Anyone recognise this?

[Bob52]

Hi, I have an old and quite long house with a gravity fed system. This item pictured I think is a pump or valve, it’s attached to the 22mm cold feed from attic tank to hot cylinder below. It is wired up to a 3 pin plug and on a timer! It’s not actually plugged in but when I do it just continuously runs? Does anyone know what it’s meant to be doing?

 

[TimboTwo]

Are you sure that's on the cold feed? It looks like a secondary hot water circulating pump. A clearer photo would help.

 

[EvilDrPorkChop]

Looks like a circulating return pump to me.

 

[Clear Plumbing]

EvilDrPorkChop is bang on, circulation pump for a secondary return, it means you get hot water to your taps instantly when switched on, well at least you should if installed correctly

 

[exedon2]

I would agree thats a circulating pump difficulty to tell from pic but is it yellow painted?
If so could be a bronze pump though if it is on tank feed difficult to know why!

 

[snowhead]

It would make dense for a Long House to have secondary circulation.
The return pipe must be Tee'd into the feed from CWS tank just above the pump.

 

[Bob52]

Thanks for reply’s everyone, you are correct it’s the hot feed not cold. And yes a circulating pump would make sense as the house is quite long! Thanks again.