Gas Safe checks before an ECO4 boiler install: a UK household checklist (2026)

Guide by ApplyFreeBoiler.uk (Reliant Energy Solutions Ltd), a heating and insulation installer in Bury, Greater Manchester. We are not the government, Ofgem or an energy supplier.

ECO4 heating work is carried out by registered engineers, but households still benefit from knowing what to ask before installation day. This checklist is general information and does not guarantee funding.

1. Confirm the engineer is Gas Safe registered

Ask for the engineer's Gas Safe registration number and check it on the Gas Safe Register website before work starts. The card should match the person who arrives.

2. Match the company name

The business named on your paperwork should match the employer shown for that engineer. If you are unsure, ask the installer to confirm in writing.

3. Ask what will be replaced

Confirm whether the boiler, flue, controls, pipework or radiators are included. Unexpected extras on the day are easier to avoid when the scope is written down.

4. Ask how the flue will be routed

Flues need clear external termination and correct clearances. Ask where the flue will exit and whether any boxing or decoration will be needed afterwards.

5. Keep commissioning records

After install, keep the commissioning checklist, any Benchmark certificate and Building Regulations notification with your EPC and guarantees.

6. Know who to call for faults

Ask for the aftercare contact and what to do if the boiler locks out. Report faults in writing and keep dates.

7. Compare local delivery data

See ECO measures by council on ApplyFreeBoiler.uk, built from DESNZ Household Energy Efficiency statistics.

8. Check eligibility

Use the ApplyFreeBoiler.uk eligibility check to see whether an ECO4 heating pathway may be available for your home in England, Scotland or Wales. ECO4 is due to close on 31 December 2026.