When Does a New Boiler Need First Service?

A new boiler needs its first service within 12 months of the installation date. Most manufacturers set this as a firm condition of the warranty, so the clock starts ticking the day your boiler is commissioned, not the date your old boiler was last serviced. 

Some installers will even recommend an early check-in at around the six-month mark, particularly if the boiler had a slightly tricky installation or you’ve noticed anything unusual since it went in. 

Getting this timing right matters more than people expect, because missing that first service window can quietly void the very protection you paid for when you bought the boiler in the first place. Below, we’ll explain exactly how the timing works, what that first visit actually involves, and how to make sure you never lose track of it again.

When Should A New Boiler Have Its First Service?

A new boiler should have its first service within 12 months of the installation date, and this is the standard that almost every major manufacturer, including Worcester Bosch, Vaillant, Ideal, and Baxi, builds into their warranty terms. 

The commissioning date, which is the date the boiler was installed and first switched on, is what starts the clock, not the date of your previous boiler or the date you signed the paperwork for the new one.

It’s worth booking that first service a little ahead of the 12-month mark rather than right up against it, since availability can get tight in the run-up to winter when everyone else is trying to do the same thing. A good habit is to note the commissioning date somewhere obvious, like a calendar reminder or a note in your boiler’s manual, so you’re not relying on memory a year down the line.

This is exactly the kind of detail that’s easy to overlook when you’re settling into a new home or dealing with a fresh installation, which is why a lot of homeowners choose to set up an annual boiler service plan with PlusHeat from the outset. 

It takes the guesswork out of remembering dates and means the reminder lands in your inbox automatically, rather than depending on you to keep track of it yourself.

Why Does A New Boiler Need An Early First Service?

A new boiler needs an early first service mainly to protect the manufacturer’s warranty, which is arguably the single biggest reason people skip a service and later regret it. Nearly every boiler brand states clearly in their warranty documents that annual servicing by a Gas Safe registered engineer is a condition of keeping that cover valid, and this applies from the very first year, not just once the boiler is a few years old.

Beyond the warranty side, an early service also gives an engineer the chance to catch anything that might not have settled properly during installation, such as a slightly off pressure reading or a minor adjustment that’s needed once the system has been running under real conditions for a few months. 

New boilers are generally reliable, but they’re not immune to teething issues, and picking those up early is far less stressful than discovering them when the boiler stops working altogether in the middle of a cold spell.

Does Skipping The First Service Void The Boiler Warranty?

Skipping the first service can void the boiler warranty, and this is one of the most common ways homeowners unknowingly lose cover they thought they had. Manufacturers are generally strict about this condition because servicing is how they confirm the boiler is being looked after correctly, and if there’s no record of that first annual check, they’re within their rights to refuse a warranty claim even for a fault that would otherwise have been covered.

This catches people out more often with new boilers than older ones, simply because the excitement of a fresh installation means the first service slips people’s minds far more easily than a service they’ve already been doing for years. 

If your boiler develops a fault in year two or three and you can’t produce proof of that first service, you could be looking at the full repair cost yourself, on a boiler that’s still meant to be under warranty.

What Happens During A New Boiler’s First Service?

A new boiler’s first service generally follows the same process as any annual boiler service, carried out by a Gas Safe registered engineer. This includes a visual inspection for any leaks, damage, or early signs of wear, checking gas pressure and flow against the boiler’s specifications, testing the flue for safe ventilation, and running a carbon monoxide check to confirm everything is operating safely.

Because the boiler is still new, the engineer will often pay particular attention to how the installation has settled in, checking that pipework connections remain secure and that pressure levels have stayed consistent since commissioning. 

Any adjustments made at this stage tend to be minor, but they’re the kind of small tweaks that keep a boiler running efficiently for years rather than developing bigger issues later on.

Does A New Boiler Still Need A Gas Safety Check In Its First Year?

A new boiler still needs a gas safety check in its first year if you’re a landlord, and this is a separate legal requirement from the service itself. The Gas Safety (Installation and Use) Regulations 1998 don’t make an exception for newly installed appliances, so even a boiler fitted last month needs its first annual gas safety check within 12 months, resulting in the CP12 certificate you’re required to give tenants.

