Vaillant boiler warranty check: how to find out if you are still covered

The three ways Vaillant lets you check

Vaillant calls it a guarantee rather than a warranty, so a search for a Vaillant boiler warranty check can come back empty. The two words mean the same thing here. Vaillant's registration page sets out three routes to register or check an appliance: the myVaillant Web portal, your Vaillant installer, or the service team over the phone.

Start with the installer. Vaillant says it plainly: “Please check with your installer if they have already registered your appliance.” Most guarantees are registered by the engineer who fitted the boiler, on the day, so their records are the fastest answer.

If you would rather ask Vaillant directly, the same page lists a phone number of 0330 100 3462 and a WhatsApp route to the service department. Vaillant states that its call centre is open 364 days a year, and that calls cost up to 13p per minute, with calls from mobiles varying.

Whichever route you take, Vaillant asks for the same three things: the serial number, the date of installation, and the installation address. The serial number catches people out, because it is 28 digits long.

Do not remove the boiler casing to look for it. Behind that panel is gas work, and only a Gas Safe registered engineer may go in there. If the number is not on the control panel, use the Benchmark logbook, the boiler packaging or ask your installer.

Key facts

• Vaillant needs the full 28 digit serial number, the date of installation and the installation address to look up a guarantee.
• The serial number is on the control panel, and Vaillant's terms also list the boiler packaging, the data plate, removable stickers on top of the boiler, and the back of the control box.
• Do not remove the boiler casing to look for it. Behind that panel is gas work, and only a Gas Safe registered engineer may go in there. If the number is not on the control panel, use the Benchmark logbook, the boiler packaging or ask your installer.
• Registration deadline: within 30 days of installation. Miss it and the guarantee reverts to 12 months from the date of installation.
• It runs from the date of installation, but only if you can prove that with an invoice or a completed Benchmark logbook. Without proof it runs from the earlier date of manufacture.
• An annual service by a Gas Safe registered engineer is a condition of the guarantee, and its cost is not included. It covers manufacturing defects inside the boiler, not the rest of your heating system.
• Standard length depends on the model: 5 years on the ecoTEC plus, 2 years on the ecoTEC pro and ecoFIT pure, with longer terms through Vaillant's installer scheme.

How long is a Vaillant guarantee?

There is no single answer. The standard term is set by the model, and the installer can extend it: Vaillant describes its myREWARDS scheme as open to installers who are Gas Safe registered or MCS certified. The table quotes what Vaillant publishes today on its UK product pages. Check the page for your exact model, because these figures change with the range.

Vaillant guarantee lengths as published by Vaillant

The 30 day registration rule

This is the single clause that decides most Vaillant guarantee checks. Clause 5 of Vaillant's domestic boiler guarantee terms reads: “The boiler guarantee must be registered within 30 days of installing the appliance. Failure to register within this time period will result in the guarantee reverting to 12 months from date of installation.”

So a ten year guarantee that nobody registered is a twelve month guarantee, and on a boiler fitted three years ago the check will not go your way.

Two more clauses shape the start date. Clause 4 says the guarantee commences from the date of installation, and that Vaillant requires proof of purchase to validate this, an invoice or a completed Benchmark logbook, “without which the guarantee will commence from the date of manufacture, as shown on the boiler data plate”. Clause 1 also requires installation and commissioning by a Gas Safe registered engineer within 6 months of despatch, in Vaillant's own wording.

If you bought the house with the boiler already fitted, ask the seller for the Benchmark logbook and the original invoice. Clause 3 requires that logbook to be completed by the installer at the point of installation and kept on site for inspection, so it should still be in the property.

What keeps a Vaillant guarantee valid

Registering the boiler is the start, not the finish. Vaillant's terms attach ongoing conditions, and clause 24 reserves the right to declare the guarantee null and void if they have not been complied with in full.

