Worcester greenstar 28i junior pressure on 0 but boiler is working fine

[lockrock]

Hi,

I have the Worcester greenstar 28i junior which was installed by a previous owner in 2008, we haven't had it serviced in maybe 4 years (stupid I know). It's been working fine but within the last year the pressure gauge has dropped to 0 and using the key method to increase the pressure doesn't work anymore. I haven't found any leaks on the boiler or around any of the radiator valves.

Would anybody be able to tell me what is the likely issue is, as I've looked around but cannot find a case that matches mine.

I hope someone can point me in the right direction of what might be wrong, the boiler is installed in an awkward location in the kitchen and I might have to remove cupboard boards to allow access to the top of the boiler for professional access.

Any help would be greatly appreciated, thank you!

 

[terryplumb]

Are you sure you are correctly opening the filling loop ?
Has pressure dropped suddenly ,or over a long period of time ?

 

[lockrock]

Thank you for the reply terryplumb.

You're right and I wasn't getting the key in properly, so I did get the key in and loosened the white square nut to the left and I was able to bring the pressure up to 1.5. Then when tightening the white square quite a lot of water came out to a point where I though it might not stop and the pressure was lost by the time I managed to tighten it and remove the key.
I'm hesitant to try again.

 

[terryplumb]

What is the pressure on the gauge ?
It doesn't need to be 1.5 bar.
1 bar is enough.
Closing the white nut and then removing the key sometimes allows a tiny amount of water out ,but nothing that will significantly drop the pressure. You must close the white nut before removing the key.
If you are doing it this way ,and lots of water comes out you will either need to replace the integral filling loop ,or fit a seperate remote filling loop.

 

[lockrock]

Hi terryplumb, I've had a another go with the key and managed to increase the pressure to just above one, then hand tighten the white nut (I think I might have over tightened it with pliers last time) and finally remove the key and it seems to be fine now. Thank you for your help. I'll leave it now until I get it serviced.