Immersion heaters and hot water cylinders
An immersion heater is an electric backup for heating water in a cylinder, useful if the boiler fails or as the main hot water source in an all-electric property. If yours is tripping the electrics or not heating water, it's sometimes the heating element itself rather than the boiler or cylinder at fault.
Three steps to hiring the right plumber
First, check they're registered with a WaterSafe scheme (or Gas Safe too, if the job needs it) and ask for the registration number. Second, get a written quote that separates labour from parts. Third, ask what happens if the job uncovers a bigger problem — a good plumber will tell you before continuing, not after.
How many quotes should you get?
Three is a reasonable number for most plumbing jobs — enough to spot an outlier without asking too many people to visit for a straightforward repair. For a planned job like a bathroom refit, make sure each quote covers the same scope, since a lower price sometimes means less is included, not better value.
Understanding the labour vs materials split
Materials — pipework, fittings, a new boiler or bathroom suite — are often a smaller share of a plumbing quote than labour, particularly for jobs involving lifting floors or chasing walls. If a quote looks unusually cheap, check whether it specifies the same brand/quality of fittings as a competing quote, not just a lower labour rate.
Combi vs system vs conventional boilers
A combi boiler heats water on demand with no separate tank, suits smaller properties with one bathroom. A system boiler uses a hot water cylinder but no cold water tank, better for higher demand. A conventional (regular) boiler uses both a cylinder and a tank, common in older properties and useful where mains pressure is poor.
Do you know where your stopcock is?
Every property has a main stopcock (usually under the kitchen sink, though sometimes in a different location in older or converted properties) that shuts off the water supply. Knowing where it is and checking it turns freely, before you need it in an emergency, is one of the simplest things a homeowner can do.
Hard water and your plumbing
In hard water areas, limescale builds up inside pipes, taps, showerheads and boiler heat exchangers over time, gradually reducing efficiency and flow. A plumber working in a hard water area may recommend a water softener or scale inhibitor as part of a boiler installation, particularly for a system that's expected to last 10+ years.
When plumbing work needs a Gas Safe engineer instead
Plumbers can install and repair most water systems, but any work on a gas appliance or gas pipework — a boiler, a gas fire, a gas hob — is illegal for anyone who isn't on the Gas Safe Register, by law. If a job involves both plumbing and a gas connection (moving a boiler, for example), check whether your plumber is also Gas Safe registered before booking.