@cycleneil, welcome to the forums. When you're ready, please simply start a new topic where you can ask questions about an ASHP and/or HVO bivalent system specific to your property.

@cycleneil 

Hello and welcome.  Our house was built in 1990.  We replaced doors, windows and improved the loft insulation.  I have no knowledge of biofuel or oil heating but our ASHP works really well for us.   

@cycleneil hi we are just into our 3rd week of running ASHP having previously used lpg and wood biting stoves in our basically 200 yr old stone cottage with 2 modern extensions. We have full upvc dg and have increased the insulation in the attics. The house was never warm except the large living room but as were are not softee southerners we were ok over the last 38 yrs! However lpg cost plus the threat of EPC ratings and an old boiler lead me to look at ASHP. Ours now have the whole long hose (160sqmts) Cosy and warm enough for our Hove based son to visit!  Cost is below my lpg monthly spend and I have not had the fire going for 3 weeks! Down side is the cost. We had to rip out all the old heating pipes rads etc and completely refit which was expensive and has led to some additional work total cost just under £25k. To help with ongoing costs we are looking at laying out an 8kwh solar panel system next to the house running into an 8.2 storage system. We will. Not recoup the total expense but the comfort and lower ongoing cost plus hopefully future proofing the property is worth the effort. I am a great fan of the heat pumps but sadly it is still a system that is well out of reach to many the most annoying thing being the cost bandied about by the authorities who make it seem you can get a system in for not much more than a gas boiler if you take the £5k Grant. Not so

@kev-m Hi there! You'll probably be constructed to the same building regs my house-to-be is then. At least the wall cavities are insulated and the ground floor concrete slab is too, if not to modern standards.

@sapper117 Hi There! Yes, the authorities are completely ignoring the real cost of converting properties built before the latest revision of building regs.

A brief bit of calculation of heat losses after I do the glazing and door upgrade suggests that I'd have to replace all the ground floor living area radiators with larger sized triple-panel triple-convector monsters to get the ASHP flow temperatures down to efficient levels. Might get away with just changing the upstairs rads to double-panel double-convector, but all radiators will need to be replaced.

@cycleneil hi Neil welcome to the site. Your home is same age as my Worcestershire bungalow. See Worcestershire ASHP in the ASHP folder. And the editor has done a video. Or check out Ecobubl YouTube site where they videoed Daikin Altherma 3H HT ASHP installation at my home. 
Getting several quotes is key and finding a heating engineer you trust and can answer your questions. 

@cycleneil most of the rads are not too bad at all but our living room is quite large with a large window do they have slapped in a 2.2 long rad on one wall and 1.7 on the other. The room is big enough to take them without noticing and they keep the room to 21c without any problem so the fire is now just for early and late summer evenings

@julianc Hi there! Yes, I read that thread and I will watch the video. Getting a flow temperature of more like 50degC makes the radiator size problem a whole load more manageable and cheaper. Assuming the heat pump efficiency is still good at those temperatures, of course.

I did look at Daikin's web site, but proper technical performance data was really hard to find among the whole glossy consumer sales BS.

Posted by: @cycleneil

@julianc Hi there! Yes, I read that thread and I will watch the video. Getting a flow temperature of more like 50degC makes the radiator size problem a whole load more manageable and cheaper. Assuming the heat pump efficiency is still good at those temperatures, of course.

I did look at Daikin's web site, but proper technical performance data was really hard to find among the whole glossy consumer sales BS.

@cycleneil,

50deg is about the hottest you'd want as efficiency normally starts to drop a bit before then. Our rads keep us warm at 45 deg at -3 deg outside and they aren't especially big. It is a bit of a trade off though.  

@cycleneil when my Ecobubl MCS assessment undertaken, I think 3 radiators undersized. We (my wife) decided she didn’t want mess and upheaval. So we did not change. So far so good since April 21. 
Our max temp is 54C currently. I’ve been gradually stepping it down to no detriment. Control via Nest. Will switch to weather compensation in April 22 to compare. 
My estimated SCOP is 3.28

@cycleneil, I will add that rads don't need to be a massive headache. We didn't want the hassle of redoing pipework, so we replaced several K2 with the exact same size Stelrad K3s and the difference was massive. It took less than half a day to get five rads replaced, with no pipework mods - lovely heat at 45C, and toasting when running at 50C.