Rads in the upstairs from rooms not heating

twilo

Hi there,
In our 3bed semi the rads in the two front rooms upstairs are only heating up sometimes. It is zoned heating in where the downstairs rads are fine. I have bled the rads and no air comes out, turn on the heating and nothing happens. Sometimes if i turn on the upstairs heating only, they will heat up. We had a leak in the downstairs hallway a few months back, this has been fixed but have had issues with the upstairs rads ever since. Plumber reckons we may need a new pump as it might not be powerful enough, the house is only 3 yrs old. Also when i turn on the water (zone 3) i can hear the pipes gurgling suggesting air in that system. Could air in the water zone be causing the rads on the upstairs zone (zone 2) to not heat up properly. Any suggestions greatly appreciated.
Mike.

neeb

Do any upstairs rads heat? Do you have trvs?

If it had been like that from the start it would more likely be a under sized pump, as this is a new fault then it's more likely that air is an issue, it is to much of a coincident that the fault occurred after you lost water from your system, if the system is tank fed it can be harder to push the air out and this can cause a resistance around a circuit, but if your system is mains fed then it less likely to be air as the mains pressure pushes out the air easier(if it's strong enough), also if you have a balancing valve(wheel head valve) on your cylinder flow and return pipework and it's left fully open it can rob heat from the upstairs circuit, i would say it's a air issue as and if you have a tank fed system i would consider converting to a mains fed system if it's practical to do so, Gary