Manufacturer Service and Maintenance Plans

A manufacturer service plan is a paid contract, sold by the maker of a boiler or cylinder or by a partner acting for it, that covers an annual service and repairs to equipment that is out of guarantee. It is not a warranty. A warranty comes with the product and protects it while it is new; a service plan is bought afterwards, usually once the guarantee has expired, and it is the annual service inside the plan that often keeps the warranty valid in the first place. Many manufacturers require an annual service in order to keep the warranty valid¹.

The distinction matters because the two obligations run in opposite directions. A warranty is the maker's promise about the product. A service plan is the household's payment for somebody to attend, service and repair. The Home Heating Industry Council's guidance is that the boiler manufacturer may give more detailed advice in its appliance instructions, and that those instructions must always be complied with to ensure the boiler warranty is protected².

Most of the plans sold under a manufacturer's name in the UK are not administered by the manufacturer at all. Worcester's plan, Vaillant's plans and EDF Energy's boiler cover are all provided by Domestic & General Services Limited³. That single fact shapes what a household is buying: a maker's brand on the paperwork, an insurer's terms underneath.

What a manufacturer service plan is and how it differs from a warranty

A warranty and a service plan are often confused because both are described in years and both involve the maker's name. The difference is who is paying and what triggers a visit.

A warranty is included in the price of the equipment and covers defined faults for a defined period, subject to conditions. The most common condition is servicing. Many manufacturers require an annual service in order to keep the warranty valid¹, and Which? puts the consequence bluntly: if a boiler is still under its manufacturer's warranty, not getting it serviced every year might invalidate its protection policy⁷. A household that lets servicing lapse can lose cover it already owns.

A service plan is bought separately, normally once the equipment is out of guarantee, and it bundles the annual service with repair cover. The trigger for a repair visit is either a breakdown or a fault found during the annual service itself. Worcester's plan, for example, covers repairs if an issue is found during the annual service or if the boiler stops working³.

The practical effect for a household's independence is limited but real. A service plan does not reduce reliance on gas or on the grid, and it does not make a home self-sustaining. What it does is transfer the risk of an unexpected repair bill to a fixed annual payment, and it keeps the servicing record that a warranty depends on. The dependence it creates is on a single provider: the plan ties the household to one company's engineer network and one company's terms, and the terms can change. Mixergy, for instance, reserves the right to increase the price of its plan at any time and to amend the terms and conditions at any stage, with customers notified of changes in advance⁶.

That is the trade. Predictable cost and a maintained service record, in exchange for a recurring payment and a contract that the provider can vary.

Who provides the plans: the maker or Domestic & General

The name on the plan is usually the manufacturer's. The company standing behind it usually is not.

Worcester's Maintenance & Support Plan is provided by Domestic & General Services Limited³. Vaillant's Maintenance and Support Plans are provided by Domestic & General Services Limited⁴, and the same company provides the Maintenance and Support Plans described on Vaillant's service pages⁸. EDF Energy sells boiler maintenance and insurance plans from Domestic & General⁵. The pattern is consistent across the market: a manufacturer or an energy supplier lends its brand, and a specialist administrator holds the contract.

This is not a criticism of the arrangement, but it is the thing to understand before signing. The engineer who attends may be drawn from the manufacturer's own network, as with Worcester's nationwide network of Gas Safe registered boiler engineers⁹, while the commercial terms, the exclusions and the claims process belong to the administrator.

There is a second category of provider: the energy supplier's own care plan. Cadent's safety guidance notes that if a household has an annual care plan with its supplier, the supplier will fix any problems with gas appliances and pipework¹⁰. That is a different product from a manufacturer plan, and it is usually tied to a supply relationship.

A third category is standalone boiler insurance, which may offer a broader range of cover, and some policies include an annual service¹¹. British Gas HomeCare Basic, for comparison, provides cover for a gas boiler and controls, including all repairs and, subject to certain terms, replacement of the boiler if necessary, plus accidental damage protection and an annual boiler service¹².

For a household weighing independence, the provider question is the one that decides how much control it retains. A plan administered by a third party can be repriced, retermed or withdrawn. A plan run by the maker of the equipment at least keeps the parts and the technical knowledge in the same organisation.

Worcester Maintenance & Support Plan: cover, limits and eligibility

Worcester's plan is the narrowest of the manufacturer plans on age, and the clearest on what it covers.

Eligibility turns on three conditions. The boiler must be under twelve years of age, it must be out of guarantee, and the household must not already have taken out a plan³. All three must hold. A Worcester boiler still inside its guarantee is not eligible, and neither is one that has passed its twelfth year.

