Recent content by paul09

I've checked the expansion tank line and it seems to be ok. Hot water is moving up it as the water heats up and expands. There is plenty of water in the expansion tank. The noise is particularly noticeable when the pump shuts off.

I have a standard pumped system with a 3-way valve in the airing cupboard at the top of the house. The system runs normally, providing normal hot water and heating. When the 3-way valve operates, however, there is a surging/swirling noise like a sudden flow of water, or like a bottle being...