Thermal Store Repair London

Thermal store repair and common faults

A thermal store keeps a volume of hot primary water and heats your tap water instantly through a coil or plate inside the unit, which is why it delivers mains pressure without the G3 discharge arrangements of an unvented cylinder. Faults concentrate in a handful of places: the immersion heaters, the store and control thermostats, the blending valve that limits outlet temperature, the pump on pumped models and the internal heat exchanger itself. We test electrically and hydraulically on site and repair in place wherever the store body is sound.

• Immersion element and thermostat testing and replacement
• Blending and thermostatic mixing valve faults
• Control PCB, wiring centre and timer faults
• Pump failure on pumped thermal stores
• Pressure and expansion faults on the primary side

No hot water from a thermal store

No hot water usually means the store is not being heated rather than the tap-water side having failed — a tripped immersion, a failed thermostat or a boiler not firing to the store. Hot water that starts hot and goes cold within a minute points at a scaled or blocked internal heat exchanger, which cannot transfer heat quickly enough to keep up with the draw-off. Lukewarm water across all taps is commonly a blending valve that has drifted or seized. Each of these has a different fix, and guessing is expensive.

• No hot water but heating still working
• Hot water runs hot then cold
• Lukewarm water at every outlet
• Store not reaching temperature or cycling

Heat exchanger repair and descaling

London water is hard, and the internal heat exchanger in a thermal store is the component that suffers. Scale narrows the plate or coil passages and the first sign is a drop in hot water flow rate or temperature at the highest-demand outlet. Where the exchanger is accessible we chemically descale and flush it and re-test the flow rate against the original figures. Where the coil has failed or the unit has internal corrosion, we say so and price a replacement rather than charging for repeated cleans.

Gledhill thermal store and Boilermate repair

Gledhill units — Boilermate A-Class, BMA, Pulsacoil III, Pulsacoil Stainless and Torrent — are the most common thermal stores in London flats and ex-local-authority blocks. We repair them regularly and know the usual failure points: PCB faults on Pulsacoil, immersion and thermostat failures on Boilermate, and pump and blending valve problems across the range. See our Gledhill pages for brand-specific service and spares support, or call us for a same-day diagnosis.

• Gledhill thermal store repair and service
• Gledhill Boilermate repair, including A-Class and BMA
• Pulsacoil PCB, pump and element faults
• Torrent and stainless variants supported

Servicing and replacement

An annual service keeps a thermal store efficient and safe: elements and thermostats tested, blending valve temperature verified, expansion and pressure checked, controls proved and the heat exchanger performance measured. Replacement becomes the right answer when the store is leaking, the exchanger has failed, or the model is obsolete and spares are no longer produced. Where a store is being replaced we will discuss whether a modern unvented cylinder suits the property better, and quote both options.