Hi all,

I have a intergas boiler with a developing limescale problem on the domestic hot water side. Taking the heat exchanger out looks to be impractical, so I thought I'd try the alternative technique of circulating descaler through it in situ by connecting up a pump and a bucket of DS3 descaler to the nearby hot and cold washing-machine valves.

I can easily pump cold water through the heat exchanger this way, but as soon as I introduced hot water (by pouring it into the bucket) the pump gave up. To be fair it was the cheapest drill-attached pump I could find:
https://www.amazon.co.uk/Wolfcraft-2.../dp/B0001P1972

Any suggestions for a pump which is up to pumping hot acidic water?

Cheers!

Martin