Plumbing repairs in London

On a combi boiler this usually points to a faulty diverter valve, which switches the boiler between heating and hot water. On a system with a cylinder, check the timer and cylinder thermostat first. If both are set correctly, a motorised valve or thermostat may have failed and needs replacing.

A Saniflo that keeps running usually has a stuck or worn pressure switch, a leaking non-return valve letting water flow back, or a dripping tap or cistern feeding it. Turn off the water to the toilet to see if it stops. If it keeps cycling, the switch or valve needs replacing.

Pour a bucket of hot (not boiling) water into the pan from waist height, wait a few minutes and repeat. Washing-up liquid can help with grease. Don't use caustic chemicals, which can damage pipes and harm whoever clears the blockage next. If the water keeps rising, stop flushing and call us.

Water trickling into the pan usually means the flush valve seal is worn, or the fill valve isn't shutting off and water is escaping down the overflow. Both are inexpensive parts to replace. Lifting the cistern lid and watching where the water goes usually shows which one has failed.