Site survey and sizing
We inspect your property, check hot water demand and pipework, then recommend a correctly sized cylinder or combi solution and provide a clear written quote.
TJ&H · St Asaph & North Wales
Hot Water Systems in St Asaph
Reliable domestic hot water installation, servicing and repairs in St Asaph and North Wales. Cylinders, immersion heaters and combi hot water functions sized for your home and backed by certified engineers.
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Hot Water Systems You Can Trust
Customers praise our fast response and clear communication after 18 years serving St Asaph and North Wales. TJ&H PLUMBING & HEATING LIMITED install, maintain and repair domestic hot water systems, including vented and unvented cylinders, thermal stores, immersion heaters and combi boiler hot water functions. We size systems to household demand, optimise for efficiency and safety and back work with a 12 month workmanship guarantee. Gas Safe and OFTEC accredited, we provide same-day emergency call-outs and WhatsApp updates for every job.
How It Works
Installation or repair
Work is carried out by Gas Safe and OFTEC accredited engineers using trusted components, with attention to ventilation, insulation and safe flueing where applicable.
Commissioning and handover
We flush and test the system, show you how controls work, register warranties and leave written commissioning notes plus our 12 month workmanship guarantee.
Why Choose us for Hot Water Systems?
18 years local experience
Nearly two decades working in homes across St Asaph and North Wales means practical knowledge handling tight lofts, older pipework and modern builds.
Certified for safety
Gas Safe and OFTEC accreditation ensures gas and oil hot water work meets regulations, with safe installation, testing and sign-off on completion.
Responsive, guaranteed service
Same-day emergency call-outs minimise cold showers, while every job has a 12 month workmanship guarantee and clear post-installation care.
What this service covers
What we cover: installations, cylinder replacements, immersion heater repairs, combi boiler hot water faults and upgrades to unvented systems. We size hot water cylinders and immersion elements to match family demand, taking into account shower use, baths and kitchen needs so you get reliable flow and recovery.
Technical approach: we assess vented versus unvented options, insulation, cold feed arrangements and expansion control. For cylinders we check anode condition, coil health and immersion elements. For combi hot water functions we test diverter valves, flow rates and system pressures. All work is recorded and left with commissioning notes so your plumber next time has a clear baseline.
Frequently Asked Questions
How do I know what cylinder size I need?
We base size on household profile: number of bathrooms, typical simultaneous use and peak demand such as a power shower. On our survey we calculate litres required and recommend a cylinder or combi that delivers the flow and recovery you need.
Can you convert a vented system to unvented?
Yes, conversions are common but require good mains pressure, an expansion vessel and safety fittings. We survey pipework and cold supply to confirm suitability and explain required changes before providing a written quote.
Do you service immersion heaters and cylinders?
We service immersion heaters, check elements and thermostats, inspect cylinders for corrosion and anode condition, and advise on lagging. Regular servicing helps maintain efficiency and extends appliance life.
My combi boiler supplies heating but no hot water, can you fix it?
We diagnose combi hot water faults by testing the diverter valve, flow sensor and pump. Many issues are repairable on the day, but we will explain whether a part replacement or further work is required and provide a clear costed option.
Do you offer emergency hot water repairs?
Yes, TJ&H offers same-day emergency call-outs for urgent loss of hot water. We aim to restore supply quickly and provide interim measures where needed, followed by a permanent repair or replacement as agreed.
Coverage & related services
Based in St Asaph, we cover surrounding North Wales towns. Check the areas we serve or contact us with your postcode.