The heating and hot water kept breaking down as I suspect the previous occupant had installed a second-hand boiler that was extremely energy-inefficient and expensive to run. I gave Cozy Heat a call and they suggested a boiler change, new water tank in the attic and fitting a power shower to take the pressure off the heating system. They also flushed out the radiators to take out any sludge and improve their performance, lagged the pipework, and the whole system works from a small portable mobile device from which you can program the time heating or hot water comes on or goes off, and interrupt an existing program, so very flexible and user-friendly.
The result has been tremendous: water pressure on opening the taps has improved markedly and the radiators heat up the house quickly. The energy rating will have moved from an 'F' to a 'D' or possibly even a 'C' rating. I feel Cozy Heat has done a great job and that this has been money well spent. It is well worth it talking to Graeme, the engineer, as he has an impressive knowledge that demonstrates he knows what he's doing, and he explains things well to the uninitiated like me. I have no hesitation in recommending Cozy Heat, and would use them again.