Hot water cylinder installation in London
The cylinder is the one part of a hot water system nobody gives a moment's thought to until there suddenly is no hot water. Some are vented, fed from a tank up in the loft; others are unvented, running straight at mains pressure; and both types come with their own controls and immersion heaters attached. Ninja Plumbers replaces them, sizes new ones correctly for the household, and services the cylinders that are still doing their job.
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- DBS-checked engineers
- Emergency callout available 24/7
- Price agreed before work starts
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What's included
- Vented and unvented cylinder replacement
- Cylinder sizing based on bathrooms and usage
- Immersion heater and thermostat replacement
- Expansion vessel and pressure relief valve faults
- Annual servicing of unvented systems
- Controls, timers and cylinder stats
Worth knowing first
A bit of this might save you from needing a callout at all — we'd rather you knew it upfront.
Unvented cylinders are notifiable work
An unvented cylinder is a pressurised vessel and installing or servicing one requires a specific qualification on top of general plumbing competence. Ask whoever you are considering to show you theirs — for this work it is a fair question and a reasonable installer will not mind being asked.
Size is about bathrooms, not floor area
What decides the cylinder is how many outlets might run at once and how many people shower in the same hour. A big house with one bathroom needs less than a small house with three.
No hot water is often not the cylinder
On a vented system, the culprit is very often the immersion heater or its thermostat rather than the cylinder itself, and both of those are inexpensive to sort. Before anyone replaces a whole cylinder, those two should be ruled out first, and that is exactly the order Ninja Plumbers works through them in.
The airing cupboard is not always the best place now
Modern insulated cylinders lose very little heat, which is why an airing cupboard around one is no longer the drying space it used to be. If space is tight, a cylinder can often go somewhere more useful.
Common questions
Vented or unvented — which should I have?
Unvented gives mains pressure at every tap and needs no loft tank, which suits most modern refits. Vented is simpler, cheaper to maintain and fine where the existing tank and pressure already work.
Should I just switch to a combi instead?
Sometimes. A combi frees up the cupboard and the loft tank, but struggles where two showers run at once. For a one-bathroom flat it is often the better answer; for a family house with three bathrooms it usually is not.
Why is my hot water only lukewarm?
The usual suspects are a failed cylinder thermostat, an immersion element on its way out, or a heating coil that has scaled up over time. All three can be diagnosed without needing to replace the cylinder itself.
How often should a cylinder be serviced?
An unvented cylinder should be checked annually — the expansion vessel and safety valves are the reason. A vented cylinder needs far less, though the immersion and stat are worth checking with the boiler service.
Part of our heating & hot water work
If it turns out to be a repair job rather than a new install, this is where that's covered.
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Boiler Installation
A new boiler sized for the property, fitted properly, with the price agreed first.
More on Boiler Installation -
Boiler Service
The annual check that keeps a boiler safe, efficient and inside its warranty terms.
More on Boiler Service
Other appliance work
Need hot water cylinders in London?
Let us know what’s going on and whereabouts you are, and we’ll give you a price before any work starts.