ASHP in an old rubb...
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ASHP in an old rubblestone Welsh house

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Active Member Member
48 kWhs
Joined: 2 years ago
Posts: 3
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Hello everyone, I am a retired engineer and last employment was working for an environmental charity in Mid Wales. Following 25 years of manufacturing electro magnets, superconductors and other particle physics equipment.

We reneovated an old rubblestone built house here in Wales 12 years ago. Our upgrades were UFH, internal wall & loft insulation, DG windows, solar thermal, wood fueled range with water heating

Nant Cyff Spring 2012 004
Nant Cyff Spring 2012 003
Nant Cyff Floor insulation & Membrane 008

and a few years later a small PV array .

Budget did not permit us to add the heat pump at refurb and retricted access meant had to opt for cylinder LPG. Our own heat loss calcs showed a 12kW boiler was sufficient to replace the old 35kW oil boiler that wasn't and so it has proved. However the cost of running LPG meant we could only operate it for background heat and use our own logs for 'comfort heating'.

2019 Evergreen Energy installed a 12kW ASHP to replace the boiler and integrated it to our existing plumbing arrangements, by adding a low loss header, and Glycol thoroughout the whole heating system. No rads were added or changed and UF loops at 150 ctrs wre deemed acceptable.

3rd winter now and the HP proving to be very effective and economical, at approx 65% cost of LPG, no economic restriction on run time, house warm and comfortable all over. As we dont run exclusively on HP and use the log burner/s when the weather is a bit grim and the the UF is heating about 12 tonnes of slate flooring quarry tiles and concrete, it makes the system about as unreactive as you could get. The upside being once its warm it stays warm all day and most of the night. We set back 2 degC overnight and operate the HP from about 9 a.m. when the ambient temperature is higher.

Future ambitions include better insulated doors(oak proved unsuitable for heavy weather), shiplap weather boarding for remaning prevailing wind SW facing wall, glass canopy to cover doorway and window lintles and reduce wall weathering and water ingress.

Andris, Derek M, Andris and 1 people reacted
Illustrious Member Admin
17053 kWhs
Joined: 3 years ago
Posts: 2342

Very interesting Ant. Thanks for sharing, and welcome again to the forums. Which air source heat pump did you go for?

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