Homeowners aren’t legally required to have a gas safety check done, but many engineers will combine it with the first service anyway, since the two visits overlap significantly in what they cover. 

For landlords with a brand new boiler in a rental property, it’s worth diarising this alongside the service date so both obligations get met in the same visit rather than becoming two separate things to remember.

Can You Book A New Boiler’s First Service Earlier Than 12 Months?

You can book a new boiler’s first service earlier than 12 months, and in some cases it’s genuinely a good idea. If your boiler had a complicated installation, if you’ve noticed anything slightly off since it was fitted, such as unusual noises or fluctuating pressure, or if the property sat empty for a stretch after installation, an earlier check-in around the six to nine month mark can offer useful peace of mind.

There’s no downside to servicing a new boiler slightly ahead of schedule, since it doesn’t affect the warranty timeline in any negative way. What matters for warranty purposes is that a service happens at least once within each 12-month period from the commissioning date, so booking early simply resets the clock a little sooner rather than causing any issue.

What Records Should You Keep After A New Boiler’s First Service?

You should keep the service report, the engineer’s Gas Safe registration details, and the date of the visit after a new boiler’s first service, ideally stored alongside your original installation and commissioning paperwork. This combination of documents is what proves to a manufacturer that warranty conditions have been met if you ever need to make a claim.

It’s worth keeping both digital and paper copies where possible, since some manufacturers request original documentation rather than scanned copies during a warranty dispute. 

If you’re a landlord, these records sit alongside your CP12 certificate as part of the same overall compliance file for the property, which makes life considerably easier if a tenant query or a warranty issue comes up later.

How Can You Avoid Missing A New Boiler’s First Service Date?

You can avoid missing a new boiler’s first service date by setting a reminder tied directly to the commissioning date rather than relying on memory alone, since it’s an easy detail to lose track of once the excitement of the new installation has settled down. A simple calendar alert, a note from your installer, or a sticker on the boiler itself with the commissioning date written on it can all help.

The most reliable option, though, tends to be a service plan that manages the reminder for you automatically.

Book Your New Boiler’s First Service With PlusHeat

Getting that first service booked on time protects your boiler’s warranty, catches any early teething issues before they become expensive repairs, and keeps your new heating system running exactly as efficiently as it should. 

PlusHeat’s annual boiler service plans start from just £6.98 a month, with every visit carried out by a Gas Safe registered engineer and covering the full checklist, from pressure and flue checks to a carbon monoxide test and component inspection.

Booking is quick, whether online or over the phone, and once you’re set up, automatic reminders take care of the rest, so your next service is never a surprise. It’s a small, sensible step that protects the investment you’ve just made in your new boiler.

Book your new boiler’s first service with PlusHeat and keep your warranty protected from day one.

Frequently Asked Questions

Does a new boiler’s first service cost the same as later annual services?

A new boiler’s first service typically costs the same as any standard annual service, since the process and time involved are largely similar regardless of the boiler’s age. Some installers offer a discounted or included first service as part of the installation package, so it’s worth checking your original quote before booking separately.

Do combi boilers and system boilers have different first service timelines?

Combi boilers and system boilers generally follow the same first service timeline of within 12 months of installation, since this requirement comes from the manufacturer’s warranty terms rather than the boiler type itself. The specific tasks carried out during the service can vary slightly between the two types, but the overall timing expectation stays consistent.

Does moving into a property with a recently installed boiler affect the first service date?

Moving into a property with a recently installed boiler does not reset the first service date, which remains tied to the original commissioning date regardless of who owns or occupies the property. It’s worth asking the previous owner or estate agent for the installation paperwork so you know exactly when that first service is due.

Can an engineer confirm a boiler’s commissioning date if the paperwork has been lost?

An engineer can often estimate a boiler’s age and check the internal data or serial number to help confirm roughly when it was installed if the original paperwork has been lost. However, for exact warranty purposes, it’s best to contact the original installer or the manufacturer directly, as they may hold a registered commissioning record on file.

Does a boiler’s first service affect its energy efficiency rating?

A boiler’s first service does not change its official energy efficiency rating, since that figure is fixed by the manufacturer based on the appliance’s design and performance testing. However, a properly serviced boiler is more likely to perform closer to its stated efficiency in real world use, since a well maintained system loses less energy to faults or poor calibration over time.