4.6 Google reviews
Open 24 hours, 7 days Rates agreed before we start Gas Safe registered
Gas Safe registered
ASAP Boiler Repairs engineer carrying tools through a hallway

Book a call out

Book a Boiler Engineer, London

Fill in the form and a technical member of the team rings you back, at any hour.

Book an engineer

Four quick details, then the make and the fault code if you have them. Those last two are what let us name the likely part before we attend.

No obligation, and no visit is booked until you have agreed the rate on the phone.

We use your details only to respond to your enquiry. See our privacy policy.

Call 0203 868 6134

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

Most bookings move faster when those two details arrive with them, because the part can be picked before anybody is dispatched.

  • 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
  • "Took his time to listen to my concerns hence it was a nice job. Thank u so much"

    Frank E.

  • "He was very professional tidy and polite. Would recommend!"

    Anna M.

  • "These guys provide an excellent service. A pleasure to deal with and professional"

    Day Walker

ASAP Boiler Repairs engineer explaining a boiler diagnosis to a homeowner

What happens after you send it

Three steps, and the first is a person, not an automated reply.

  1. Somebody rings you backNot a confirmation email saying we will be in touch. A technical member of the team calls, asks what has stopped, and works out the likely fault while you are on the phone.
  2. The likely part, and a realistic slotWe 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.
  3. The engineer attends and nothing starts until you agreeA full diagnostic first, then the fault, the part and the labour in writing. Nothing proceeds until you have seen it. Parts we fit are guaranteed for a year.

We would rather tell you tomorrow morning than promise you tonight and fail to turn up. A booking here is a slot in a real diary, not a lead passed to whoever is free. If we cannot make the time you need, you are told while you can still ring somebody else.

What it will cost, answered honestly

The question everybody has and nobody asks.

You are probably wondering whether booking commits you to anything. It does not. Nothing is charged for the call, nothing is charged for the advice on the phone, and no engineer is sent until the rate is settled with you first.

What the figure depends on is the part, not the postcode and not the hour of the day. A sensor and a heat exchanger are different jobs on the same boiler. That is why we work out the likely part on the phone first, and our guide to boiler repair costs sets out what moves it.

And if it is not worth repairing, we will tell you that on the phone rather than after we have charged you to attend. There is nothing to pay for being told.
Did you know

The bookings resolved in one visit are the ones that arrived with the make and the fault code in the message. With those two the part is often on the van before the engineer sets off. Without them it is sometimes a diagnosis on the first visit and a repair on the second, which costs you a morning.

What to have ready before you ring

None of it is required. Each shortens the call, and the last two often decide one visit or two.

The make. On the front of the boiler, usually across the bottom of the casing. Fault codes are not shared between manufacturers, so an F28 on one make and an F28 on another are different faults with different parts behind them. Every make we work on is on our boiler makes we repair page, each with the codes it actually throws.

The model. Behind the front flap, on a sticker, usually with a serial number beside it. It tells us which version of a part is fitted, and there are often three for the same component across one range.

The fault code on the display. Write it down exactly, including the letter and any full stop. F.75 and F75 are the same fault on some makes and not on others.

Whether you have a hot water cylinder. An airing cupboard with a tank in it changes the diagnosis, because the fault may not be in the boiler at all.

If it is an electric boiler, say so on the call. No flue, no gas and no combustion, so the fault list is a different one entirely. That work is covered on our electric boiler repair page.

Not sure what any of that means?

Describe what it is doing in your own words. Working out the rest is our job, and whoever answers is technical rather than a message taker.

Call 0203 868 6134

When to ring instead of booking

Four situations where the form is the wrong tool.

  • You smell gas, or a carbon monoxide alarm is sounding. Do not use this form. Use the numbers in the safety section below, and do it now.
  • There is no heat and somebody vulnerable is in the house. A baby, anyone elderly, or anyone whose health is affected by the cold. Say so and it moves you up the day.
  • Water is coming from the boiler or a cylinder. Switch it off, isolate the supply if you can reach the valve, and ring. That is emergency boiler repair, not a booking for next week.
  • It is the middle of the night and you need to know either way. The line is answered at any hour by somebody technical, who will tell you honestly whether it is a tonight job or a morning one.
Everything else is fine by form. Annual services, certificates, quotes, a fault that is annoying rather than urgent, and anything you would rather put in writing. To email or send photographs instead, contact a boiler engineer in London.

Booking a repair when it might need replacing

You do not have to decide before you ring. That is the point of the first call.

The honest answer depends on three things, and none is age on its own. A fifteen year old boiler with a failed sensor is worth repairing. An eight year old one with a corroded heat exchanger and a discontinued part may not be. The third is what is next: one expensive component failing usually means the ones beside it are the same age.

