Primatic system

[tim32]

Hi I have with the help of my very good friend, changed our primatic cylinder to a standard indirect system, complete with f&e tank, however I am still finding that the upstairs rads are aproximatly two thirds full of air, and refuse to clear. The downstairs ones are no problem and work fine, one possible clue could be that when we try to bleed them the vent into the f&e tank returns some water.
any ideas would be appreciated
many thanks
Tim n(vgf) Jane

[tim32]

Hi we have just got rid of the air, by means of putting a hose pipe onto the boiler drain and purging, this worked for a time, a very short time unfortunatly,
We found that as the heating system warmed up the water expanded and some left the system by means of the overflow, in the f&e tank.
When the system got switched off, cooled, and turned on again the water which had expanded and run off, was not replaced, and we have as much if not more air in the system.
The f&e tank is fairly low down, the bottom will be about the same height as the top of the upstairs rads, could it be that there is not enough pressure in the system to fill the rads, and if not is there anything that can be fitted to the system to sort it?
ta
Tim n Jane

[mark6266]

your f&e tank should be a least 1 meter above the highest point in the system
regards mark (allinplumbing@fsmail.net)