The circulation pump in the expansion tank of my Alde heating system has become very noisy. Do I need a replacement?

A noisy pump is usually a result of the bearings wearing out. This can be caused by normal wear and tear or, in some cases, contamination of the fluid in the heating system. The pump bearings are replaceable and it is advisable to remove the pump and send it in for service/repair. If the fluid in the system is found to be contaminated with sediment, evident from being discoloured either to black or brown, then as well as having the pump reconditioned, it is advisable to drain the heating system, flush it thoroughly and refill it with a 40% antifreeze solution.

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