Cover extends to the Worcester boiler and Worcester controls³. The plan provides an annual service each year³, and repairs are triggered if an issue is found during that service or if the boiler stops working³. Alongside the service, the plan includes ongoing hints and tips to keep the boiler in good working order³, and online support giving access to hints and tips and troubleshooting at any time⁹. Plan holders also get exclusive access to Domestic & General's Boiler Care portal³.

Support is delivered through a dedicated contact centre based in Worcester, open 7 days a week, 364 days a year⁹, and onsite visits are arranged using a nationwide network of Gas Safe registered boiler engineers⁹.

The twelve-year limit is tighter than the fifteen years that Which? reports as the usual maximum boiler age across cover policies generally¹³. A household with a Worcester boiler in its thirteenth or fourteenth year would fall outside the manufacturer plan while still being inside the age range many other policies accept.

What the plan does for independence is modest and specific. It keeps a Worcester boiler serviced by engineers working to Worcester's own instructions, which is the servicing record the warranty regime depends on, and it fixes the cost of repairs for as long as the boiler remains eligible. What it does not do is extend the equipment's life indefinitely or reduce the home's reliance on gas.

Vaillant Maintenance and Support Plan: cover, limits and eligibility

Vaillant's plans are the broadest of the manufacturer offerings, and they come with the most conditions attached.

Eligibility requires a domestic boiler under 15 years old that is in good working order and out of guarantee, and the boiler must not be protected by a similar plan⁴. Vaillant's own support article states the age rule more simply: a plan can be taken out for any boiler less than 15 years old⁶. The two formulations agree on the age limit and differ only in emphasis.

The waiting period is the feature households most often miss. The plan becomes effective 30 days after Vaillant receives the application⁴, and the same 30-day activation applies across Vaillant's plan documentation⁶. The plan itself runs for 12 months and starts the day it is taken out⁴. So a household that applies on the first of the month has a plan that has begun but does not yet respond to a claim.

Renewal reminders are sent 21 days before renewal⁴. The plan offers 12 months of protection for the heating system⁸.

Vaillant publishes three separate telephone numbers, and using the right one saves time. In-guarantee repairs are handled on 0330 100 3150, open Monday to Friday 8am to 6pm, Saturday 8am to 3pm and Sunday 8am to 12pm⁴. Technical queries about a boiler or central heating problem go to 0344 736 0049⁴. Service plan options are discussed on 0330 100 3143⁴. A second Vaillant number, 0330 102 8573, also appears in the manufacturer's material, and the two are not reconciled in the published pages.

The 30-day wait is the point at which a Vaillant plan differs most from a warranty. A household that buys the plan because the boiler has started making a noise will find the plan does not respond for a month. That is a deliberate design against adverse selection, and it is standard in this market, but it means the plan is a forward-looking product rather than a rescue.

Gold or Platinum: what each maintenance plan includes

Both Worcester and Vaillant tier their plans, and the tiers differ in one main respect: whether the heating system is covered alongside the boiler.

On the Vaillant side, the Platinum maintenance and support plan includes the boiler, controls, annual service and the heating system, including radiators and exposed pipes⁴. The Gold plan includes the boiler, controls and annual service, but not the heating system⁴. Vaillant's own summary describes the Gold plan as covering boiler controls and annual service⁸.

The service checks are the same across the two tiers. Vaillant states that its gold and platinum plans cover a set of checks including the flue and terminal, combustion air, all safety devices, gas pressure and heat input, operating pressure, external controls, the combustion fan, heat exchangers, gas and water seals, burners checked and cleaned, the ignition system, performance testing and a water quality check⁸.

EDF Energy's BoilerCare range follows the same logic under a different name. BoilerCare Gold looks after the boiler and the controls⁷, while BoilerCare Platinum looks after the boiler and controls plus the heating system⁷. Both tiers include repairs by Gas Safe engineers if the equipment stops working or fails the annual service⁷, and BoilerCare Platinum includes an annual service⁷.

The tier decision is really a question about what is likely to fail. A boiler and its controls are the parts a plan is designed around. Radiators and exposed pipework fail less often, but when they do the work is disruptive and the cost is not trivial. A household on a sealed system with older radiators is buying the Platinum tier for a reason; a household with a recently installed system is paying for cover it may never use.

Neither tier changes the home's relationship with its energy supply. Both are financial instruments against repair cost, and both keep the annual service in place, which is the part that protects the warranty.

Repair & Care Plan and Fixed Price Repair: when a one-off option fits

Not every household wants a subscription. Vaillant offers two alternatives for those who would rather pay once.

The Fixed Price Repair is a one-off package designed for broken boilers that are not within their manufacturer's guarantee⁴. It applies to any eligible Vaillant boiler unless it is uneconomical to repair⁴. All fixed price repairs include a gas safety check⁴. If the boiler cannot be repaired, the charge is limited to the fixed engineer time, at £99⁴.