1. Get it serviced every year. Clause 7 says the boiler “must be serviced annually by a Vaillant or other registered Gas Safe Registered engineer in accordance with the manufacturer's instructions”. Clause 9 adds that its cost is not included, so it is a bill you pay.

2. Write it in the Benchmark logbook. Clause 8 says service details must be recorded there and the logbook must be available for inspection. A visit that is not logged is hard to prove years later.

3. Use the right engineer for repairs. Clause 12 covers material and labour on components inside the boiler against manufacturing defects, “provided the repair is carried out by Vaillant or a Vaillant authorised Gas Safe registered engineer”. Clause 13 adds that third-party invoices will not be accepted unless Vaillant pre-authorised them in writing, so calling out your own engineer first and asking Vaillant to pay afterwards does not work.

4. Genuine parts only, and leave the boiler where it is. Clause 27 says non-genuine Vaillant spare parts in any repair will invalidate the guarantee. Clause 16 says moving the boiler to another property without Vaillant's written consent will invalidate it too.

What a Vaillant guarantee does not cover

This is where a valid guarantee and a repair bill can still arrive together. Clause 10 limits the guarantee to boiler component failures and says it “does not apply to any other central heating system components external to the boiler, (such as room thermostats, time controls, motorised valves etc.)”. Radiators, pipework, valves and controls sit outside it.

Clause 17 excludes self-maintenance tasks such as re-pressurising the system, bleeding air or thawing frozen condensate pipes. Clause 18 excludes fair wear and tear, wilful damage, accidental damage, negligence, damage caused by animals, rodents, birds or pests, and failure to use the product in line with the operating instructions. Clause 15 makes the visit chargeable at the prevailing rates if the failure was caused by contaminated water in the boiler, such as limescale or sludge.

A manufacturer guarantee and a cover plan do different jobs. A Vaillant guarantee covers manufacturing defects in components inside the boiler, and clause 12 requires the repair to be carried out by Vaillant or a Vaillant authorised Gas Safe registered engineer. It does not reach the external system parts in clause 10, it excludes the self-maintenance tasks in clause 17 and sludge damage under clause 15, and it ends on the day it expires. A Smart Plan cover plan is a separate product built for future breakdowns rather than manufacturing defects, and there is a link to our boiler and central heating cover in the helpful links below. Clause 26 confirms the guarantee is in addition to, and does not affect, your statutory rights.

A boiler is a gas appliance. If you ever smell gas or are worried about gas safety, do not troubleshoot. Turn off the gas supply, do not touch any electrical switches, do not smoke, put out all naked flames, open the doors and windows, and contact the National Gas Emergency Service immediately on 0800 111 999.

Vaillant guarantee check FAQs

Vaillant out of guarantee? Build cover around the boiler you have.

Once a Vaillant guarantee expires, every breakdown is your bill, and the annual service Vaillant asked for is still a bill on top. Smart Plan is a service plan, not insurance, built from the modules you choose. Pick the boiler and central heating module and it pays parts and labour up to £500 in a 12-month period on a boiler under 7 years old, or up to £200 once it is over 7, with anything beyond that limit down to you. Call-outs on a cover plan run Monday to Friday, 08:00 to 18:00, and we aim to get an engineer out to you within two working days. In your first 30 days on the plan a £95 call-out fee applies, paid in advance. That window is Smart Plan's own and has nothing to do with Vaillant's 30 day registration deadline, and your cover still applies throughout it: the fee is the only thing that changes. The same £95 fee applies to faults the plan does not cover, no-access visits and early annual-service requests. Once you use a module a 12-month agreement period starts, and leaving early costs the remaining months or 75% of the outstanding balance. It comes from UK Boiler Company Ltd, trading since 2014.

Helpful links

• Vaillant boiler fault codes
• Vaillant help and support
• How to check your boiler warranty
• Is boiler cover the same as insurance?
• Boiler & central heating cover
• Vaillant boiler guarantee terms
• Vaillant guarantee registration
• Check an engineer on the Gas Safe Register