What is small orange cylinder? - is system pressurised?

Have a potterton gas wall mounted boiler in the attic, one cold water tank feeding a (vented) hot water cylinder with an emersion heater. Have not been using central heating over the summer but have just moved a rad and tried firing the system up to test for leaks.

Situation is complicated because I wasn't sure of refilling procedure if the rads weren't emptied: I keep them locked off as I heard this was a good idea, though on coming to fill the system it didn't go to plan!

So, now the boiler won't light, the pump is making promising noises and water is trickling from the rads when I bleed them. So I'm thinking maybe there's an airlock in the boiler?

Its powered off now, but I'd like to fix it tomorrow if poss...

... so I'm wondering, why didn't the system fill properly? Is it because the of the strange orange mini cylinder with what looks like a pressure guage and a fill loop (about 10 inches high and 12 wide, with a red knob on the top) ... could it be pressurised??! ... next to the boiler?

I've always kind of ignored its pressence in favour of assuming the central heating system was conventional, but now it seems I've got to bleed something else - the two pipes at the top of the boiler? Top up the orange thing? .. I'm beginning to wonder. (Didn't check the pressure before hand, currently just over 1.5...)

In the past to relight the boiler I just pressed reset. This now isn't working. Any suggestions much appreciated. I won't be able to post model numbers / photos until tomorrow evening.


Cheers chaps.

Piccy from memory - mother in law up there asleep right now - shouldn't really disturb her!!!

The orange thing is an expansion vessel. You have a sealed system and you will need to restore the pressure using the filling loop. You can find more details in the FAQ topic above.

Cheers boss. Dos mojitos por fabor?

Ended up here:
http://www.makewrite.demon.co.uk/SealedCH.html

Pressurise, bleed.. pressurise, bleed. Thanks again for the pointer,

I think that your failure originally was to be unaware of the system pressure dial gauge which your system should have.

It should be set at about 1.5 Bar cold and increase a little when the system is hot.

Tony

Agile said:

I think that your failure originally was to be unaware of the system pressure dial gauge which your system should have.

It should be set at about 1.5 Bar cold and increase a little when the system is hot.

Tony

Click to expand...

Thanks like I don't already feel stupid enough

Its a potterton suprima 50, currently at 1.1 and the boiler does not stay lit. Was intending to increase pressure, but couldn't find recommended level in those instructions that I have from previous owner..

Cheers.

It should be set at about 1.5 Bar cold and increase a little when the system is hot.

If the boiler is still not working then it may have a reddish overheat stat on the front bottom edge. If so then this can be reset by pressing the center jently until it clicks. It may have a screw on cover.

Tony