The Repair & Care Plan is the subscription alternative, and its most distinctive term is what happens when a repair fails. If the engineer cannot fix the initial fault, or if the boiler is beyond economic repair, the household gets a full refund of any monies paid up under the plan⁴. The plan can be renewed annually⁶.

The exclusions on the Repair & Care Plan are stated plainly: scale, sludge and hidden pipework, repairs related to the installation of the boiler, cosmetic or malicious damage, and indirect costs such as gas supply⁴.

The gas safety check included with a fixed price repair is worth separating from the annual safety check that gas appliances require. Liquid Gas UK's safety guidance is that all gas appliances, including a gas boiler, gas cooker and gas fire, should be safety checked once a year and serviced regularly according to the manufacturer's instructions by a Gas Safe registered engineer¹⁴. A check that arrives with a repair is not a substitute for that annual routine.

For a household, the one-off route preserves independence in the sense that matters most here: no recurring payment, no contract that can be repriced, and no tie to a provider. The trade is that the household carries the risk of a second failure in the same year.

One-off Service: the 14-point check and what it costs

A one-off service is the simplest product in this market, and the one with the widest price spread.

Vaillant's one-off service includes a vigorous 14-point check on the boiler to maximise performance and ensure the boiler is safe⁴. Vaillant's annual servicing page describes a rigorous 12 point check on the boiler by an expert, in-house factory trained engineer⁸. The two figures come from the same manufacturer and are not reconciled in the published pages.

Independent pricing is more consistent. Which? reports that a one-off service should cost somewhere from £70 to £110 for a gas boiler⁷, and that the average is around £79⁷. The same source repeats the £70 to £110 range for independent boiler engineers⁷. Which? members reported a cost between £70 and £110, not including any resulting repairs¹³. Which? also reports that a boiler service will cost around £79 on average, though some can be up to £120 depending on where you are¹⁵.

Checkatrade's figure, cited by Uswitch, puts the average cost of a boiler service as of March 2026 at £100 including VAT¹⁶. Uswitch reports the average cost of a boiler service as varying from around £90 to £100¹⁶. A system boiler service takes about 1 hour¹⁶.

The spread between £79 and £100 is explained by what is counted. A headline service price often excludes any repair the engineer finds. Which? found the average cost people had paid for a one-off repair following a boiler service was £156⁷, and Uswitch reports that issues found during a service can lead to an additional bill averaging £120 to £750¹⁶. A full strip-down service, which includes removal of components to be cleaned, costs more than a standard service¹¹.

The case for servicing at all is not only about the warranty. The Association of Plumbing and Heating Contractors advises scheduling a professional service for a boiler or heating system, because regular maintenance improves efficiency, extends the lifespan of the system, and helps catch small issues before they become bigger ones¹⁷.

Mixergy Care Plan: cylinder cover with platform conditions

Mixergy's plan covers a hot water cylinder rather than a boiler, and its conditions are the most specific of any plan here.

The Mixergy Care Plan is a subscription option⁶. It can be taken out at any time within the first five years following installation of the cylinder⁶. The minimum initial subscription period is eighteen months⁶, and the same eighteen-month minimum applies to the Care Plan Plus¹⁸.

Cancellation is straightforward once that period has passed. A household can cancel at any time after the minimum subscription period has expired, the service persists for the remainder of the billing period, and the following payment is not withdrawn⁶. The same cancellation timing applies to Care Plan Plus¹⁸. Mixergy reserves the right to terminate the plan, and if it does, payments cease and any outstanding cover period is reimbursed⁶. If the household does not comply with its responsibilities, Mixergy reserves the right to terminate the plan and payments cease⁶.

The conditions are where this plan differs from a boiler plan. The cylinder must be connected to the Mixergy platform for at least 300 days per year⁶, and it must not be unconnected for any consecutive period of 28 days or more⁶. Payments must be kept up to date⁶. Mixergy reserves the right to increase the price at any time, to reflect changes in business costs and/or inflation, and to amend the terms and conditions at any stage, with customers notified in advance⁶.

The warranty link is the reason the plan exists. The Mixergy cylinder warranty requires annual servicing, evidenced either by a benchmark service record filled in after each annual service by the installer, or by subscribing to the Mixergy Care Plan or Care Plan Plus with the unit connected to the online analytics platform and monitored each year since purchase¹⁹. Subscribing to the plan and complying with its responsibilities maintains the cylinder's warranty without submitting annual service documentation⁶.

Care Plan Plus extends further. It covers the pump assembly among the Mixergy supplied peripheral componentry¹⁸, and the installation work to replace a peripheral component is covered for as long as the subscription is maintained, up to a period of 25 years from installation¹⁸. The safety valve is checked on an annual basis by a qualified professional following the guidance in Mixergy's installation and servicing guides¹⁸. All of the household's responsibilities under the Mixergy warranty and the Care Plan must be complied with¹⁸.

