Boiler guides
Straight answers on choosing, installing, running and fixing a gas boiler. No jargon, no sales pitch.
Choosing a boiler
- Combi vs system vs regular boiler: which is right for your home?Combi, system or regular boiler? How each one works, which homes each suits, and when changing type makes sense. A plain guide from Gas Safe engineers.Read
- What size boiler do I need?What size boiler do you need? How kW, mains flow rate, bathrooms and heat loss decide it, why bigger isn’t better, and the rough sizes for flats and houses.Read
- Questions to ask a boiler installerThe questions to ask any boiler installer before you book, what good answers sound like, and how to check an engineer’s Gas Safe ID card and registration.Read
- Can I still get a gas boiler?Can you still get a new gas boiler? Yes, for existing homes. What the rules are for new builds, what a replacement must meet, and how heat pumps compare.Read
- What is a back boiler?What a back boiler is, how to tell if you have one, why they were fitted in 1930s and post-war homes, and what replacing one with a modern boiler involves.Read
- Signs you need a new boilerThe signs a boiler is reaching the end of its life: age, repeat breakdowns, obsolete parts, leaks, noise, soot or a yellow flame, and what to do.Read
- Should you repair or replace your boiler?Should you repair your boiler or replace it? An honest way to decide, looking at age, parts, repair history, efficiency and warranty, without the sales pitch.Read
- Combi boilers: water pressure and flow rate explainedWhy your mains water flow rate matters for a combi boiler, the difference between pressure and flow, a simple home test, and what to do if it’s low.Read
Installation
- How long does a boiler installation take?How long does a new boiler installation take? Like-for-like swaps are usually done in a day, moves and conversions take 1 to 3 days. What makes a job longer.Read
- What happens on boiler installation day?What happens when a new boiler is fitted, stage by stage, from dust sheets to handover. Plus how to prepare: access, parking, pets and finding your stopcock.Read
Rules and paperwork
- Boiler Plus regulations explainedWhat Boiler Plus means for a new gas boiler in England: the controls every boiler needs, the extra measure a combi needs, and what to check when you buy.Read
- Building Regulations certificate for a new boilerWhy a new boiler needs a Building Regulations Compliance Certificate, how notification through the Gas Safe Register works, and what to do if you never got one.Read
- Boiler warranties explainedHow boiler warranties work: registration, annual servicing, the Benchmark checklist, what can void a warranty, and the difference from an installer’s guarantee.Read
Fixing problems
- How to repressurise a boilerHow to top up your boiler pressure using the filling loop, what the gauge should read, and what it means if the pressure keeps dropping. Safe steps only.Read
- Frozen condensate pipe: how to thaw itBoiler stopped in a frost? It’s often a frozen condensate pipe. How to find it, thaw it safely with warm water, reset the boiler and stop it happening again.Read
- How to bleed a radiatorRadiator cold at the top? How to bleed it safely with a radiator key, what to do about the boiler pressure afterwards, and what a cold bottom means instead.Read
Get a fixed price for your boiler
Answer a few quick questions, add a photo if you can, and a Gas Safe engineer will come back to you with a price.