Guide · questions
Questions to ask a gas engineer before work starts
Most problems with gas work start with something nobody asked. These questions, in the order they come up, make sure the person in your home is registered for the job, that you understand what's being done, and that you're left with the right paperwork.
Short answer
Ask for the Gas Safe registration number and check it; check the categories on the ID card cover your appliance; agree the price and what's included; ask for any fault and any recommended replacement in writing; and make sure you leave with the right record for the work done.
01
When you book
| Ask | A good answer |
|---|---|
| Are you on the Gas Safe Register, and what’s your registration number? | A number you can check on the register’s website straight away. |
| Does your registration cover this appliance? | Boilers, cookers or gas fires, as the job needs, shown on the back of the card. |
| What will the visit cost, and what’s included? | A clear price for the visit, and how any extra work will be priced. |
| Who will actually come? | A name you can check, or the business’s registration if a colleague comes. |
02
When they arrive
| Ask | A good answer |
|---|---|
| Can I see your ID card? | A card with a photo that matches, a current expiry date and the right category. |
| What will you check or do? | A plain explanation of the work, before it starts. |
03
If they find a problem
| Ask | A good answer |
|---|---|
| What exactly is wrong, and how serious is it? | A specific fault, and whether it’s "at risk" or "immediately dangerous". |
| Is it safe to use until it’s fixed? | A clear yes or no; a labelled appliance must not be used. |
| Can you put the diagnosis in writing? | Yes, with any repair or replacement priced separately. |
04
When they finish
| Ask | A good answer |
|---|---|
| What paperwork will I get? | A service record, a gas safety record for landlords, or a building regulations certificate for a new boiler. |
| Is there anything I need to do? | Maintenance advice, and any follow-up needed. |
Why these questions
What the answers protect
Registration and categories are the legal baseline. HSE explains that a gas business must be on the Gas Safe Register to do gas work legally, and advises checking that an engineer is competent in the specific area of gas work. The ID card shows the categories on the back; the register confirms them.
The diagnosis in writing matters most when the news is bad. An appliance found "at risk" or "immediately dangerous" gets a warning label, and it's illegal to use an appliance you suspect is unsafe. A written diagnosis lets you get a second opinion before agreeing to an expensive replacement.
The paperwork is your record of what was done. For landlords, the gas safety record is a legal requirement that tenants must receive. For a new boiler, building regulations compliance matters when you sell.
Red flags
Answers that should make you pause
- "You don't need to check, I've been doing this for years."
- No ID card, or a card without the category you need.
- "It's dangerous, but I can replace it today if you sign now."
- A reluctance to put a diagnosis or price in writing.
- A request for full payment in cash before any work.
Since April 2025, false claims that an offer is only available for a very short time to push a decision have been banned outright under consumer law. A genuine engineer can explain a fault without pressure.
Landlords and tenants
Extra questions for rented homes
- Landlords: will the record cover every appliance and flue I provide? Will it include my or my agent's name and address? Can you send it electronically?
- Tenants: is this the annual gas safety check? When will I get my copy? Existing tenants should receive one within 28 days of the check.
- Both: was anything found that needs repair, and who is arranging it?
Asking well
How to ask without awkwardness
Engineers are asked for their ID card all the time; HSE actively encourages it. Asking at the door, politely, sets the tone for the rest of the visit. If you're nervous about challenging someone, check the registration online when you book, so the only question on the day is whether the card matches. Put anything that matters, like a price or a diagnosis, in an email afterwards: "Just to confirm what you told me..." gives you a record without any confrontation.
After the visit
If something isn't right afterwards
Contact the engineer or business first, in writing, explaining what's wrong and what you'd like done. If the quality of the gas work itself is the concern, the Gas Safe Register can investigate. For disputes about price, contract or service, Citizens Advice can explain your consumer rights. Keep the records from every visit; they're what any complaint will rest on. See checking an engineer and repair or replace.
And if the visit went well, keep the engineer's details with the record. An engineer who already knows your boiler and its history is often the best person to call next time.
Prices
Asking about cost
Ask about cost before the visit and again before any extra work. A clear engineer will explain the call-out or visit charge, what it includes, and how any parts or extra time will be priced, in writing if you ask. If a quote for a repair or replacement arrives on the day, it's fine to say you'd like time to think and to compare.
None of these questions should take more than a minute to answer.
Sources used on this page
- Gas Safe Register and the engineer ID card · HSE (3 November 2026)
- Domestic gas: frequently asked questions · HSE (3 November 2026)
- Gas safety check records and what to keep · HSE (3 November 2026)
- Building regulations approval: when you need it · GOV.UK (3 November 2026)
- DMCC Act 2024, Schedule 20 (banned practices) · legislation.gov.uk (2 November 2026)
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