Replace the boiler in a let property when repair can no longer keep heating and hot water in proper working order: the appliance has been classed unsafe and cannot be put right, parts for the model are in doubt, or breakdowns keep repeating through the heating season. Repair it again when an engineer can name the part that failed, that part is still available, and the service history is complete. No regulation in England sets a maximum age for a boiler in a rented home, so condition, safety and parts supply decide, not the year on the data plate.
Repairing the boiler again or replacing it: what differs for a landlord
Both routes have to end the same way: heating and hot water working safely in the let property. What differs is the duties each route triggers, the parts supply behind it and the paperwork that lands in your file.
| Criterion | Repairing the existing boiler | Replacing the boiler |
|---|---|---|
| Section 11 duty, England and Wales | A successful repair returns heating and hot water to proper working order under section 11, Landlord and Tenant Act 1985. | The route when repeated repairs no longer keep heating and hot water in proper working order. |
| Spare parts for the model | Depends on parts still being stocked for that model, which the engineer checks before quoting. | Puts a current model in the property, so parts supply stops being the limiting factor. |
| Rules triggered by the work | Nothing is newly installed, so the Boiler Plus requirements in England do not apply. | Boiler Plus applies in England: 92 per cent minimum ErP efficiency, time and temperature control, plus one extra measure for a combi. |
| Annual duties that follow | Annual gas safety check and maintenance by a Gas Safe registered engineer carry on unchanged. | Same annual duties, with the first gas safety check due within 12 months of installation. |
| Work inside the tenant's home | Work is limited to the failed component, so less time is spent in the property. | The old boiler is removed and taken away, and the manufacturer warranty is registered for you. |
Neither column is automatically the landlord's answer. A boiler with a full service history and one failed part is a repair job. A boiler that cannot be made safe, or whose parts have run out, has stopped being one.
When repairing the boiler again is the right call in a let property
Repairing the boiler again fits when an engineer can name the component that failed and that component is still available. A fault code, a part and a fix describe a repair. A pattern of unrelated failures does not.
- The boiler is still inside its manufacturer warranty. Vaillant requires an annual service by a Gas Safe registered engineer, recorded in the Benchmark logbook, to keep the guarantee alive. Baxi asks for registration within 30 days of installation, a completed Benchmark checklist and annual servicing, and shortens the warranty if those are missing.
- The service history is complete and this is the first fault of the season. One failure on a maintained appliance is a repair, not a verdict on the boiler.
- The fault sits in the system, not the appliance. Repeated pressure loss after topping up points at the system. Vaillant and Ideal Heating both treat that as a case for a Gas Safe registered engineer to investigate.
- A defect on the gas safety record can be put right. HSE expects defects to be remedied without delay, and the remedial action is recorded on the gas safety record.
Mid-tenancy, a clean repair also avoids a second round of access arrangements with the tenant. Our longer guide on repair or replace for an ageing boiler sets out the same question for an owner-occupied home.
When replacing the boiler is the right call in a let property
Replacing the boiler becomes the right call once repair stops keeping the property safe and warm. Four situations point that way, and none of them is about age on its own.
- The appliance is unsafe and cannot be put right. Where there is reason to suspect a gas appliance is unsafe, HSE states it must not be used until the defect has been corrected.
- Parts for the model are in doubt. Worcester Bosch holds spare parts for at least 10 years after a model leaves production. Ask the engineer to check availability for your exact model rather than guess from the install date.
- Breakdowns keep repeating through the heating season. The HHSRS landlord guide for England names poor or inefficient heating systems among the causes of the Excess Cold hazard. Around 21°C is given as a healthy indoor temperature, and below 16°C there are serious risks for older occupants.
- Other works are already planned. The government response on the energy performance of privately rented homes sets 1 October 2030 as the compliance date for the raised standard, with a dual metric: fabric first, then a choice between a heating system standard and a smart readiness standard.
HHSRS guidance for England expects a landlord to provide heating that is adequate, safely installed and maintained, and controllable by the occupier. A boiler that leaves the property cold every few weeks is not meeting that description, however many times it is repaired.
Does the law in England say when a landlord must replace a boiler?
