Vokera Linea 28 Pressure Problem

[descole]

When the boiler is cold the pressure gauge reads just below 0.5 bar and is stable. When the boiler is running, pressure rises to 2.5 bar.

Everything seems to function ok.

I re-pressurise the boiler whilst cold to 1 bar. When the boiler again operates pressure rises to 3 bar and the safety valve opens (new safety valve fitted) - otherwise the boiler continues to function as normal.

When the boiler is again cold, pressure is back to just below 0.5 bar.

Is there a blockage in the pipework between the expansion vessel (vessel pressure is 1 bar and air emits from the schraeder valve) and the aav. Is it easy and safe to remove and unblock? Greatly appreciate some advice and steps necessary to resolve this as I have trawled all the other parts of the forum looking for tips.

 

[kevplumb]

could well be worth a look

isolate and drain the boiler first

 

[Paul Barker]

I think blocked pipe is known about on those.

Temporarily drain off some water from the drain cock and open one rad's bleed valve (spare room for instance). When you refill don't bleed that rad.

Will act as an expansion vessel, and still gets warm at bottom.

 

[descole]

I think I may have solved the problem or at least one major issue

I drained the boiler then removed the braided pipe between the expansion vessel and the aav. The pipe was completely blocked at one end with very fine - compacted black dirt. I unblocked the pipe using a piece of wire by forcing it through the pipe until it was cleared. This took some time!

After, I re-pressurised the boiler and bled all radiators I fired-up the boiler and monitored it for a few days. The pressure is now stable at 1 bar when cold and reaches a maximum of 1.5 bar during operation.

Hopefully this is okay. Many thanks for your support

 

[sawadee]

i think i may have the same problem after reading this post how do you dain the boiler

 

[gas4you]

You will have to find a suitable drain cock in the pipe work under the boiler.

Unfortunately Vokers did not provide a draining point on these, instead giving the awful advice in the MI's of draining it through the PRV, which we all know is a no no, so do not do it like this unless you are prepared to have to fit a new prv