Boiler Repair Cost & How Long a New Install Actually Takes

Two questions come up constantly when a boiler starts playing up: what will a repair actually cost, and if it needs replacing instead, how long will I actually be without heating? Here are straight answers to both.

Boiler repair costs

These are realistic ranges including parts and labour for a straightforward, single-fault repair. The exact cost depends on the specific part needed and how accessible the boiler is — we always diagnose the fault first and confirm a fixed price before starting any work, rather than charging by the hour with an open-ended total.

How long a repair actually takes

Most repairs are sorted in a single visit — typically 1-3 hours once the fault is diagnosed. The exception is when a specific part isn’t something we carry on the van and needs ordering; in that case we’ll tell you honestly at the diagnosis stage and book a follow-up visit as soon as it arrives, rather than leaving you guessing.

When repair stops making sense

If your boiler is older and has needed more than one repair recently, it’s worth reading our guide on signs your boiler needs replacing — sometimes what looks like “just another repair” is actually the start of a pattern that makes replacement the more sensible spend.

How long a new boiler installation takes

If replacement is the right call, here’s what to expect for timing:

• Like-for-like combi swap (same type, same location): 1 working day
• Combi relocated to a new spot, or output upgraded: 2 days
• Switching to a system boiler with a cylinder: 2-3 days

These assume reasonably accessible pipework — older or unusual systems can add time. We’ll confirm exact timing at the survey stage, before you commit to anything.

Will you be without heating during the install?

Yes, for the duration of the work — there’s no way around disconnecting the old boiler before the new one goes in. If you’re planning ahead (rather than dealing with an emergency), booking installation in late summer or early autumn avoids doing it during the coldest weeks. If it’s a genuine emergency replacement in winter, we can talk through temporary heating options to bridge the gap.

What can extend either job beyond the estimate

For repairs, a fault that initially looks straightforward sometimes reveals a second underlying issue once the first is fixed (a common example: a pump replacement uncovering sludge build-up that also needs a power flush to properly resolve). For installations, older or non-standard pipework, awkward access to the boiler’s current location, or asbestos-era materials in very old properties can all add time. We flag anything like this as soon as we see it, with a clear cost before proceeding — never as a surprise on the invoice.

Getting a fixed price for either

Whether it’s a repair or a full replacement, we always survey or diagnose first and give you a clear, fixed price before starting — never an open-ended hourly rate. See our full new boiler cost guide for installation pricing, or get in touch and we’ll take a look at what’s actually needed.