How does a heat pump work?

The Heat pump principle.

The refrigerant in the heat pump evaporates (Boyles Law) at low temeratures, the source energy whether air or water routes through the evaporator (heat exchanger) where the refrigerant circulates. The regrigerant extracts the energy and the refrigerant changes from a liquid into a gas, a scroll compressor draws the regrigerant in and compresses it.


The increase in pressure raises the temperature. The compressor is is of a suction gas cooled designed so the energy/heat of the electric motor is not lost but reaches the downstream condenser together with the compressed regrigerant.


The refrigerant releases it’s absorbed energy to the circulating system via the condenser to the circulating system to the hot water and heating circuit, The expansion valve deduces the pressure of the refrigerant for the process to start all over again. To learn more and see a diagram please click on this link andit will take you to the web page.


Unemployed people, desperate for new jobs in a tough market are paying thousands for courses in plumbing – only to find they can’t find work and nursing a loan they find difficult to pay.

It is sad but true, I have just read this interesting article in the Guardian by Jamie Elliott about people desperate for work who are being cajoled into taking up ‘fast track’ plumbing courses. The link to the article is

The bottom line is there is no work for the plumbers we have, so the only people who are making money are the organisations running the training courses.

Department of Energy and Climate Change Blog

Department of Energy and Climate Change Blog.

Department of Energy and Climate Change Blog

Department of Energy and Climate Change Blog.

Eco-house for Subheat

Subheat are looking for a small building plot to build a low carbon timber framed sustainable house which will be built to a ‘tight’ budget. It is our intention to demonstrate a cost conscious ‘low carbon’ dwelling can be affordable to first time buyers using the best energy solutions including a heat pump and heat recovery ventilation. All we need is that small plot of land in North Yorkshire.

New website


I am just starting to get to grips with blogging, hopefully I can add a lot of useful content regarding energy efficiency for low carbon buildings and link it through subheat

Subheat asks – Price or Performance?

I can recall many instances over the past 10 years where I have been called out and inspected a faulty under floor heating installation, I discovered that the under floor heating systems generally have been designed­­ on the border of normal operation to, I assume, reduce the overall amount of the materials required, and thereby make the cost for the project more attractive against rival companies, but at what cost to the end user? Continue reading