A boiler is a major purchase that affects your comfort and bills for the next 12–15 years. Here are the questions that actually matter.
1. What size boiler do I need?
Output (kW) should be sized to your home. An oversized boiler short-cycles and wastes gas. Always ask your installer to justify their recommended output.
2. What type of boiler is right for my home?
Combi, system, or heat-only? Each has different requirements and benefits. Read our comparison guide.
3. What warranty comes with this?
Manufacturer warranties range from 2 to 12 years. Always ask what's included and whether annual service is required to maintain it.
4. Is the installer Gas Safe registered?
Ask to see their Gas Safe ID card. Non-registration is illegal.
5. What brand are you recommending and why?
A good installer explains their recommendation. If they only offer one brand, ask why.
6. What else is included — flue, filter, controls?
Make sure the quote includes a magnetic filter, inhibitor, and appropriate controls — not just the boiler.
7. Do I need a power flush?
If your system is old, a power flush may be required. Ask the engineer to inspect and advise honestly.
8. What are the payment options?
Ask about 0% finance — it's often the smartest financial choice. See our finance options.
9. What Building Regulations certificates will I receive?
You should receive a Gas Safe certificate and Building Regulations compliance certificate.
10. What is your emergency cover?
Ask how quickly they can attend if something goes wrong post-installation.