Topping up Water Pressure - Biasi combi boiler

[livinginhope]

I have a biasi combi boiler (not certain of the model, but looking at the pictures on the biasi website it appears to be a Parva), and the water pressure has fallen to 0.2bar (!) (Very suddenly over the last week, until then it's sat just over 1 bar in the entire year and a bit that I've had it).

I've topped up water pressure on (older) boilers loads of times before - it's always been a simple matter of opening the valve on a water inlet until the guage hits the required pressure. But on this boiler, the PDF of the manual that I downloaded from biasi.com is telling me to fit a temporary hose between the cold water inlet and the ch return and open the valves on those pipes. I'm baffled - I don't have temporary hose, neither pipe seems to have any attachment that would allow me to fit such a hose even if I had it, and the ch return pipe doesn't have a valve to open either.

This looks like a job that's way beyond my capabilities as an ordinary homeowner and requires a gas engineer. But surely I'm not supposed to call out a gas engineer merely to top up water pressure? Am I? Have I misunderstood something?

Any pointers appreciated, ta!

Also, is it OK to leave the boiler running for a few days with that low pressure, until I can get the problem sorted, or is it dangerous/urgent/something that I must sort out asap?

Thanks!

 

[gas4you]

There should be a filling loop somewhere under your boiler.

If not straightway obvious, you may have to delve a bit deeper to find it

 

[livinginhope]

Thanks Dave!

What would a filling loop look like?

 

[gas4you]

Search FAQ's, I'm sure there must be a pic of one in there