Central heating - no pressure?!

stifz

Hi All,

recently got a new oil burner and installed it connecting flow & return pipes etc. bled the oil valve - all good. bled the water pump - all good i think?!

It doesn't seem to keep pressure though and the upstairs radiators seem only 1/4 full. If i use the bleed valve nothing comes out not even a hiss of trapped air etc? The radiator sounds like a running tap??

any idea's coz it's bleed'n freez'n!

crosstownk

Every time you bleed the system you release pressure - this is possibly why you no longer hear a hiss. If you have a sealed system then you may need to open the filler valve to allow more water in and increase the pressure. Can you locate the pressure guage? It should be approx 1 bar with the system cold.

stifz

okay thanks, i know where the gauge is. So you reckon if i top up the system with more water and then bleed the rads i should be okay? The pressure was at zero before i even started to bleed the rads.. is this a another problem?

crosstownk

Pressure will be at zero if there is little or no water in the system. Just fill the system some more and then bleed the rads as you say. But remember that you will still need to top up as you bleed. Continue to bleed until only water comes out of every rad. There may also be an air vent at the top of the coil for your HWC - you may need to release air from here too. Also, once the system is up and running keep an eye on the guage when the system is cold as you may still get pockets of air moving about in the rads/pipework.

When I drained my system down last year to fit zone valves, it took a couple of months to get the pressure to settle down.

stifz

thanks for that.