An unvented hot water cylinder is the sealed, mains pressure system that gives you a strong shower without a cold tank in the loft. It is also one of the few jobs in a house that it is illegal to carry out without a specific qualification. Under Part G of the Building Regulations, any unvented cylinder over 15 litres must be installed by someone holding a current G3 certificate, and that certificate has to be kept in date rather than earned once and forgotten.
Lloyd holds a current G3 qualification alongside Gas Safe registration. That is worth checking before you let anyone touch a cylinder, because an unvented system fitted by someone without it is both a breach of the regulations and a fast way to void the manufacturer warranty on a expensive piece of kit.
Unvented, vented, or leave it alone
Unvented is not automatically the right answer. It needs enough incoming mains pressure and flow to be worth doing, and if your main cannot deliver, a sealed cylinder will disappoint you no matter how good the installation is. Homes with a lot of bathrooms, or a poor shower off a gravity system, are usually the ones that benefit most.
The honest version is that some homes are better off with a vented cylinder, some with a properly sized unvented one, and a few are better served by a different type of boiler altogether. You get told which of those you are, including when the answer is that the cylinder you already have is fine and does not need replacing.
What is included, and why there is no price on this page
There is no cylinder price list here, on purpose. Cylinder work varies far too much for a number invented on a web page to be right: the size and type of unit, the pressure and flow you actually have, where the cylinder sits, the pipework and controls around it, and what is discovered once the old one comes out. A figure published here would only ever be wrong in one direction or the other.
What you get instead is the same process as every other LMB job. Send a message on WhatsApp to 07712 646488 with your postcode and a photo of the existing cylinder or airing cupboard, and you get a straight answer about what is realistic, then a fixed written quote before anything starts. The installation is notified to Building Control as the regulations require, the old unit is taken away, and the work is backed by 207 public Google reviews at a straight 5.0.
