Boiler·25 Jun 2026 · 3 min read
By Mohammed Miah, Gas Safe registered heating engineer
Most straightforward combi-to-combi boiler replacements can be completed in one working day, with the same boiler type going back in roughly the same spot.
What makes an installation take longer
- Moving the boiler to a different location
- Changing the boiler type (for example, system to combi)
- Converting the heating system
- Installing new pipework or a new flue run
- A system flush as part of the same visit
- Installing a complete heating system where none currently exists
Jobs involving any of the above can typically take two to three days. A full new heating system installation, pipework, radiators and boiler from scratch, can take around a week. We'll always give you a realistic timeframe upfront once we know exactly what's involved, usually confirmed after a free estimate or site survey.
