leak from manifold

[john cushnie]

We have a Grant oil fuelled boiler running our under floor heating, I've noticed that 1 towel rail of 2 is losing its heat and I'm having to re-pressurise it within a few days. I have since noticed that there is a leak from the under floor heating manifold, see the image, I thought the 2 heating systems were separate, do you think this is the problem causing the pressure drop?

 

[ianmcd]

separate systems but share the same primary water, so a leak anywhere will cause the system pressure to drop

 

[john cushnie]

In some ways that's good news as it probably the problem, looking at the image can that small part be replaced?