water coming from vent pipe when heating is turned on help

[jmcni]

Hi i have went to a job where when the heating is turned on the water immediately comes out of the vent into the feed and expsion tank in the roofspace how do i discover what is causing this to happen is there a checklist as such eg pump speed , temperature , blockage and so on i found out as the overflow from the f & e tank was leaking and wonder what i shold do

 

[Billy Bob Bob]

pump speed and condition,gas pressures (over gassing) system problems ,corrosion or design

 

[jmcni]

its an oil fired system they had some oil pipe replaced that had frozen in december so what course of action would you recommend

 

[Gray0689]

I'd check the header tank valve might be slightly passing then when heating goes on expansion rising water line worth a go if system been working fine
Might even be vent has dropped in to water level
The new oil line would be nothing to do with it

 

[Billy Bob Bob]

check pump speed and system design dont know anything about oil some of the other members might be able to give a better answer regarding oil

 

[Bartdude]

The fact that it's an oil boiler shouldn't make any difference.Have a look at this thread.It's not identical to your problem but there's some good info in there.

http://www.ukplumbersforums.co.uk/c...-discharging-loft-vent-pipe-ch-turns-off.html

 

[jmcni]

Thats all great guys does anyone think it may just be a pump needing changed or thermostat i think a lot of he ideas are extreme in the link bartdude athlough thanks for bringin it to my attention it did help just th more i think about it the more i think the systems overheating or over pumping let me know what yous think please

 

[Gray0689]

When you put heating on chech header see if water coming from vent pipe

 

[jmcni]

yes gray it is

 

[Gray0689]

Try turning pump to speed 2 see if that helps

 

[Ian10261]

Dont you just love problems on open vent systems? I take the view that the system was probably working ok at one time and if nothings been messed with and all the rads get hot enough then its more than likely to be a blockage or restriction somewhere. Try running a magnet over the point where the cold feed enters the system, if it sticks well, its highly likely its full of magnetite. Ive removed plenty of blockages from this point of the system and usually recommend good powerflush to go with it. Also,as above make sure the vent is high enough above the F&E tank.