Hot water cylinders, installed and repaired properly
Plumbing
Hot water cylinders, installed and repaired properly
Vented and unvented hot water cylinder installation, replacement and repair across Yorkshire. G3 certified for unvented systems, fixed-price quotes, written commissioning sheet, no surprises.
Vented vs unvented, in plain English
A vented cylinder feeds from a header tank in the loft, runs at low pressure, and is the system most older Yorkshire homes have. An unvented cylinder takes mains-pressure cold water directly, heats it, and delivers it at full pressure to every tap and shower in the house. Showers feel completely different on an unvented system: no pumps needed, no flow drop when someone flushes the loo. Unvented does need a safety expansion vessel and a discharge pipe to the outside, and the installer has to be G3 certified by law. We are.
Why G3 certification matters
Unvented cylinders hold ~150 litres of water at mains pressure under heat. They need to be installed by an engineer who’s passed the G3 qualification, with the right safety devices, the discharge pipe sized and routed correctly, and a commissioning sheet signed and left with you for Building Control and your home insurance. A non-G3 fitter installing an unvented cylinder is not just substandard, it’s a legal issue if anything goes wrong. Every BASI engineer who quotes a cylinder job is G3 qualified.
Repair, replacement or upgrade
Not every cylinder failure means a new tank. Failed immersion heaters, leaky service valves, stuck thermostats and air locks are common and repairable. We diagnose first and quote both options if both make sense. If the cylinder itself has sprung a leak the insulation will be soaked through and replacement is the only real answer; we’ll show you why and quote a fixed price for the swap. Upgrading from vented to unvented is a popular choice when families grow and showers need to feel like showers, and is often booked alongside a new boiler installation so the whole hot-water system is sorted in one visit.
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What Yorkshire homeowners say.
Replaced our 25-year-old boiler in a single day. Tidy, polite, on the dot. Couldn't fault them.
Quoted fixed-price, no surprises. The engineer explained every step. Brilliant from start to finish.
Came out same day when our heating packed in mid-winter. Absolute lifesavers.
Used BASI for years for our annual service. Always punctual, always thorough.
Family-run, Yorkshire through and through. You can tell they actually care.
New Vaillant, 10-year warranty, finance sorted in a phone call. Smoothest install we have had.
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Questions
Things people ask. The honest answers.
Vented or unvented, which one do I need?
Vented cylinders (with a tank in the loft) are simpler and cheaper but mains pressure is reduced. Unvented cylinders run at mains pressure straight to the taps, so showers are much stronger. Most replacement jobs we quote are unvented unless the loft layout or property type really suits a vented system. We talk you through both at survey.
Why does an unvented cylinder need G3 certification?
Unvented systems are pressurised, so they need a registered installer (G3 qualified) by law. We're G3 certified, so the install is signed off correctly with a commissioning sheet that satisfies Building Control and your home insurance. Not all heating engineers can fit an unvented cylinder; we do.
How much does a new hot water cylinder cost?
A like-for-like vented cylinder swap typically runs £950 to £1,400 fitted. An unvented cylinder install (including the safety expansion vessel and discharge pipework) typically runs £1,800 to £2,500 fitted depending on the cylinder size and the access. We give a fixed written price after a 30-minute survey.
Can you repair a cylinder instead of replacing it?
Sometimes, yes. Failed immersion heaters, leaky valves, stuck thermostats and air-locked pipework are all repairable. If the cylinder itself has failed (sprung a leak from the tank), replacement is almost always the right call because the insulation is also wet by then. We'll quote both options and explain the trade-off.
How long does the install take?
A like-for-like cylinder swap is usually a single day with heating and hot water back on by evening. A change from vented to unvented (with new pipework, safety vessel and discharge to outside) typically takes two days. We confirm the timescale in the fixed-price quote.
Boiler down right now?
No heat or hot water? Call us, we will pick up.
Same-day cover where we can across BD, LS, WF, HD, HX and HG. Gas Safe engineers, parts on the van for the common faults, no separate call-out fee.