SE21 SE22

Boiler Repair in Dulwich

Gas Safe engineers across SE21 and SE22, 24 hours a day.

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

What is the boiler doing?

If the boiler is in a utility on an outside wall or an outbuilding, the condensate is the first thing we ask about in winter.

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

"Efficient and amiable service all round. Even managed to save me money by fixing a thermostat that we thought was broken."
Graziano B.
"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.

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 Dulwich, 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 SE21 and SE22 it is nearly always yes. The other thing worth telling us in winter is where the boiler sits, because that decides whether the condensate can freeze.
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 SE21. They say the Village, or East Dulwich, or Lordship Lane.

Names we hear on SE21 and SE22 calls, and the postcodes around them

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

SE21Dulwich Village, West Dulwich, Sydenham Hill and College Road
SE22East Dulwich, Lordship Lane, Peckham Rye and North Dulwich
SE24Herne Hill and Half Moon Lane
SE23Honor Oak and Honor Oak Park
SE15Nunhead and Peckham Rye east

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

The boiler is often not in the house

Which is fine until the first hard frost.

Dulwich is large detached and semi-detached houses on generous plots, most of them with a cylinder and a good number with the plant somewhere other than a kitchen cupboard: a utility on an outside wall, a converted garage, or an outbuilding across a side passage. That is a sensible place for a boiler and it introduces one seasonal weakness. Every condensing boiler produces acidic water, and it has to run somewhere. Where the appliance sits against an outside wall or in an unheated outbuilding, that pipe runs outside or through cold air, and in a hard frost it freezes. The boiler detects that it cannot clear the condensate and locks itself out to avoid flooding. So the classic Dulwich winter call is a boiler that was perfect at bedtime and dead in the morning, showing a lockout code, on the coldest night of the year. Nothing has broken. Thawing the pipe restores it in twenty minutes, and lagging or re-routing it properly stops it happening every winter.

Did you know A condensate pipe that freezes once will freeze again, because the fault is its route and its diameter rather than the weather. Re-running it in wider pipe, insulating it, or bringing it inside to an internal drain is a permanent fix and costs a great deal less than a call-out every January.

Heating fine, hot water gone

The commonest call from SE21, 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. Where the plant is in an outbuilding there is a fourth thing worth checking, and it is the buried flow and return between the outbuilding and the house. If that was laid without proper insulation it loses heat all the way, so the cylinder never quite reaches temperature and the boiler runs far longer than it should to get there. 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 Dulwich house that kept its cylinder it lands on the coil inside the tank, so the tank takes longer and longer to recover between baths. Same water, different part, and a scaled coil reads as a failing boiler often enough that boilers get condemned for it.

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

"Steve was very helpful and responsive"
Richard E.
"These guys provide an excellent service. A pleasure to deal with and professional"
Day Walker
"Engineer excellent and very time efficient."
Fiona G.

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. Where the plant is in an outbuilding, the replacement question carries a second one: whether the buried flow and return between there and the house is still fit to keep. A new appliance at the end of a poorly insulated underground run will waste a good part of what it makes, and no amount of efficiency rating changes that. 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 Sydenham and Forest Hill and Herne Hill and Brixton. Everything else is on boiler repair in south London and areas we cover.

Ealing and NorthfieldsLarge Edwardian houses, zoned heatingView services Richmond and TwickenhamUnvented cylinders are the normView services Putney and BarnesHouses and mansion flats mixedView services Notting Hill and Holland ParkStucco terraces, plant in the basementView services CroydonTown centre flats to Shirley detachedView 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.

Boiler dead after a cold night?

If it went off overnight in a freeze and shows a lockout, the condensate has very likely frozen. It is often a twenty minute fix and sometimes free. Ring before you book anything bigger.

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 Dulwich?

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.

The boiler was fine last night and is dead this morning. It was freezing. What is that?

Almost certainly a frozen condensate pipe. Every condensing boiler produces water that has to run away, and where that pipe goes outside or through an unheated space it freezes in a hard frost. The boiler locks itself out rather than flood. Thawing it restores the boiler in about twenty minutes, and it is not a breakdown.

Will it just freeze again next winter?

Yes, unless the route is changed, because the cause is the pipe rather than the weather. Re-running it in wider pipe, insulating it properly or bringing it to an internal drain is a permanent fix and costs far less than a call-out every January.

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. All three cost a fraction of an appliance. Our unvented cylinder repair page explains what is involved.

The boiler is in the garage and the house takes ages to warm up. Why?

Often the buried flow and return between the outbuilding and the house. If it was laid without proper insulation it loses heat the whole way, so the cylinder never quite reaches temperature and the boiler runs much longer than it should. That is worth measuring before anybody blames the appliance.

Do you repair Worcester Bosch and Vaillant boilers in Dulwich?

Yes, and every other major make, including the ones most firms will not touch. Those two are what we open most in SE21 and SE22. Ariston, Ferroli, Vokera, Biasi, ATAG and Keston all turn up here as well. If your boiler is showing a fault code, the brand pages explain what it means for your make.

I am a landlord with a flat in SE22. 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. On a freezing night that matters, because a frozen condensate is usually a quick fix and we would rather tell you that on the phone than sell you a morning appointment.

The makes we see most in SE21

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

The large houses run system boilers feeding a cylinder, and here the ones we open most are Worcester Bosch, Vaillant and Ideal, with Viessmann on anything specified recently. The flats and conversions around Lordship Lane run combis. We also work on the makes most firms will not. Ariston, Ferroli, Vokera, Biasi, ATAG and Keston all turn up in SE21 and SE22, and parts for every one of them are still obtainable. If your boiler is showing a code, the make decides what it means. A frozen condensate shows as a different code on a Worcester Bosch than on a Vaillant, and on both it means the same simple thing. 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

"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.
"Very professional and would recommend to anyone!"
Abby M.
"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

Book an engineer in Dulwich

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.