Boiler help
Start with the simple checks. A good share of no-hot-water calls turn out to be a tripped switch, a timer that has lost its settings, or a prepayment meter that has run out. Five minutes of checking can save you a callout. If it's none of those, the likely faults below are engineer jobs.
Smell gas? Stop here. Open windows and doors, don’t flick switches, and call the National Gas Emergency line free on 0800 111 999 before anything else.
On a combi boiler that split usually points at the diverter valve, the part that switches the boiler between heating the radiators and heating your tap water. They wear out, and it's a common repair on boilers more than ten years old. On a system with a hot water cylinder, a failed motorised valve or cylinder thermostat has the same effect.
If the boiler is dead or locked out, work through the checks below before assuming the worst. Power, gas, pressure and a frozen condensate pipe in winter cover most of it. If the boiler is on but locked out with a fault code, note the code down before you reset: it tells me a lot before I arrive.
I’m Jamie, a Gas Safe registered engineer (No. 977838) in Burgess Hill. I handle boiler and heating repairs in Burgess Hill and across Mid Sussex, Mon to Fri with some evenings.
FAQ
On a combi it's most often the diverter valve sticking in the heating position. It's a well-known fault, parts are usually available, and it's a routine repair. On a cylinder system it's usually a motorised valve or thermostat.
Often, yes. A sticking diverter valve or a scaled-up heat exchanger both cause hot-cold-hot water on combis. Worth a proper look rather than living with it.
One reset is fine. If the fault comes back, repeated resets just stress the boiler and can hide what's actually wrong. Note the fault code and get it looked at.
Get a quote
Send me a few details, and a photo of the boiler if you can. I'll get back to you quickly with a clear, no-obligation quote and honest advice.
