I can hear a kind of continuous humming sound coming from the underfloor heating in the flat above me. What is causing this and can anything be done about it.

How do you know it's the underfloor heating?
I think it is a wet system.Is it a wet (boiler), or an electric under floor system, do you know?
I really hope it isn't the underfloor heating.How do you know it's the underfloor heating?
That's a good idea. They are away at the moment.+1.
Have you confirmed this by asking them to switch it off to test?
If it is the underfloor heating, I guess I will have to buy the apartment from them.If it's a wet type, I expect there's a pump on the manifold; they tend to makes the pipes hum, and the way the manifold is screwed to the wall can also contribute to vibration noise. Not sure I rate your chances of getting the upstairs neighbour to do anything about it though, unless it's happening because the pump is getting knackered :/
I think it is a wet system.
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