Boiler pressure and heating faults
Most combi boilers run best between 1 and 1.5 bar of pressure — too low and the heating cuts out, too high and the pressure relief valve can discharge. A plumber checking a heating fault will usually look at pressure, check for trapped air in radiators (bleeding), and check the pump and diverter valve before assuming a full boiler fault.
Workmanship guarantees on plumbing work
Most registered plumbers offer a workmanship guarantee separate from any manufacturer's warranty on parts like a boiler or a shower unit — commonly 12 months upwards. Ask what's specifically covered: a guarantee on a bathroom refit should cover the plumbing work itself, not just the visible fittings.
Protecting pipes in cold weather
Pipes in unheated spaces — lofts, garages, outbuildings — are the most common source of a winter burst pipe once temperatures drop below freezing for a sustained period. Lagging exposed pipework and keeping heating on a low constant setting during a cold snap, rather than off, are the two most effective preventive steps.
Plumbing regulations, FAQ
Do I need a certificate for a new bathroom? There's no single certificate like Part P for electrics, but any work must comply with Water Fittings Regulations, and gas-connected work needs a Gas Safe engineer. Can I do my own plumbing? Straightforward repairs, yes; anything affecting the public water supply (like a new connection) should go through a WaterSafe-approved plumber.
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.
What a good plumbing quote should include
A proper quote should state the scope of work, whether parts are included in the price or charged separately, an estimate of how long the job will take, and what happens if the job turns out to be bigger than expected once work starts (a common scenario with older pipework).
What's involved in a bathroom refit
A full bathroom refit usually means removing the old suite, checking and often replacing the pipework behind it (since it's rarely accessible again once tiled over), first-fix plumbing before tiling, then second-fix (taps, shower, toilet cistern) once the room is finished. Waterproofing (tanking) around a shower area is a step worth confirming is included, not assumed.
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.