Hot water cylinder
- Recurring
The short answer
Unvented and immersion repair or replace
- Price from
- £80.00
- Time on site
- 1 to 4 hours
What you get
You get a professional assessment of your hot water cylinder needs, including repair, replacement options, and a clear quote for the work.
- Typical service: £80 to £150 a year
- Includes testing safety valves and recharging the expansion vessel
- Replacement valves are extra
When do you need a Hot water cylinder?
You should book a safety check every twelve months for your pressurised hot water system.
- Landlords must keep all water heating equipment in safe working order.
- Most manufacturers require annual checks to keep your warranty valid.
- You need this if you have no cold tank in the loft.
- Regular checks prevent safety valves from leaking or failing.
- The law requires these high pressure systems to be professionally maintained.
- As a guide, expect to pay around £80 to £150.
What happens on the day
A qualified expert will visit to test all the safety parts on your tank.
- They check the tank and pipes for leaks or rust.
- The engineer tests the pressure and temperature relief valves.
- They recharge the expansion vessel with air if needed.
- The specialist checks the tundish pipe is clear and safe.
- They test the thermostat to prevent bacteria and scalding.
- You will receive a service record once they finish.
How to prepare
- Clear all items stored around the cylinder
- Ensure the engineer can reach the wall valves
- Identify where your main water stopcock is
- Check if your cylinder uses gas or electricity
- Have your previous service records ready to show
- Keep children and pets away from the work area
- Ensure there is good lighting in the cupboard
How to improve your result
- Insulate all visible hot water pipes
- Check the thermostat is set to sixty degrees
- Fix any dripping taps to save hot water
- Install a timer to heat water only when needed
- Look at the tundish monthly for any drips
Why it is useful day to day
A well maintained cylinder gives you better water pressure and lower energy bills.
- Enjoy strong water pressure in every shower and tap.
- Save money by ensuring your heater works efficiently.
- Get peace of mind that your high pressure tank is safe.
- Stop annoying drips from external overflow pipes.
- Avoid expensive emergency repairs by catching small faults early.
- Keep your hot water clean and free from harmful bacteria.
Why we ask these questions
Your engineer will explain how your system stays safe and efficient during the visit.
- Why the safety valves are vital for high pressure units.
- How the expansion vessel protects your pipes from bursting.
- What the plastic tundish funnel shows you about your system.
- Why the water temperature must stay at a specific level.
- How a service record protects your home insurance and warranty.
- Which parts might need replacing in the future.
Frequently asked questions
Often needed alongside
- Fixed price
- Recurring
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Service plus safety check
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Oil & LPG system check
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Gas fire & stove service
Service or repair fires and stoves
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Boiler breakdown
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Radiators & valves
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System power flush
Clean sludge from heating
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Sockets, switches & lights
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