pressure low on greenstar cdi compact

[boilerfrustration]

My boiler is a Greenstar CDi Compact. The boiler is working but I've noticed the hot was sometimes cutting out and turning to cold. Looking at the pressure gauge on the boiler, I've spotted the needle is at zero. I've tried to put back the pressure by following the instructions in the manual but no response. I've inserted the plastic key firmly in under the open padlock. Turned it to the closed padlock. Then turned the white knob next to the key to the left to open the water supply. But the gauge remains at zero. Can any one suggest what I'm doing wrong?

 

[boilerfrustration]

Just to correct the information I gave above. I've inserted the white key below the open padlock. Then turned it to the closed padlock. Then turned the white knob to the left to open the water supply. I cannot hear the boiler filling and the needle remains at zero.

 

[boilerfrustration]

I've now managed to restore pressure. It seemed I hadn't fully inserted the white key. However, there is still a fault. Code E4 376 is displayed on the screen. Can anyone advise what this means? Thankyou.

 

[mikeyd]

Preheat sensor on DHW Inlet Open Circuit
From page 60 of this manual https://www.google.co.uk/url?sa=t&r...rXUOPkRbArShALQ&bvm=bv.97653015,d.ZGU&cad=rja

 

[boilerfrustration]

Thank you for the reference. As a layperson, is there anything I can do to correct the problem?

 

[simond]

I suggest you turn the power off to the boiler, wait a short time and re power it up. Sometimes you get some spurious codes when there is little water in the boiler.

The Worcester filling link is incredibly difficult to use, they've only just got round to replacing it.

Those padlock symbols aren't easy to see particularly if you are old, and it is difficult to know when the key is fully inserted. All been resolved now, you can get a fitter to have the later push button filling system retro fitted.