How long does a boiler installation take?
How long fitting a new boiler really takes, from a simple swap to a full conversion, and what happens on the day.
One of the first questions people ask is how long they will be without heating. The good news is that most boiler installations are quicker than you might think.
Typical installation times
- Like-for-like combi swap: usually one day, often four to six hours
- System or regular boiler swap: around one day
- Converting to a combi (removing tanks): two to three days
- Moving the boiler to a new location: one to two days depending on the pipework
A straightforward swap, where the new boiler goes in the same place as the old one, is the fastest. Bigger changes take longer because of the extra pipework and removal work involved.
What happens on the day
- Arrival and prep. Your engineer protects the work area and isolates the gas, water and electrics.
- Removal. The old boiler, and any tanks or cylinder being replaced, are drained and removed.
- Fitting. The new boiler is fitted, connected and, where included, a system filter is added.
- Flush and fill. The system is cleaned or flushed to remove debris, then refilled and pressurised.
- Testing and handover. The engineer tests everything, checks for leaks, sets your controls and talks you through the new boiler.
- Certificate and warranty. You get your Gas Safe certificate and the warranty is registered.
What can affect the timescale
The age and condition of your existing pipework, whether the boiler is moving, and any extras like a new flue or thermostat can all add time. A good engineer will tell you the expected timescale before work starts, so there are no surprises.
Get a clear plan
When you get a fixed price from Norvera, we assess the job properly and tell you how long it will take. Answer a few quick questions to get started.
Frequently asked questions
Can a boiler be fitted in one day?+
Yes. A straightforward like-for-like combi swap is usually completed in a single day, often within four to six hours. More complex jobs, like moving the boiler or changing type, can take two to three days.
How long does it take to convert to a combi?+
Converting from a regular or system boiler to a combi typically takes two to three days, because the old tank and cylinder are removed and the pipework is reworked. Your engineer will confirm the timescale before starting.
Will I be without heating for long?+
For most swaps you are without heating and hot water only for the working day, and back up and running by the evening. For longer jobs the engineer will keep disruption to a minimum and explain what to expect.
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