Treat an older boiler as a due-diligence item, not an automatic replacement bill. Identify the system, request records, understand what the survey did not test, and budget for uncertainty before exchange or completion.

Documents to request

• installation invoice and commissioning record;
• Building Regulations or other applicable compliance certificate;
• guarantee registration and terms;
• service history and recent repair invoices;
• landlord gas-safety records if the property was rented;
• manuals for boiler, controls and cylinder;
• oil-tank records for an oil system; and
• alterations to flue, chimney or protected fabric.

Missing paperwork does not diagnose the boiler, but it changes what can be verified.

What a general survey may not cover

A visual home survey is not normally a strip-down service, combustion test or performance guarantee. Read its scope and exclusions. If heating condition affects the purchase, arrange a specialist inspection with access and seller permission.

Questions during viewing

Record make/model, system type, apparent age, controls, cylinder/tanks, visible pressure, flue, leaks/corrosion, radiator condition and whether all rooms receive heat. Do not remove covers or operate unfamiliar controls without permission.

Budget scenarios

Create three allowances: no immediate work, service/minor repair, and surveyed replacement. Do not insert an online average as a certainty. Include access, controls and system condition, especially in older properties.

Frequently asked questions

Does a general home survey test the boiler fully?

Usually not. Check the survey level and wording. A specialist heating inspection has a different scope.

Which documents should I request?

Installation/compliance, commissioning, service, repairs, guarantee, manuals and any fuel-storage or protected-building records.

Suggested on-page component

Use a Homebuyer Heating Evidence Checklist that records present/missing documents and inspection questions without estimating condition.

Related guides

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