Advice & guides

Power Flushing Guides

Straightforward answers to the questions homeowners ask us most about power flushing, sludge, cold radiators and protecting their heating system.

Understanding power flushing

A plain-English explanation of what a power flush is, what it does and why it’s done.

How to tell whether your heating actually needs a power flush — and when it doesn’t.

Eight warning signs of sludge in your heating system, and what else might cause them.

A step-by-step walkthrough of what actually happens during a power flush.

Typical timings for a power flush, and what makes one take longer.

How a power flush compares with a chemical flush, and when each makes sense.

The honest answer on whether a power flush can harm a boiler.

Why old radiators sometimes leak after a flush, and how to spot the risk in advance.

Whether older pipework and microbore systems can be safely power flushed.

Magnetite, rust, limescale and more — what comes out of a system during a flush.

The difference between a power flush and a mains-pressure system flush.

If you’re dealing with a specific issue, start here.

Cold at the bottom, cold at the top, one radiator or a whole floor.

Black water, sludge and dirty heating water explained.

Why systems are cleaned before a new boiler is fitted.

Tell us about your heating and we’ll come back to you with honest advice and a clear quote. No obligation.