The problems are huge upfront costs and lack of heat engineering knowledge of the installers resulting in rubbish installations.

These systems are subsidised via grants to the consumer such as the Boiler Upgrade Scheme paying up to £7,500 towards the cost. A typical air source heat pump, the most popular, can cost from around £7k to £13k. So you have to ask yourself why are they so expensive given they've been around for decades in Europe? It's a nice money earner for the installers and manufacturers.

As a result we're now seeing all sorts of companies suddenly popping up offering air source heat pumps. An example is a local company that fits roofing facia upgrades who now offer heat pumps. Yes they might have bought in the "expertise" but that is where the second problem is; lack of skilled heat engineers.

There are a lot of plumbers that pose as heat engineers. No doubt there are good plumbers but there are, I think, a bigger number that don't know a two port valve from a bag of candy floss.

Many of the installers have been on a one week course by a manufacturer that sells off the shelf packages based on a one size fits all. But that's where it goes pear shaped. For example, installing an ASHP in a poorly insulated Victorian house, telling the customer they're going to save thousands on their gas bill only for their electricity bill to double, triple, quadruple.

These heat pumps can work so long as they are installed by a suitably skilled qualified heating engineer, in a suitable property.

I looked into heat pumps about 15 years ago. I wasn't convinced then and I'm not convinced now because of the stupid costs and lack of skilled installers. In fact having looked into it recently again I'm less convinced now.

Buyer beware.