You get that assessment on the phone before anybody is sent, and you get it against us where that is the truth. Where replacing is the sensible answer, boiler installation in London sets out what is involved. Where the boiler has years left in it, you will be told that instead.

Two things extend a boiler's life more than anything else, and both cost less than a repair. An annual boiler service catches scale on the plate exchanger while it is still a clean rather than a replacement. Where the radiators are cold at the bottom or the boiler is noisy on firing, a power flush clears the sludge grinding the pump down.

Booking on behalf of a tenant? Say so and we will arrange access directly with them. The landlord gas safety certificate can be done at the same visit, saving a second appointment.

If it is the hot water rather than the heating

Say on the booking whether there is a cylinder. It changes which engineer comes.

If the radiators are fine and the hot water is not, the boiler is often working perfectly. In a house with an airing cupboard tank the fault is frequently in the cylinder or its controls: a failed immersion, a motorised valve that has stopped moving, a thermostat strapped to the tank reading nothing useful.

Unvented cylinders need a separate G3 qualification, and that is law rather than preference. An engineer without it cannot touch the safety devices on the tank, which means a wasted visit and a second appointment. That is why the booking asks about a cylinder, and why unvented cylinder repair is its own job rather than an afterthought.

Did you know

London water runs at roughly 277 mg per litre of hardness, because the Thames and the Lea both come off chalk. The first thing it scales is the plate heat exchanger that makes your hot water, so the hot water goes lukewarm and unpredictable while the heating stays perfect. It reads as a dying boiler. It is usually one part, cleaned or changed on a single visit.

Google Reviews
  • "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

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

    Graziano B.

Local boiler repair specialists

Clear advice. Careful repairs. Family-friendly service.

Call 0203 868 6134

Are you in our area?

London, north and south of the river. Every borough, no conditions.

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.

If your district is not shown, that is not a no. It is somewhere we have not written up yet. We work across north London and south London, and the full list is on areas we cover.
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.

Booking FAQs

How soon will somebody get back to me?

The line is answered 24 hours a day by a technical member of the team, and the form reaches that same team. Either way a person rings you back, not an automated reply. We deliberately do not publish a fixed number of minutes, because a firm promising the same response to everybody who contacts them is making that promise to the person before you as well. If you have no heat and cannot wait, treat it as emergency boiler repair and ring.

Does booking commit me to anything?

No. There is no charge for the call, no charge for the advice on the phone, and no engineer is sent until you have agreed the rate. If the honest answer turns out to be that the boiler is not worth repairing, we will tell you that on the phone and there is nothing to pay for being told. Our guide to boiler repair costs explains what actually drives the figure.

What should I have to hand?

Four things: your name, a number, the postcode and what you need. The make and the fault code are optional, and they are the two that matter most, because with both the right part is often on the van before the engineer sets off. That is the difference between one visit and two. Each make throws its own codes, set out on our boiler makes we repair page.

Can I book out of hours, or at a weekend?

Yes. The line is open at any hour including weekends and bank holidays, and the rate is agreed with you before anybody sets off, at three in the morning exactly as at three in the afternoon. If the job can safely wait until normal hours we will say so, because paying an out of hours rate for something that could wait until Tuesday helps nobody. See emergency boiler repair for what changes overnight.

Can you tell me whether it is worth repairing before anybody attends?

Usually yes, at least well enough to decide. Give us the make, the model and the fault code and we can tell you on the phone whether the likely part is a cheap one or one of the expensive three, and whether it is still available for that model. Age on its own decides nothing: a fifteen year old boiler with a failed sensor is worth repairing and an eight year old one with a corroded heat exchanger may not be. Where replacing is the sensible answer, boiler installation in London sets out what is involved.

The heating works but there is no hot water. Do I still book a boiler engineer?

Book, but say on the form whether you have a hot water cylinder, because it changes which engineer is sent. If the radiators are fine and only the hot water has failed, the fault is often not in the boiler at all: in a house with a tank it is frequently the immersion, a motorised valve or the cylinder thermostat. Unvented cylinders need a separate G3 qualification by law, so unvented cylinder repair is booked as its own job rather than added to a boiler call.

Can I book a service or a landlord certificate here rather than a repair?

Yes, and both are on the list in the form. Choose the one you need and the call back will be scheduled rather than treated as a breakdown. An annual boiler service and a landlord gas safety certificate can be carried out on the same visit where the property needs both, which saves a second appointment and a second access arrangement with the tenant.

Tell us the make when you book

Each throws its own codes, and each page sets out what they mean.

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.

  • "Steve was very helpful and responsive"

    Richard E.

  • "Engineer excellent and very time efficient."

    Fiona G.

Or just ring us

Have the model number and the fault code ready if you can. With those two pieces of information we can usually tell you what has failed and what it will take to put right before anybody is booked in.

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

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