- A room-by-room heat loss calculation — not a rule of thumb. The size should come from it.
- The design flow temperature, and what it means for your radiators.
- The efficiency figure (SCOP) behind the running-cost promise, at that flow temperature.
- Weather compensation — set up and shown to you, or left on a fixed temperature?
- Cylinder, pipework and flow — the boring bits that cause most real problems.
Home › Ask the Engineer
Send me your quote. I'll check it — as a person — for free.
I'm Darren Emery. For over 40 years I worked in industries where nobody takes a design figure on trust. Now I use that to check Homeowners' quotes for Solar, Batteries, Heat Pumps and EV chargers.
The Engineer's Desk
How I check a quote
Trust the meter, not the brochure. Every system is designed to a figure. I check whether the quote's figure is believable for your home — and whether the installer has done the work that proves it.
- A generation estimate made properly for your roof, with shading accounted for.
- The payback sum — what electricity price and export rate have they assumed?
- Battery size against your real use, and whether it's set to your Tariff's times.
- EV chargers: main fuse checked, load management, and the right grant (if any).
What I won't do: visit or survey your home, or change a verdict for money. Nobody can pay for a verdict — a Red stays Red.