Boiler Service Before Winter: Book Early | CAF Heating

The best time to book a boiler service before winter is late summer or early autumn - June to September. Your boiler gets checked and any faults fixed while engineers still have open diaries, so when the first cold snap arrives your heating works instead of joining the breakdown queue.

We have been servicing boilers across Surrey and South London since 1996, and every year follows the same script. September and October are calm. Then the first properly cold week lands - usually late November or early December - and the phone does not stop. Most of those calls are breakdowns that an £85 annual service a couple of months earlier would have prevented. Below, we cover why booking early beats waiting, what a pre-winter service catches, and what to do if your boiler has already given up.

What happens when everyone waits for the cold snap

Most boilers in the UK sit idle, or run hot water only, from roughly April to October. Then one cold Monday morning, hundreds of thousands of heating systems get switched on within the same 48 hours. Seals that dried out over summer start weeping, seized valves refuse to move, and ignition components that were marginal in March fail outright. A percentage of those boilers will not start at all - and every one of those households phones a heating engineer the same week.

That is why engineer availability collapses in the first cold week. A firm that could offer you a next-day service slot in August is suddenly triaging no-heat emergencies, and routine work gets pushed back two or three weeks. If your breakdown needs a part, winter demand can stretch delivery times too, so a fault that would have been a same-week fix in September can mean days without heating in December.

On cost, a planned annual service with us is a flat £85, booked at a time that suits you - you can see every price on our pricing page. An emergency breakdown visit in peak winter costs more: across the UK, out-of-hours and emergency call-out rates typically run well above standard hourly rates, and that is before any parts and repair labour on top. You are paying a premium for urgency that a £85 service in autumn would have made unnecessary.

• ◆Waiting costs you choice: in September you pick the appointment slot, in December you take whatever is left
• ◆Waiting costs you money: planned £85 service versus emergency call-out plus repair at winter rates
• ◆Waiting costs you comfort: a mid-winter breakdown can mean days without heating or hot water while parts arrive
• ◆Waiting can cost you your warranty: most manufacturers require a logged annual service, and a missed year can void cover exactly when you need it

Winter breakdowns a pre-winter boiler service catches

A good engineer uses a service to look for the failure modes that show up when a boiler goes from summer idleness to running hard every day. These are the winter breakdowns we get called to most, and the pre-winter check that heads each one off.

None of these checks are exotic - they are part of a proper annual service done at the right time of year. If you want the full item-by-item breakdown of the visit, we have written up exactly what a boiler service includes. Finding a weeping expansion vessel in September is a scheduled fix, while finding it in January is a family with no heating.

Landlords: get the CP12 and service done together before tenant heating season

If you let a property with gas appliances, you already need an annual gas safety check by law - the Health and Safety Executive sets out the landlord duties, including the annual check and giving tenants a copy of the record within 28 days. But a CP12 is a safety inspection, not a service. It confirms the appliances are safe to use; it does not strip, clean and test the boiler the way a service does. A boiler can pass its gas safety check in October and still break down in December.

That is why we tell every landlord the same thing: book the CP12 and the boiler service together in one visit, before your tenants switch the heating on. We charge £155 for the bundle - against £85 each separately - and you get one appointment to arrange with the tenant instead of two. The timing matters more for landlords than anyone: a breakdown in a tenanted property is urgent by definition, you are paying winter emergency rates to fix it, and your tenants are cold in the meantime. Getting both jobs done in late summer means the certificate is fresh, the boiler is proven, and your compliance and your heating season are both sorted in one go. Our landlord service also includes automatic renewal reminders so the anniversary never creeps up on you.

Month-by-month guide: when to book your annual service

There is no wrong month to service a boiler - once a year is the rule, whenever that falls. But if you have the choice, some months work much harder for you than others. We have covered the case for a summer boiler service in detail before; here is the whole year at a glance.

One more reason not to drift past your service anniversary: efficiency. A well-maintained boiler burns less gas for the same heat, and with heating making up the biggest share of most household energy bills - the Energy Saving Trust has plenty of guidance on cutting heating costs - going into winter with a tuned boiler is one of the simpler wins available.

What to do if your boiler does fail mid-winter

Sometimes the timing beats you - you have just moved in, the boiler was fine last week, or life got in the way. If your heating dies in the middle of a cold spell, work through this before you panic:

• ◆Check the basics first: boiler pressure (should typically sit around 1 to 1.5 bar when cold), the thermostat and timer settings, and whether the display shows a fault code
• ◆In freezing weather, check the condensate pipe - if the white plastic pipe outside has frozen, carefully thawing it with warm (never boiling) water often brings the boiler straight back
• ◆Try our step-by-step guide to what to do when your boiler stops working before paying for a call-out you might not need
• ◆If you smell gas at any point, stop - call the National Gas Emergency Service on 0800 111 999 immediately, before calling anyone else
• ◆For any repair, only ever use an engineer on the Gas Safe Register - it is illegal for anyone else to work on gas appliances in the UK

And if you would rather never gamble on winter availability again, our Service Agreement at £240 a year covers the annual service, the CP12 where needed, and priority call-out - which means when that first cold week chaos hits, agreement customers go to the front of the queue.

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