Gas Safe registered
TW9 TW10 TW1 TW2
Gas Safe and G3 qualified engineers across TW1, TW2, TW9 and TW10, 24 hours a day.
Answered 24 hours a day by a technical customer service member.
More houses here run an unvented cylinder than anywhere else on our list, and that changes the fault list entirely.
No heating or hot water right now? Call 0203 868 6134. We will tell you the earliest realistic slot rather than the one you want to hear.
Two details to start. Add your postcode and whether there is a cylinder in an airing cupboard and we can usually tell you the likely part before we attend.
We cover Richmond, and the whole of London
Tell us the address and you will get an honest answer about timing.
View areas we coverThree steps. The first one usually tells us most of it.
If a repair is not worth doing, we will say so on the phone. Call 0203 868 6134.
Almost nobody says they live in TW9. They say Richmond Hill, or St Margarets, or Strawberry Hill.
Names we hear on TW1, TW2, TW9 and TW10 calls, and the postcodes around them
Grouped by postcode, because that is the one part of an address everybody knows.
We work right across London, north and south of the river. If yours is not here, ring and tell us the address.

Which added four safety components most houses do not have.
Georgian around the Green and the Hill, Victorian villas through St Margarets and Twickenham, and a great deal of it listed or in a conservation area. What sets TW apart is not the age of the houses, it is what happened inside them. The loft tanks came out early here, and the vented cylinders were replaced with unvented ones running straight off the mains.
That adds parts, and the parts are what fail. An unvented cylinder carries an expansion vessel, a pressure relief valve, a tundish and a thermal cut-out. None of those exists on a vented system, and every one of them is a component with a service life shorter than the tank it protects.
The expansion vessel is the one we replace most. It holds a cushion of air that absorbs the expansion as the water heats, and over a few years that charge leaks away. With nowhere for the expansion to go, the pressure relief valve opens and you get water at the tundish. Nothing is wrong with the boiler and nothing is wrong with the cylinder. It is a vessel, and recharging or replacing it is a fraction of either.
Water at the tundish is not a leak and it is not a nuisance. It is a safety device doing its job, which means something upstream of it has already failed. Capping it off is unlawful as well as dangerous, and anybody who offers to is telling you something about their qualifications.
The commonest call from TW9, and it is rarely the boiler.
On a stored system, heating that works and hot water that does not points at the cylinder side. Three usual culprits: the motorised valve that diverts flow to the tank, the cylinder thermostat, and the immersion element. Each costs a fraction of a new appliance and each gets mistaken for one.
On an unvented cylinder there is a fourth, and it is the one most often missed. A thermal cut-out that has tripped will leave you with heating and no hot water at all, and it will not reset itself. It trips for a reason, so the job is finding why rather than pressing the button and leaving.
An unvented cylinder is a pressurised store, so working on one is notifiable and needs a G3 qualification on top of Gas Safe registration. Plenty of firms hold one and not the other, which is why a cylinder call so often becomes two visits. Our engineers hold both, so it is one visit and one charge. See unvented cylinder repair.
On an unvented system it goes for the coil.
London water comes off the Thames and the Lea, both of which run through chalk. It measures roughly 277 milligrams of calcium carbonate per litre, and that figure is much the same across the city.
Where it lands is what differs. In a combi it furs the plate heat exchanger and the hot water goes lukewarm. On an unvented cylinder in Richmond or Twickenham it lands on the coil inside the tank, insulating it from the water it is meant to be heating, so the tank takes longer and longer to recover between baths. That is a scaling problem, not a failing appliance, and it gets diagnosed as a failing appliance constantly.

Age does not decide it. The failed part does.
A pump, a diverter valve, a thermostat or a fan is a repair on almost any appliance, whatever its age. A failed main heat exchanger on a boiler well past ten years is the point where the arithmetic stops working, and we will tell you that rather than sell you the repair.
On an unvented system the replacement question needs one answer first: whether the cylinder or the boiler actually failed. They are two appliances with two service lives, and a cylinder with a flat expansion vessel will empty a brand new boiler's warranty period without either of them being at fault. In a listed or conservation-area house the flue position is the other question worth settling before anything is ordered.
