A practical checklist for comparing local boiler installers in St Albans, from Gas Safe registration and surveys to written quotes and warranty conditions.

Choosing a boiler installer is about more than comparing the number at the bottom of a quote. The survey, system design, controls and commissioning all affect how well the new boiler works in your home.

1. Verify the Gas Safe registration

Anyone carrying out gas work must be appropriately registered. Check the business or engineer on the official Gas Safe Register and confirm that the engineer's card covers the type of work required. Aphex Heating's registration number is 667664.

2. Expect a property survey

A useful survey considers hot-water demand, the number of bathrooms, radiator output, controls, existing pipework, flue position and condensate drainage. Older St Albans homes and flats can also have access or routing constraints that need checking before a boiler is chosen.

Be cautious if a recommendation is based only on the number of bedrooms. Two similar-sized homes can have different heat loss and hot-water needs.

3. Compare the written scope, not just the boiler

A clear quote should identify:

the exact boiler model and controls;
any flue, condensate or pipework changes;
how the system will be cleaned and protected;
whether a magnetic filter is included;
removal of the old appliance and waste;
commissioning and Gas Safe notification;
the expected timescale and total price.

If something is not written down, ask whether it is included before accepting the quote.

4. Understand the warranty conditions

Manufacturer warranty length can depend on the model, controls, filter, registration and annual servicing. Ask what is covered, who completes the registration and what you must do to keep the cover valid.

The longest headline warranty is not automatically the best choice. The boiler still needs to suit the property and the terms need to be practical for you.

5. Ask how the boiler was sized

An oversized boiler can cycle inefficiently, while an undersized system may struggle with heating or hot water. The installer should be able to explain the recommendation in plain language, including any radiator or control changes.

6. Check aftercare and handover

Before the installer leaves, you should understand the controls, pressure, servicing requirements and what to do if a fault appears. Ask which documents you will receive and who to contact with a question after installation.