KB Heating & Plumbing repairs hot water cylinders, immersion heaters and unvented cylinders across Cardiff, Penarth, Caerphilly and the Vale of Glamorgan. KB Heating & Plumbing is a Gas Safe registered business (registration number 516445) based at 13 Wyfan Place, Cardiff CF14 3DT, with 20 years of trade experience and a 24/7 service. Call 07812 510121.
Which hot water systems KB Heating & Plumbing repairs
Most Cardiff homes that are not on a combi boiler store their hot water in a cylinder. KB Heating & Plumbing works on the three types found in local homes:
- Vented copper cylinders, usually in an airing cupboard and fed by a cold water tank in the loft. These are common in the older terraces of Roath, Cathays, Canton and Splott.
- Unvented cylinders, which run at mains pressure and need an engineer qualified in unvented hot water systems to work on them safely.
- Electric immersion heaters, fitted inside a cylinder either as the only heat source or as a backup to the boiler.
If your home has a combi boiler and no cylinder, the hot water fault is in the boiler itself. See boiler repair in Cardiff or combi boiler repair instead.
Signs your hot water cylinder needs repair
- No hot water, even though the boiler or immersion heater is on.
- Water that is warm but never properly hot.
- The immersion heater tripping the electrics.
- Hot water that runs out much faster than it used to.
- Water around the base of the cylinder or a damp airing cupboard.
- Discharge from the tundish or pressure relief pipe on an unvented cylinder.
- Banging, hissing or knocking from the cylinder or pipework.
Water coming from the discharge pipe of an unvented cylinder means a safety valve has opened. Switch off the boiler and the immersion heater and call KB Heating & Plumbing on 07812 510121, day or night.
How KB Heating & Plumbing repairs a hot water cylinder
The engineer first identifies the cylinder type and how it is heated: by the boiler through a coil, by an immersion heater, or both. Each part is then tested in turn:
- Immersion heater element and thermostat.
- Cylinder thermostat and the motorised valve that sends boiler heat to the cylinder.
- Programmer or timer settings.
- On unvented cylinders, the expansion vessel charge, the pressure reducing valve, and the temperature and pressure relief valves.
- The cylinder body and joints, for leaks or corrosion.
You get the diagnosis and a quote before any repair starts. Element, thermostat and valve replacements are usually finished on the same visit. If the cylinder itself is leaking or corroded, repair is rarely worth it, and KB Heating & Plumbing will say so and quote for hot water cylinder replacement or an unvented cylinder installation.
Hot water cylinder repair cost in Cardiff
The cost depends on the cylinder type and which part has failed. Replacing an immersion element or thermostat is at the lower end. Unvented cylinder valve work and motorised valve faults cost more. KB Heating & Plumbing always quotes before starting work.
Hot water cylinder repair FAQs
Why is my immersion heater on but the water is cold?
The usual causes are a burnt-out element or a failed thermostat. Both can be tested on site and, in most cases, replaced the same day.
Who can repair an unvented cylinder?
Unvented cylinders run at mains pressure and are covered by Building Regulations (Part G). Work on them should only be done by an engineer qualified in unvented hot water systems.
Do you cover areas outside Cardiff?
Yes. KB Heating & Plumbing covers all of Cardiff, plus Penarth, Caerphilly and the Vale of Glamorgan.