A boiler replacement is a planned job, not a mystery. The exact time depends on the house, but the stages are consistent.
1. Look at the system, not just the boiler
Before anything is ordered we need to know the current system type, flue position, how hot water is produced, and whether the pipework and radiators are staying. A combination boiler going onto an existing combi circuit is a different job from changing how the house makes hot water.
That is why boiler installation and central heating installation are separate pages.
2. Agree the work
The visit should produce a clear description of what is being replaced, what is staying, and any extra work — controls, a flue change, or pipework that has to move. We do not publish prices or durations as promises because they depend on that description.
3. Isolate and remove the old appliance
The existing boiler is isolated, disconnected and taken out. This is regulated gas work. It is not a DIY stage.
4. Fit the new boiler
The new appliance is hung or sited, connected to the heating and water services, and given a suitable flue and condensate route. Controls are connected so the system can be used properly.
5. Commission
A new gas boiler has to be commissioned. That is the point at which it is set up to run on the system it has been fitted to. Until that is done, the job is not finished.
How long it takes
A straightforward like-for-like replacement is often a day’s work. Anything involving a change of system type, a difficult flue or extra pipework takes longer. We confirm that after seeing the property, not before.
If you are still deciding whether you need this job at all, start with repair or replace.