SW4 SW11

Boiler Repair in Clapham and Battersea

Gas Safe engineers across SW4 and SW11, 24 hours a day.

Answered 24 hours a day by a technical customer service member.

What is the boiler doing?

A great many of these houses were flats once and are houses again, and the heating still shows it.

Gas Safe registered engineers
An engineer as soon as we can, booked around you
Cylinder and unvented systems as well as combis
Parts guaranteed for a year, rates agreed before work starts

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.

Google Reviews

"He was very professional tidy and polite. Would recommend!"
Anna M.
"Took his time to listen to my concerns hence it was a nice job. Thank u so much"
Frank E.
"Very polite and respectable engineer...had two other heating company that struggle to find the issue with my boiler but ASAP repaired it on the same day thanks absolute life saver"
JA Morris

Prefer we call you? Request a call back

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 Clapham, and the whole of London

Tell us the address and you will get an honest answer about timing. View areas we cover

What happens when you call

Three steps. The first one usually tells us most of it.

Tell us where you are and whether there is a cylinderIn SW4 and SW11 the more useful question is often whether the house was ever divided, because the heating that came out of a conversion behaves differently.
You will know what has probably failed, and when we can comeWe tell you the likely part and a realistic slot. If we cannot reach you today we say so on the phone, rather than after you have waited in.
Nothing starts until you have agreed the costThe engineer runs a full diagnostic, then puts the fault, the part and the labour in writing. Parts are guaranteed for a year.

If a repair is not worth doing, we will say so on the phone. Call 0203 868 6134.

We come to every street around here

Almost nobody says they live in SW4. They say the Old Town, or Abbeville, or just off the Common.

Names we hear on SW4 and SW11 calls, and the postcodes around them

Grouped by postcode, because that is the one part of an address everybody knows.

SW4Clapham, Clapham Common, Clapham Old Town, Abbeville Village, Clapham North and Clapham South
SW11Battersea, Battersea Park, Queenstown Road, Nine Elms and Clapham Junction
SW8Stockwell, South Lambeth and Wandsworth Road
SW9Brixton and Stockwell border
SW12the Balham and Nightingale Lane border

We work right across London, north and south of the river. If yours is not here, ring and tell us the address.

Most of these houses were flats once, and are houses again

The heating is usually the last thing to catch up.

SW4 and SW11 have been through two full cycles. The whole Victorian houses around Clapham Common and off Northcote Road were divided into flats through the sixties and seventies, and over the last twenty five years a great many have been put back together as single homes. Nowhere else on our list has done that at the same rate. What a de-conversion leaves behind is a patchwork. Two heating systems joined into one, sometimes with the second boiler still sitting in a cupboard doing nothing. Radiators fed from whichever circuit was nearest at the time. And, almost always, dead legs: lengths of old flow and return capped off inside a ceiling or a wall rather than removed. Dead legs matter more than they sound. Air collects in them and cannot be bled out, sludge settles in them and washes back into the system, and they make a house impossible to balance properly because part of the circuit goes nowhere. It shows up as one or two radiators that have never worked properly since the building work, and it gets blamed on the boiler.

Did you know If a house was ever two flats, check whether there are still two gas meters. It is surprisingly common to find a capped second supply, and it is worth knowing about before anybody starts moving an appliance.

Heating fine, hot water gone

The commonest call from SW4, 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. In a de-converted house there is a fourth. Where two systems were joined, the hot water may still be running through controls from the original upstairs flat, wired to a programmer nobody has looked at in fifteen years. The fault is a control, in a cupboard, and it is invisible from the boiler. 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.

Water running from a pipe outside? If it comes from a tundish, the cylinder is discharging and a safety device has failed. Turn the boiler off, isolate the cold feed if you can find the stopcock, and call. That is an emergency, not a booking for next week.

What hard water is doing to your boiler

The one thing a yearly visit genuinely prevents.

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. In a whole Clapham house that kept its cylinder it lands on the coil inside the tank. In a de-converted house it does something else as well: old pipework that has sat unused for years holds sludge, and the first proper cold snap washes it straight into the new part of the system.

