coil leak in cylinder

[DiyAngel]

We are having to top up 1/2 bar every 12 hours. I think that our cylinder may have a coil leak.

As we have no evidence of water anywhere else. The motorised valve doesn't appear to ever be off so calls for hot water constantly- this valve has been replaced recently. But still appears to be in the open position its a BG MVSP9-valve actuator(blue)

To prove my suspicion of a coil leak. Can I manually close the valve so that the heating still works and just goes round the bypass radiator.I assume doing this will prove one way or another if there is a coil leak.

If I can't physically shut the valve, If I turn the electric off to it will it stop in the open or shut position? Or is there a simpler way of proving a coil leak.

The hot water tap this supplies, the water hasn't changed colour but it does smell different as in metallic. (PRV and expansion vessel been checked ) Thanks

 

[corgiman]

What cylinder have you got, make and model

and what boiler have you got?

 

[superdupergasman]

Get BG out seeing as you have one of their valves.

Could be under the floor your leak, or the heat exchanger of the boiler, to name 2 places.

 

[gasandoilman]

i had one recently the way i found it was the tank was filling in the loft the drop was a bit faster than yours but you could see it backing into the cold storage tank

 

[Goldspoon]

very hard to read without punctuation it all becomes confused punctuation assists the flow it was designed to help understanding is made easier do you agree