Leaks or damp underneath
Water on the airing cupboard floor or a damp ceiling below. A leaking joint can be fixed. A leak from the cylinder body can’t.
Hot water cylinders · Croydon
Hot water cylinder replacement in Croydon
A leaking or tired hot water cylinder doesn’t always mean a new boiler. We replace cylinders on their own or alongside a new system or regular boiler, and we’ll tell you first whether the fault really is the cylinder.
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- Used only for your quote
Fixed written price
- Gas Safe No. 567789Check us on the register
- Fixed written quoteThe price you agree is the price
- City & Guilds certifiedTrained and qualified
- Fully insuredPublic liability cover
Signs of trouble
When a cylinder is on its way out
Some of these point to a failing cylinder. Others are a part on it that can be replaced. We’ll tell you which.
Green or crusty patches
Corrosion on a copper cylinder shows as green or blue staining, often around the joints or the base. It usually gets worse.
Slow to heat
Taking far longer to heat than it used to. Scale on the heating coil is a common cause where water is hard, as it is across much of South London.
Runs out quickly
Hot at first, then lukewarm. It can be a cylinder too small for the household, or a fault in the controls.
Immersion heater problems
The immersion trips the electrics or stops heating. Often the element has failed and can be replaced on its own.
An old, thinly lagged cylinder
A cylinder in a loose fitted jacket loses heat all day. Modern cylinders come with factory-fitted foam insulation.
Fix or replace
Not every hot water problem needs a new cylinder
Lukewarm water is often a cylinder thermostat, a sticking zone valve or a programmer set wrong, not the cylinder itself. A failed immersion heater is a part that can be changed. We check these first, because replacing a sound cylinder is money you don’t need to spend.
A cylinder that leaks from its body, or is badly corroded, is a different matter. It can’t be repaired, and a leak in an airing cupboard can do a lot of damage to the ceiling below before anyone notices.
If you’re replacing your boiler anyway and the cylinder is old, doing both together saves draining the system twice. If your boiler is fairly new and the cylinder fails, the cylinder can be replaced on its own.
Your options
Like-for-like, upgrade, or lose it altogether
| Option | What it means | Good when |
|---|---|---|
| New vented cylinder | Same type, fed from the loft tank. Quickest swap | Mains flow is weak, or you want to keep things as they are |
| Unvented cylinder | Fed from the mains for mains-pressure hot water. The loft tank can go | Mains flow is strong and you want better showers in several rooms |
| No cylinder: convert to a combi | Cylinder and tanks removed, combi fitted | Smaller homes with 1 bathroom and good mains flow |
If you’re thinking of losing the cylinder altogether, see system to combi conversion.
Doing it right
What a cylinder replacement should include
Sized to the household
Based on your bathrooms and how many people use hot water, not just the size of the old one.
Matched to the boiler
A cylinder heated by the boiler has a coil inside. It needs to suit the boiler’s output so the cylinder reheats in good time.
Proper controls
A cylinder thermostat and a valve, so the boiler only heats the cylinder when it needs to.
Immersion heater
A backup for hot water if the boiler is ever off. Most cylinders come with one fitted.
Discharge pipe, if unvented
The safety discharge has to run to a safe, visible place. Its route can decide where the cylinder goes.
Old cylinder taken away
Drained, removed and disposed of properly, along with any loft tank that’s no longer needed.
Before you choose anyone
Six questions to ask any boiler installer
Including us. A good installer will be glad you asked.
- 01
“Can I see your Gas Safe ID card?”
Check the card is current and covers gas boilers. It’s on the back.
- 02
“How have you sized the boiler?”
A good answer mentions your bathrooms, hot water use and water flow, not just bedrooms.
- 03
“Is the price fixed, and what isn’t included?”
You want a written price that lists the work, not an estimate that grows on the day.
- 04
“Will you clean the system first?”
Fitting a new boiler to dirty water shortens its life and can affect the warranty.
- 05
“Who registers the warranty and notifies Building Control?”
Both should be done for you, in your name.
- 06
“What happens if something goes wrong after you leave?”
Know who to call, and how the warranty works with the installer.
FAQ
Hot water cylinder questions
Can you replace the cylinder without replacing the boiler?
Yes. If your system or regular boiler is in good order, the cylinder can be changed on its own. We’ll check the boiler and controls suit the new cylinder.
Can I add a new cylinder to my boiler quote?
Yes. In the quote form, tick “New hot water cylinder” under “Anything else while we’re there?” and add a photo of the cylinder if you can.
Can I switch from a vented to an unvented cylinder?
Often, if your mains flow and pressure are strong enough and there’s a safe route for the discharge pipe. It must be fitted by a G3-qualified installer. We’ll confirm on your quote.
My immersion heater has stopped working. Do I need a new cylinder?
Usually not. The immersion element can normally be replaced on its own. If the cylinder is also old or corroded, we’ll tell you so you can decide.
Does an unvented cylinder need servicing?
Yes. Most manufacturers ask for an annual check of the safety valves and expansion vessel to keep the warranty valid, much like a boiler service.
Guides
Read before you decide
- Choosing a boilerCombi vs system vs regular boiler: which is right for your home?Combi, system or regular boiler? How each one works, which homes each suits, and when changing type makes sense. A plain guide from Gas Safe engineers.Read the guide
- Choosing a boilerShould you repair or replace your boiler?Should you repair your boiler or replace it? An honest way to decide, looking at age, parts, repair history, efficiency and warranty, without the sales pitch.Read the guide
- Choosing a boilerQuestions to ask a boiler installerThe questions to ask any boiler installer before you book, what good answers sound like, and how to check an engineer’s Gas Safe ID card and registration.Read the guide
Everything we do
New boilers
Conversions
Repairs & servicing
Get a price for a new cylinder
A photo of your cylinder, its label and the pipes on top tells us most of what we need.