Quote Originally Posted by Tooks View Post
In fairness, he knows this and was doing the calculations and only recommending a heat pump install if the associated improvements and installation was adhered to.

I think you two and him are in complete agreement.
I definitely wasn’t having a go at your brother. Sounds like a his customers won’t or don’t want to listen to his advice.

Like putting a small gas boiler in a very large house.

The trouble is unless the installers are very well qualified to undertake the heat loss calculations, the risk of undersizing is always present, and probably the biggest selection and installation issue. It feels like the industry is not fully established and still working the fundamentals out when it comes to older, draughty homes.

Gas boilers have been installed for decades, have good rules of thumb for radiator requirements, and unlike ASHP are very forgiving as they run a much hotter temperatures.