Remove air lock from storage tank on gravity feed open vent

[markymarkuk]

Hi Guys
Had to drain my Potterton Open Vent, Gravity fed system via the lowest radiator so I could replace a pump by my boiler downstairs. Refilled and bled rads. Every radiator is nice and hot, however the two pipes that go in the side of my NEW copper hot water tank in Airiing cupboard are both stone cold. So I'm guessing an air lock. How best to try and sort this problem, any help appreciated.

I've attached a diagram of my system (its from the 70s).

Untitled

• markymarkuk
• 10 Sep 2013
• 2

 

[Gasguru]

It's an old system so is the cylinder coil heated by gravity circulation...have you used a cylinder designed for modern pumped circulation? Gravity circulation was obsolete 40 years ago.