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.
What WaterSafe registration means
WaterSafe is the umbrella body for the UK's Approved Contractor Person schemes (including APHC, CIPHE, WIAPS and SNIPEF). A WaterSafe-approved plumber has been assessed on their knowledge of the Water Fittings Regulations, which exist to stop poor installation work or substandard products contaminating the drinking water supply — not just general plumbing competence.
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.
Plumbing responsibilities for landlords
Landlords are responsible for keeping water and heating systems in safe working order, and if there's a gas boiler, a valid annual Gas Safety Certificate is a legal requirement, not optional. A burst pipe or heating failure in a rented property is generally treated as an emergency repair the landlord must address promptly.
How long does plumbing work take?
A tap or valve replacement is usually under an hour. A full bathroom refit commonly takes 5 to 10 working days depending on scope, plus time for tiling and decorating that isn't part of the plumbing work itself. A boiler swap is typically a one-day job if it's a straightforward like-for-like replacement.
What affects the cost
Cost depends on the scope of the job, how accessible the pipework is (under a floor vs behind a wall), whether parts need to be sourced specially, and whether the job is planned or an emergency call-out. A simple tap or valve replacement is usually quick and low-cost; anything requiring pipework to be rerouted, or walls/floors to be opened up, costs more partly because of the making-good work afterwards.
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.
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.