What drives the price
The biggest factor is the number of radiators — more radiators means more time. System size, how badly sludged it is, and awkward access or old pipework all add to the job as well.
Weighing it up
Against the cost, set what sludge is costing you: higher bills from poor efficiency, repeat breakdowns, and the risk of an expensive boiler repair if the heat exchanger blocks. On an otherwise sound system, a flush often pays back.
When it’s worth it
A flush makes most sense when there’s genuine sludge and the boiler is worth keeping — especially before fitting a new boiler, where many manufacturers require a clean system to honour the warranty.
When it isn’t
If the system’s only lightly affected, a cheaper chemical flush may be enough; if the boiler is old and failing anyway, spending on a flush can be throwing good money after bad. We’ll tell you honestly which camp you’re in.
Want a straight answer on whether a power flush is worth it for your system? We’ll assess it and quote honestly — no flush sold that you don’t need. South Manchester and Cheshire.
See our power flushing service
