Pressure gauge problem

[nabby68]

This thread was originally titled "sludge remover" but I've decided to start a new thread as its a different issue




I have a Worcester combi 24cdi boiler

Ok I've used sentinel x800 in the system and seemed to be running better. I've always had a dodgy pressure gauge, in the sense that it's never moved when topping the system up so I've had to do it by "ear" with some guesswork involved. SoI've decided to replace it while I drain the system to put inhibitor in.
I've replaced pressure gauge and topped system up whilst observing pressure gauge and lo and behold the same problem. After topping system up for a good two minutes then bleeding then topping up the pressure gauge has hardly moved and sits at about 0.3 of a bar.
Any ideas as to why this is happening?

 

[45yearsagasman]

When replacing the gauge, did you unblock the orifice that the capillary connects to? That's where it gets blocked.

 

[nabby68]

Thanks for reply Pete

No. I didn't think to unblock it as I thought it was a case of the thin copper tube that links one end to the boiler and the other to the gauge of being blocked

How do I unblock the orifice?

 

[45yearsagasman]

You remove the capillary connection at the block and use a thin pin or screwdriver to clear the blockage. Reduce the system pressure first otherwise a jet of water will shoot out, although that's not a bad thing to happen as it will expel the debris. Just be prepared for it and protect the electrics.

 

[nabby68]

Would I be better to totally drain the system?

 

[45yearsagasman]

Bit ott to drain entire system, and a waste of inhibitor.

 

[nabby68]

So just drain a little off to relieve pressure? Will a lot of water not come out when I remove capillary end from boiler?

 

[nabby68]

Anyone?