Air source heat pumps

[Murox]

We have wet underfloor heating/ hot water run by a solid fuel Rayburn. The cottage was built in the 1800s with thick stone walls. We have put in double glazing but apart from that I’m lost where to start.

Worst thing I ever did was to replace a gravity based wet system heated by Rayburn with a pumped system heated by oil. Thankfully we moved house and I was able to install a new Rayburn to a wet system albeit pumped.

 

[Sutty]

We have wet underfloor heating/ hot water run by a solid fuel Rayburn. The cottage was built in the 1800s with thick stone walls. We have put in double glazing but apart from that I’m lost where to start.

We're in a similar position, part of the house dates back to 16th century, "newer" bit is elizabethan, apart from a new extension by us 20 years ago.
Thick stone walls, listed so external insulation definitely out (& we wouldn't). We only installed double glazing a year ago, after having to apply for permission & having to use an expensive, though sympathetic, option.
Internal insulation remains an option as and when we redecorate each room.
A hybrid system might be an option (googled it) but might not be very beneficial!