No Heating London — Emergency Repair

If your boiler fires and shows a normal display but radiators stay cold, the most common causes are: a seized or failed circulation pump (the pump that moves hot water around the system); air locks in the system (especially after draining, refilling or fitting new radiators); a faulty zone valve that isn't opening to let hot water reach the radiators; or a thermostatic radiator valve (TRV) that is stuck closed. We diagnose the specific fault with a system pressure test and flow check — most of these faults are repairable on the same visit.

Partial heating — some radiators hot, some cold — usually points to one of three causes: air in the system (the cold radiators need bleeding); a failed thermostatic radiator valve (TRV) on the cold radiators; or a pump losing head pressure that can't drive water to the furthest radiators on the circuit. In older London properties with poorly balanced systems, sludge (magnetite) build-up restricts flow through certain radiators. We carry TRV replacement kits and power-flushing equipment to address all three on the first visit.

The cost depends on the fault: circulation pump replacement typically costs £180–£350; zone valve replacement £120–£250; TRV replacement £60–£100 per valve; system balancing and bleeding £90–£180; boiler PCB (control board) fault diagnosis and repair £150–£400. Our £60 call-out fee is waived on jobs that run over 2 hours — which most heating faults do. We give a fixed price before starting work and don't add surprise supplements for evening or weekend attendance.

Yes. We operate 24/7 including weekends and bank holidays across all 33 London boroughs. Weekend labour is charged at a slightly higher rate (£110/hr vs £95/hr on weekdays) but there is no additional call-out supplement beyond the standard £60. For genuine emergencies — no heating with a vulnerable person, young child, or in sub-zero temperatures — we prioritise dispatch and aim to arrive within 60 minutes.

Boiler fault codes vary by manufacturer. Common codes that cause no heating: F22/F75 (low pressure — repressurise to 1.0–1.5 bar); F28/F29 (ignition fault — gas supply or spark electrode issue); EA (lockout — usually an overheat safety); H07 (pump fault). We carry a diagnostic tool for all major brands (Worcester Bosch, Vaillant, Baxi, Ideal, Glow-worm) and can interpret any fault code on arrival. Never attempt to continuously reset a boiler showing a fault — this can mask a gas or overheat issue.

Yes, if the pressure gauge shows below 0.8 bar, repressurising to 1.0–1.5 bar will often restore heating. Most combis have a filling loop under the boiler — turn both valves until you hear water fill, watch the gauge reach 1.2 bar, then close both valves. If pressure drops again within 24 hours, you have a leak somewhere in the system that needs finding and fixing. Repeatedly repressurising masks an underlying fault — call us if it drops more than once in a week.