Common heating myths, busted
"Leaving heating on low all day is cheaper than on/off" — not reliably true; it depends on the property's insulation and the specific system. "A hissing boiler just needs bleeding" — hissing more often points to a pump or valve issue than trapped air. "Bigger boiler means faster hot water for everyone" — it's more about cylinder size and flow rate than boiler output alone.
Why Gas Safe registration is a legal requirement
Anyone installing, servicing or repairing a gas appliance or gas pipework in the UK must by law be on the Gas Safe Register, which replaced CORGI in 2009. This covers boilers, gas fires and gas cookers. Using an unregistered engineer for gas work isn't just risky, it's illegal, and any resulting certificate isn't valid.
Water-based underfloor heating and your boiler
A water-based underfloor heating system runs off the boiler via a manifold, usually at a lower flow temperature than radiators, and needs the floor buildup to accommodate the pipework. It's often more efficient paired with a heat pump than a gas boiler, because of that lower operating temperature.
What affects the cost
Cost depends on the type of system (combi vs system vs conventional), whether it's a straightforward swap or a full system change, boiler brand and output size, and property access. Moving a boiler's location, rather than replacing it in place, adds cost because of the extra pipework, flue routing and making good involved.
What a boiler fault code usually means
Modern boilers display a fault code rather than just stopping — the exact code varies by manufacturer, but common causes include low pressure, a faulty sensor, an ignition fault or condensate pipe freezing in cold weather. Note the code and the boiler make/model before calling; it speeds up diagnosis considerably.
Understanding the labour vs materials split
The boiler itself is often the largest single cost, but labour, flue work, and any additional pipework or radiator changes add up. If a quote looks cheap, check it specifies the same boiler tier (entry-level vs mid-range) as a competing quote, not just a lower labour charge.
Electric boilers, pros and cons
Electric boilers avoid combustion entirely (no flue, no CO risk, no Gas Safe requirement) but electricity typically costs more per unit than gas, so running costs can be higher for the same heat output. They suit smaller properties or as a backup rather than being the default choice for most UK homes.
Boiler cover and service plans
Separate from a manufacturer's warranty, some homeowners take out an annual boiler cover plan (often through an energy supplier) that includes servicing and breakdown cover. Worth checking what's already included in a recent warranty before paying for overlapping cover.