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Planned work · London · from £1,450 fitted

Unvented Hot Water Cylinder Installation in London

Mains-pressure hot water at every tap, no loft tank, showers that feel like showers.

Get a fixed quote Or call 020 3674 8514
Unvented cylinder installation in London
No call-out feeNo night or weekend surchargeFixed price before we start12-month workmanship guarantee

Unvented cylinders are the upgrade older London homes feel most, installed by G3-qualified engineers, because the law and physics both insist.

What you get

What the price includes

  • 01
    G3 qualified installation

    Unvented work legally requires the G3 ticket, ours carry it, and the Building Regs notification is included.

  • 02
    Sized for the household

    Bathrooms, occupants and mains flow measured; an undersized cylinder runs cold, an oversized one runs bills.

  • 03
    Safety stack done right

    Tundish, discharge pipework and expansion controls installed to spec, the parts that make “unvented” safe.

  • 04
    Annual service available

    The expansion vessel and safety valves want a yearly check, pairs with the boiler service visit.

Straight answers

Unvented cylinder installation, your questions

Unvented vs a combi?
Two showers running at once is the deciding question. Combis serve one outlet well; a cylinder serves the whole house simultaneously. Big household, more than one bathroom, cylinder wins.
What does it cost?
From £1,450 fitted replacing an existing cylinder; full conversions from vented (removing tanks, upgrading pipework) £2,500–£4,000. Fixed after survey.
Why does mine dribble from an outside pipe?
The discharge pipe running means a safety valve is passing, commonly the expansion vessel has lost its charge. It's the system telling you it needs its annual service; ignore it and the next part to fail is pricier.
24 hours · 365 days · London

Water where it
shouldn't be? Call.

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020 3674 8514

Or WhatsApp 07865 292684, photos help us bring the right parts

Our engineers