianc Hi, our boiler temp has always been set at around 50C and it heats the house just fine. It only goes above that if there has been HW demand.
Posted by: @alistairgbarronHi all, we moved into our relatively modern (2015) house in the Heart of Scotland in 2019 and I have been toying with changing from gas combi to heat pump for a couple of years now. At the outset I was put off by the "need to change plumbing and radiators" brigade because that isn't going to happen, it would cause too much damage and wipe out any realistic payback. Then I got excited about hybrid which in the short term seems like a good idea but still leaves us with gas and a big part of our reasoning is to be rid if it now before we are forced to in 10 years time when we are 80. So now we are back to full HP the can of worms of which is driving me nuts.
So that's why I am here.
hello. Changing from oil to ASHP we are only having to change some radiators from K1 to K2. Slightly thicker radiators. Same existing fittings.
Hi. Just built a new house. 2 x ashp 24 x solar panels, batteries and lots of questions.
@abefroman, welcome to the forums. Please feel free to start a new thread for your property and set up, where you can ask specific questions.
New to heat pumps? Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
🎧 Prefer to listen? Heat Pumps Explained
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