Choosing a heat pump installer: what to ask

Confirm they are MCS certified for the specific technology you want (air source or ground source are certified separately) — check the number against the public MCS register rather than taking a badge at face value.

Ask for a written quote that sets out the heat loss survey, the proposed unit size, and what's included (commissioning, controls, any groundworks). A proper heat loss calculation, not a guess, should drive the system size.

Ask how they handle the Boiler Upgrade Scheme grant paperwork, and get the grant deducted amount confirmed in writing before work starts.

Get more than one quote where possible. This site does not recommend one installer over another — listings are ordered by distance or county, not by payment, and any "Featured" listing is clearly labelled as such.