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 our customers say.
I have used Basi for a number of years and this is the 3rd boiler they have fit for me. They are very easy to deal with, offer advice and a quick competitive quote. The jobs are planned in a timely manner and you don't have to wait long. The overall service of the office staff and fitters is friendly, professional and carried out to a high standard. The aftersales service is very good too. Would highly recommend.
New boiler fitted today! Perfect job from setting up the job, price of quote and workmanship. All very professional, friendly, super efficient and experienced. Choice of boiler was a good brand, Valliant sustan 28..really quiet whilst on and fits perfectly in my boxed unit. Good communication prior to day of fitting, fitter arrived on time, punctual and really confident in his work and know how. Reliable, friendly and really good quality workmanship. Happily completed an extra radiator job for me besides the boiler. Would recommend to future customers wanting to replace a boiler
I wanted to leave a massive thank you to Jaspal and Kultar for their incredible help recently. One of our tenant's properties had a boiler breakdown, and since it was 13 years old, it just wasn't worth repairing. I called Basi Heating, and Kultar managed to get out to the property that very same morning. It was a freezing day, and the situation was urgent because the tenants were struggling without heat or hot water—made even more critical as their grandfather lives with them. Despite being busy, Kultar managed to squeeze us in to ensure they weren't left in the cold. He handled the survey efficiently and clearly explained the situation. We received solid, honest advice along with a very competitive price. To top it off, the delivery and installation were completed within 48 hours. The experience and knowledge here speak volumes. I can't recommend them enough—keep up the fantastic work! Highly recommended. Kind Regards Roop
Got in contact with basi heating. As my old boiler wasn't safe to use. Within 5 working days they booked me in for a new boiler to be installed. The engineers arrived within the time frame given. Very professional and the installation of the new boiler is excellent. Fantastic customer service all round. Highly recommend. And will be using basi heating for the servicing of the boiler. When required.
I had Basi to install my boiler over 30 years ago, it was on its last leggs, had lots quotes and people saying it was a big job! Called Basi, came out same day, affordable price, following week it was in, great staff, explained everything, very clean, neat, quick service, highly recommended 👍
Rated 5★ from 424 reviews on Trustpilot and 4.7★ from 210 on Google. Read more customer reviews from across Yorkshire.
Questions
The questions we get asked most.
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.
Need a repair today? Call the office, not a booking form, and we can often get you a same-day appointment across BD, LS, WF, HD, HX and HG. Gas Safe engineers, parts on the van for the common faults, no separate call-out fee.