The independence question is sharper here than with a boiler plan. The Mixergy plan requires the cylinder to be connected to the manufacturer's platform for most of the year. That is a cloud dependency written into the contract, and it is the condition that keeps the warranty alive. A household that wants the warranty without the platform has one alternative: the benchmark service record, completed by an installer after each annual service¹⁹.

Eligibility, waiting periods and the age limits that decide if you can join

Age limits are the first filter, and they vary more than the marketing suggests.

Worcester draws the line at twelve years³. Vaillant draws it at 15 years⁴. Which? reports that some cover policies set maximum ages for boilers they will allow cover for, usually 15 years¹³. The general eligibility wording used across maintenance and support plans is that the heating equipment should be owned by the householder, be in good working order and under 15 years of age when the plan starts⁷.

Ownership and condition matter as much as age. The equipment must be owned by the householder and in good working order⁷. A boiler that is already failing will not pass the condition test, and a rented property's boiler will not pass the ownership test.

Waiting periods are the second filter. Vaillant's plan becomes effective 30 days after the application is received⁴. That is the longest stated wait among the plans here. Worcester's plan does not publish a comparable waiting period in the material reviewed.

The age limits interact with the wider policy landscape in a way that matters for households in the devolved nations. In Northern Ireland, the Northern Ireland Sustainable Energy Programme notes that households with an existing oil or gas boiler over 15 years old might be eligible for whole house solution schemes²⁰. The Affordable Warmth Scheme applies where a boiler is at least 15 years old, and requires the householder to be over 65, or to have a child in receipt of Child Benefit or Kinship payments, or to receive Disability Living Allowance, Personal Independence Payment, Attendance Allowance or Industrial Injuries Benefit²¹. Those are grant schemes rather than service plans, but they use the same fifteen-year threshold, and a household at that boundary is choosing between paying for cover on an old boiler and replacing it.

The Boiler Upgrade Scheme sits alongside these. Citizens Advice notes that an expanded Boiler Upgrade Scheme and the promise of new grants for low-income households could bring energy home upgrades within reach²². Ofgem operates a weekly payment schedule to installers under the scheme²³, publishes monthly operational updates²⁴, gives at least two days' notice of site audits²⁵, and notifies installers within 14 days of deciding to withhold a payment and within 21 days of concluding a review²³. Retrofit cost figures published by the Energy Saving Trust do not include potential discounts from funding, for example the Boiler Upgrade Scheme²⁶.

For a household deciding whether to join a plan or replace the equipment, the age limit is the decision point. Below twelve years, Worcester is available. Below 15, Vaillant is. Above 15, the plan market largely closes and the grant and replacement routes open.

What plans exclude: installation costs, scale, sludge and repair value caps

Exclusions are where service plans earn their margin, and they are stated more clearly by some providers than others.

Vaillant's Repair & Care Plan lists its main exclusions directly: scale, sludge and hidden pipework, repairs related to the installation of the boiler, cosmetic or malicious damage, and indirect costs such as gas supply⁴. Each of these is a common cause of boiler failure. Scale and sludge are the products of an untreated system, and hidden pipework is by definition not visible at the point of sale.

The Mixergy warranty exclusions run along similar lines. The warranty is invalidated if the cylinder has been misused, tampered with, or subjected to neglect¹⁹, if it has been modified in any way other than by Mixergy¹⁹, or if it has been subject to frost damage¹⁹. Frost damage is a particular risk for a cylinder in an unheated outbuilding or loft.

Installation costs are excluded across the board. The Energy Saving Trust's retrofit cost figures do not include potential discounts from funding, for example the Boiler Upgrade Scheme²⁶, and the same principle applies to plan cover: a plan maintains equipment, it does not pay for its replacement or for the work of installing a new one.

There is a statutory backdrop to installation spending that is worth knowing. The legislation covering the compulsory scheme electricity supplier obligation states that spending on the installation of boilers or central heating systems must not, in total, exceed the supplier's obligation percentage of £800,000²⁸. That is a cap on supplier obligation spending, not a household cost, but it shows how tightly boiler installation support is bounded in law.

The Boiler Upgrade Scheme's Product Eligibility List carries its own caveats: it indicates products meeting MCS standards, does not guarantee installation eligibility, does not consider SCOP, and is not exhaustive²⁹. A household reading a product listing as a promise of a grant would be reading it wrongly.

The pattern across all these exclusions is consistent. Plans cover the failure of the equipment they name, in the condition it was in when the plan started. They do not cover the consequences of a system that was already deteriorating, the cost of installing replacement equipment, or damage caused by neglect or frost. For a household, the exclusions are the part of the contract that determines whether the plan pays out, and they are worth reading before the first payment rather than after the first claim.