James Thornton
MCS-certified, F-Gas Category 1 heat pump engineer with 100+ UK installations since 2019. James writes and fact-checks every guide and calculator on HeatPumpCalcs.co.uk.
About James
James Thornton is an MCS-certified heat pump engineer based in the East of England. Since 2019 he has designed, installed, and serviced over 100 air source and ground source heat pumps across Cambridgeshire, Norfolk, Suffolk and Essex — including new builds, pre-1980 solid-wall retrofits, and 14 listed buildings.
He holds MCS certification (Air Source Heat Pump scope) through NICEIC and an F-Gas Category 1 refrigerant handling qualification. He completes a room-by-room BS EN 12831 heat loss calculation on every install and tracks year-on-year SCOP performance across his customer base via MELCloud, Onecta and sensoApp data exports.
Why this site exists
James started HeatPumpCalcs because most UK heat pump information online is either oversimplified marketing or buried in technical jargon. Every calculator and guide here reflects what he sees on real jobs: the cost ranges installers actually quote, the SCOPs systems actually achieve, and the gotchas (microbore pipework, oversizing, missed weather compensation) that determine whether a heat pump saves money or disappoints.
Credentials & experience
- MCS Certification — Air Source Heat Pump (via NICEIC), held 7 years
- F-Gas Category 1 — full refrigerant handling, all system sizes
- 100+ installs across the East of England, 2019–present
- 80+ annual services per year, tracking real-world SCOP
- 14 listed-building installs including a Grade II* manor near Ely
- Works with two regional developers on Future Homes Standard compliance
Editorial standards
James writes or technically reviews every page on this site. Figures are sourced from Ofgem, MCS, DESNZ, Historic England, BRE, and his own anonymised install records. He receives no commission or incentive from any heat pump brand, installer, or energy supplier. See our Methodology and Sources for full detail.