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Vaillant Group UK Limited (‘Vaillant’) Guarantee Terms and Conditions

To receive the full benefits of the extended guarantee the following terms and conditions must be followed or your claim will be rejected: If your installer advises you of a boiler fault, please contact Vaillant Service.

1. Installation and commissioning must be carried out by a Gas Safe** registered engineer, within 6 months of despatch of the boiler from Vaillant’s warehouse.

2. All works must be fully in accordance with the installation manual and these terms and conditions.

3. The Benchmark logbook must be completed by the installer at the point of installation and retained on site for inspection during an engineer’s visit.

4. The guarantee will commence from the date of installation. To validate this Vaillant will require proof of purchase – i.e. an invoice or completed Benchmark logbook, without which the guarantee will commence from the date of manufacture, as shown on the boiler data plate.

5. 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.To register your guarantee and for further details go to our website at:

6. To register you must provide the full 28 digit serial number of the appliance. This is clearly shown on the;

  • Boiler packaging
  • Appliance data plate
  • Removable stickers attached to the top of the boiler
  • Back of the control box

7. The boiler must be serviced annually by a Vaillant or other registered Gas Safe Registered engineer in accordance with the manufacturer’s instructions.

8. Service details must be recorded in the Benchmark logbook which must be available for inspection.

9. The cost of annual servicing is not included in the guarantee.

10. The guarantee applies only to boiler component failures and does not apply to any other central heating system components external to the boiler, (such as room thermostats, time controls, motorised valves etc.).

11. Any Vaillant article or accessory supplied other than the boiler, e.g. control, will be covered by a separate guarantee relating to that accessory.

12. The guarantee will cover material and labour charges to repair or replace components within the boiler against manufacturing defects from the installation date, provided the repair is carried out by Vaillant or a Vaillant authorised Gas Safe registered engineer.

13. Invoices for attendance and repair of this appliance by third parties will not be accepted for payment unless pre-authorised in writing by Vaillant.

14. The guarantee on any repair or replacement parts (including boiler replacement, should it be necessary) does not extend the guarantee period in relation to the appliance beyond the original term as defined in accordance with clause 5.

15. If any failure is caused by contaminated water in the boiler (e.g. blockages, or influences of flux residues, iron oxides, limescale, sludge etc.) the engineer’s visit becomes chargeable at the prevailing rates.

16. Moving the boiler to another property without Vaillant’s written consent will invalidate the guarantee.

17. Self-maintenance tasks such as re-pressurising the system, bleeding air or thawing frozen condensate pipes are not covered by the guarantee. In these instances Vaillant recommends you contact your Gas Safe registered engineer.

18. The guarantee does not include cover for fair wear and tear, wilful damage, abnormal storage or working conditions, accidental damage or negligence by you or by any third party and failure by you or any third party to operate or use the products in accordance with the operating instructions.

19. The guarantee does not cover installation in mobile leisure accommodation vehicles – i.e. boats, caravans etc.

20. The guarantee does not cover consequential losses relating to any other costs or expenses caused by or arising as a result of the breakdown of a Vaillant boiler.

21. All installation related, non-boiler or external system fault calls will be charged to you and could also invalidate your guarantee.

22. Health and safety is paramount to us and if our engineers cannot gain safe access to the boiler or an engineer cannot gain access to the property then Vaillant’s abortive charge will apply.

23. For calls requested to boilers within the guarantee period a refundable deposit may be required prior to the commencement of any works or any visit. This deposit will not be retained if the diagnosed fault is covered by the boiler guarantee.

24. If these terms and conditions have not been complied with in full then Vaillant reserves the right to declare your guarantee as null and void. Vaillant’s decision regarding guarantee claims is final.

25. If this guarantee is declared null and void, upon your request, Vaillant may offer to provide an extended guarantee product for repairs and annual services for an additional cost.

26. This guarantee is in addition to, and does not affect, your statutory rights in relation to any product that is faulty or not as described.

27. The use of any non-genuine Vaillant spare parts in any repair will invalidate the guarantee.

28. In registering the guarantee please note that Vaillant will share your personal data with its business partners in order to assist with the administration of the guarantee.

29. The guarantee is provided to you by Vaillant Group UK Limited, (registered in England with Company Registration No. 00294316) of Nottingham Road, Belper, Derbyshire, DE56 1JT.

30. The guarantee is valid for installation in domestic dwellings in the United Kingdom and the Republic of Ireland, Isle of Man and Channel Islands.

31. The terms of this guarantee are subject to the laws of England and Wales and any dispute arising from this guarantee shall be decided under those laws and before a court or tribunal in England.

Additional requirements for single or multiple boiler installations that total over 70kW

32. The boilers built-in air purge routine must be run for its full duration to eliminate air before any initial firing of the boiler following system filling or refilling. During these periods boiler flow temperature should be set no higher than 50°C.

33. The boiler must be flushed prior to first ignition to ensure that there are no impurities or contaminates within the heat exchanger.

34. Boiler installations comprising single OR multiple (smaller) boilers where the total output exceeds 70kW net then the use of a plate heat exchanger to provide system separation (achieving total separation of the boiler(s) from the pipework and heating system within the premises) is a fundamental requirement for the validity of the guarantee.

35. All water circulating within the boiler is to be checked for hardness and salinity, and must be in a clean and uncontaminated state (correctly and fully treated with corrosion inhibiter where applicable or having been treated using such other water quality regime as is consistent with good industry practice) before first ignition and maintained so throughout the boiler life cycle with details logged in the Benchmark log book. Failure to ensure the pure quality of water within the boiler side of the system will make the guarantee void and no payment will be made there under.

36. All boiler installations must be fitted with suitable disconnection facilities to gas, water, electrical and flue systems to allow our engineers to carry out any remedial works as may be required without intervention of third party specialist contractors. Should third party specialist contractors be required to carry out remedial works then the owner/occupier must arrange for these works to be carried out in co-ordination with Vaillant service at the customer’s own cost. Any such costs will not be covered by the guarantee.

37. The boiler, its controls and flue systems must be installed in full accordance with the supplied installation manual as well as all prevailing building control regulations and local regulations. The flue termination must allow for full free safe dispersal of the flue products which must not contact building surfaces or cause nuisance due to plume.

** or its equivalent body

Terms and Conditions listed here effective from 01/06/2022