Boiler Servicing in Mitcham, London

Once a year is the standard advice, and it is what most manufacturers' warranties ask for. The best time is late summer or early autumn, before the heating season, so any part that needs replacing can be ordered without the pressure of a cold snap. A boiler that has been running trouble-free for years still wears quietly inside, and the service is how scale and sludge get found early.

Published 2026 London guides show a standard annual service at about £80 to £130, with inhibitor treatment at £90 to £150 and a magnetic filter fitted for roughly £90 to £150. Combined packages of a service with a power flush run higher, about £250 to £500. The partner company gives a written quote, and any parts that the service reveals are quoted separately before they are fitted.

The engineer inspects the casing, burner and ignition, checks the heat exchanger for scale and cracks, examines the flue and clears the condensate trap on a condensing boiler. They test the pressure, expansion vessel and safety devices, take a flue gas reading and check the controls. Finally they refit the casing, test the boiler under load and note anything that needs future attention.

Yes. Thames Water's 2024 report for the Mitcham supply area gives hardness of 262 mg/l as calcium carbonate, which is hard. That scale builds up on the hottest surfaces inside a combi and in the heating circuit, so a service is where the engineer can see it, recommend a magnetic filter or inhibitor and flag any exchanger that is close to failure. It will not stop scale completely, but it slows it.

Yes, because most boiler faults develop quietly. A blocked condensate pipe, a weak pump or a drifting gas reading can show no symptom until the boiler locks out. A service is also the paper trail many warranties ask for, and it is the engineer's chance to check the flue, an area where a fault can be dangerous without being obvious. Ask us to book one in the quieter months.

They are different jobs that are often done in the same visit. A service follows the boiler manufacturer's instructions and maintains the appliance; the landlord's annual gas safety check is a separate legal duty that covers every gas appliance and flue in the let property and produces a record for the tenant. Tell us you are a landlord when you book so the partner can arrange both and agree access.

A service is not a repair, but it is often where a fault is found. If the engineer finds a worn part, they will tell you what it is, what it costs and whether the boiler is still worth repairing. Anything beyond the service is quoted separately in writing before it is done. If the boiler has already failed, go to our emergency boiler repair page instead.

On a hard-water supply and an older heating circuit, a magnetic filter is a sensible low-cost addition. It catches magnetite sludge before it reaches the boiler's heat exchanger and pump, and it can be cleaned at each service. Guide prices for fitting run roughly £90 to £150 in London. If the system is already badly sludged, a cleanse comes first, which our power flushing page covers.

A typical domestic service takes between 45 minutes and an hour and a half, depending on the boiler, its access and what the engineer finds. Boilers in cupboards or lofts take longer, and a boiler with scale or a blocked condensate pipe takes longer again. The partner will tell you when they arrive and will not rush a safety check to hit a time.

An independently owned partner company sends an engineer to do the service. We text you their name before they arrive, and they quote and invoice you directly, which means we handle no payment. If anything is not right afterwards, ring 07897 016796 and we chase it with the partner. See who does the work for the full explanation.