Two parts stop it, and they do different jobs. A scale reducer on the mains protects the hot water side. A magnetic filter on the return catches the magnetite that blocks exchangers and seizes pumps. Both go in during a yearly service, and a power flush deals with what is already in there.

Google Reviews

"These guys provide an excellent service. A pleasure to deal with and professional"
Day Walker
"Steve was very helpful and responsive"
Richard E.
"Efficient and amiable service all round. Even managed to save me money by fixing a thermostat that we thought was broken."
Graziano B.

Repair or replace

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. SW4 asks the replacement question more than most areas, usually during building work, and that is exactly when it is worth asking properly. A new appliance dropped onto a de-converted system with dead legs and two sets of controls will inherit every one of those problems. Putting the system right first is a fraction of the cost and it decides whether a replacement is worth anything. 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.

Nearby areas

Next door to here we cover Herne Hill and Brixton and Balham and Wandsworth Common. Everything else is on boiler repair in south London and areas we cover.

Notting Hill and Holland ParkStucco terraces, plant in the basementView services Hampstead and Belsize ParkLarge Victorians, stored hot waterView services Putney and BarnesHouses and mansion flats mixedView services Fulham and Parsons GreenTerraces and mansion flatsView services DulwichLarge detached, cylinders standardView services All areasEvery area we have written upView all

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.

Radiators that never made sense?

In a house that was flats and is a house again, that is usually old pipework nobody removed. Tell us which ones are cold and we can normally say what is behind them.

Call 0203 868 6134

Safety

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.

Common questions

Do you cover my street in Clapham?

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.

Two radiators have never worked since the building work. Why?

Usually because the circuit feeding them was left half connected. When a house that was flats becomes a house again, old flow and return is often capped off inside a ceiling rather than removed. Those dead legs trap air and sludge and make the system impossible to balance. It is a pipework job, not a boiler job.

My radiators are hot but there is no hot water. Do I need a new boiler?

Almost certainly not. That points at the cylinder side: the motorised valve that diverts to the tank, the cylinder thermostat, or the immersion element. In a de-converted house it can also be a control left over from the original upstairs flat. Our unvented cylinder repair page explains what is involved.

There is a second boiler in a cupboard that nobody uses. Is that a problem?

Not in itself, but it should be properly isolated rather than simply switched off, and if it is still connected to a gas supply that needs capping correctly. It is also worth checking whether there is a second gas meter, because a capped supply from the flat days is common here.

The whole system is being redone. Should the boiler go at the same time?

Not automatically. Age alone does not decide it. If the appliance is sound, the money is usually better spent removing dead legs, rebalancing and fitting a magnetic filter, because those are what a new boiler would otherwise inherit.

Do you repair Worcester Bosch and Vaillant boilers in Clapham?

Yes, and every other major make, including the ones most firms will not touch. Those two are what we open most in the whole houses. Alpha, Main, Ariston, Ferroli and Vokera all turn up in the flats, and in a de-converted house two different makes in one building is normal. If your boiler is showing a code, the brand pages explain it.

I am a landlord with a flat in SW11. Can you do the certificate too?

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 it has no gas supply we cover electric boilers as well.

Are you available at night and at weekends?

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.

The makes we see most in SW4

Every major make, and the fault code pages often name the part before you ring.

The whole houses run system boilers feeding a cylinder, and the ones we open most here are Worcester Bosch, Vaillant and Viessmann. The flats that are still flats run combis, where Ideal and Glow-worm are common. We also work on the makes most firms will not. Alpha, Main, Ariston, Ferroli and Vokera all turn up, and in a de-converted house it is common to find two different makes in the same building. 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.

Google Reviews

"Engineer excellent and very time efficient."
Fiona G.
"Very professional and would recommend to anyone!"
Abby M.
"Very happy with this company very and professionally service. Fixed my leaking TRV and after draining my system and the refilled and vented the air . Thank you I have heating now"
Jamie K.

Book an engineer in Clapham

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.

Call 0203 868 6134 Book an engineer online

Gas Safe registered. Unvented cylinder qualified. Parts guaranteed for a year. Covering London, north and south of the river, 24 hours a day.