No law in England sets a maximum age or a replacement date for a boiler in a rented home. Three duties decide instead, and they work together.
- Gas Safety (Installation and Use) Regulations 1998, as amended: you must have the gas appliances, pipework and flues you provide maintained by a Gas Safe registered engineer, and a gas safety check carried out every 12 months.
- Section 11, Landlord and Tenant Act 1985 (England and Wales): installations for space heating and heating water must be kept in repair and proper working order. The standard allows for the age, character and prospective life of the property.
- HHSRS, England: a poor or inefficient heating system can contribute to the Excess Cold hazard, which a local authority assesses in the property.
Condition decides, not age. A boiler is acceptable in a let property for as long as it is safe, maintained and keeping heating and hot water in proper working order. Once repeated breakdowns stop doing that, replacement is how you meet section 11, not an optional upgrade. The wider duties are set out in our guide to landlord gas safety in England.
Two separate strands run every year, and HSE warns against assuming one covers the other. The annual gas safety check is a safety check. Maintenance follows the manufacturer's instructions, or yearly where no instructions exist, unless a Gas Safe registered engineer advises otherwise.
What a replacement boiler adds to a landlord's duties in England
A replacement gas boiler in an existing home in England has to meet Boiler Plus, in force since 6 April 2018. The minimum ErP efficiency is 92 per cent, and time and temperature control must be present and working. A combi replacement needs one further measure: weather compensation, load compensation, flue gas heat recovery, or a smart control with automation and optimisation. System and heat only boilers do not need that extra measure, and Part L differs in Wales and Scotland.
Three more duties follow the new appliance into the property. The first gas safety check falls within 12 months of installation, then every 12 months. Manufacturer warranties stay valid only with an annual service by a Gas Safe registered engineer, and Baxi also requires the magnetic filter to remain fitted and serviced for the warranty period.
If the replacement moves the boiler to a different room, check the alarm position again. Since 1 October 2022 in England, a carbon monoxide alarm is required in every room used as living accommodation that contains a fixed combustion appliance, gas cookers excepted. Our guide to carbon monoxide alarm rules for rented homes in England covers the detail.
What you or your tenant may check on the boiler before calling an engineer
Four checks are safe for a landlord or tenant to make on a boiler, and no more. They sometimes explain a call-out that looked like another breakdown.
- The pressure gauge. Manufacturers give roughly 1 to 1.5 bar on a cold system as the normal range.
- Thermostat and programmer settings. A changed schedule or a flat battery in a wireless thermostat can look like a dead boiler.
- The reset button, used as the manufacturer's instructions describe.
- Bleeding radiators. Open the vent valve at the top of the radiator slowly, close it as soon as water appears, then look at the pressure again.
Everything else is work for a Gas Safe registered engineer. That covers the gas supply, the flue, seals, the condensate route inside the appliance and anything behind the casing. If pressure drops again after topping up, that is a system fault to report, not a check to repeat.
Repair or replace: the landlord's decision in one paragraph
Repair the boiler again if the engineer can name the failed part, that part is available, the service history is complete and no defect on the gas safety record is left open. Replace the boiler if the appliance has been classed unsafe and cannot be put right, if parts for the model are in doubt, or if breakdowns keep leaving the tenant without heating through the season.
Where the decision is close, ask the engineer two questions in writing: are parts available for this model, and what caused this failure. A free survey and a written fixed price before any work starts give you both answers on paper for the property file.
If the annual check is due on the same property, you can arrange the landlord gas safety certificate (CP12) for the same visit.
Sources
- HSE — Maintenance: gas appliances and flues
- HSE — Gas safety checks: who needs them?
- HSE — Gas safety checks: what if…?
- Landlord and Tenant Act 1985, section 11
- GOV.UK — Landlord and agent guide to the HHSRS
- GOV.UK — Improving the energy performance of privately rented homes: 2025 update
- The Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022
- Worcester Bosch — Boiler Plus legislation
- Worcester Bosch — Spare parts
- Baxi — Boiler warranty information
- Vaillant — Domestic boiler guarantee terms and conditions
- Ofgem — ECO FAQs for domestic consumers and landlords