Our boiler replacement page sets out what a replacement actually involves, including what changes when a stored system is converted, and the costs guide explains what moves the figure.
That answer costs nothing. It is the one most people ring us for. Call 0203 868 6134.
Next door to here we cover Putney and Barnes and Esher, Claygate and Thames Ditton. Everything else is on boiler repair in south London and areas we cover.
These are where we work most, not a boundary. An engineer attends anywhere in north London and south London. Tell us where you are and we will say plainly when we can get to you.
Dripping from a pipe outside?
On an unvented cylinder that is the tundish, and it means a safety device has operated. Turn the boiler off, ring us, and do not let anybody cap it off.
If you smell gas: do not touch any switches. Open the windows, leave the property, then call the National Gas Emergency Service on 0800 111 999. That line is free and open 24 hours. Call them before you call us.
If a carbon monoxide alarm is sounding: get everyone out immediately, then call 999 if anyone feels unwell. Do not go back in until the property has been ventilated and checked.
If the boiler locks out repeatedly: try one reset. If it locks out again straight away, stop. Repeated resets hide a fault that is still there, and on a gas appliance that is not a risk worth taking.
Under the Gas Safety (Installation and Use) Regulations 1998, only a Gas Safe registered engineer may work on gas appliances. Never open the boiler casing yourself.
Yes. The names listed above are the ones we hear most, and they are nowhere near a complete list. We work right across London, north and south of the river. Ring and tell us the address and you will get a straight answer about timing.
That is the tundish, and it means a safety device on your unvented cylinder has operated. Most often the expansion vessel has lost its air charge, so the expanding water has nowhere to go and the pressure relief valve opens. Turn the boiler off and ring. It is an emergency, and it must never be capped off.
Usually not. It is the coil inside the cylinder, furred with scale, insulating it from the water it is meant to be heating. The boiler is putting out the same heat and less of it is arriving. A service with a scale reducer fitted is what stops it getting worse.
Because an unvented cylinder is a pressurised store and the work is notifiable. It needs a G3 qualification on top of Gas Safe registration. Plenty of firms hold one and not the other, which is why a cylinder call often turns into two visits from two trades. Our engineers hold both, so it is one visit and one charge.
Yes, and every other major make, including the ones most firms will not touch. Those two are the ones we open most in TW9 and TW10. Alpha, Main, Ariston and Ferroli all turn up in the flats and smaller terraces. If your boiler is showing a fault code, the brand pages explain what it means for your make.
Yes, and on the same visit where the appliance passes, so a let property is not off the market twice. See landlord gas safety certificates. If the flat has no gas supply we cover electric boilers as well.
Yes. The rate is agreed on the phone before anybody sets off, and the engineer gives you a written breakdown of the fault, the part and the labour before any repair begins. Nothing goes ahead until you have seen it. Our costs guide sets out what drives the figure.
The line is answered 24 hours a day by a technical customer service member, not a call centre reading from a script. In the middle of the night we will tell you honestly whether it is a tonight job or a first thing in the morning job.
Every major make, and the fault code pages often name the part before you ring.
The houses that run a cylinder use system boilers, and here the ones we open most are Worcester Bosch, Vaillant and Viessmann, with Potterton still common on anything installed before the unvented conversions went through.
We also work on the makes most firms will not. Alpha, Main, Ariston and Ferroli all turn up in the flats and the smaller Twickenham terraces, and parts for every one of them are still obtainable.
If your boiler is showing a code, the make decides what it means. A Vaillant F75 and a Worcester Bosch EA are different faults with different fixes, and neither of them on its own means a new boiler. Each brand page lists the codes for that make and what actually causes them.
The full list is on our boiler brands page, and general repairs are on boiler repair in London.
Tell us where you are and whether there is a cylinder in an airing cupboard. With those two answers we can usually name the likely part, give you the rate, and book somebody in, all on the one call.
Gas Safe registered. Unvented cylinder qualified. Parts guaranteed for a year. Covering London, north and south of the river, 24 hours a day.