Hi Longshanks
Maybe I've confused you a little....using the radiator bleed valve is a perfect way of reducing the pressure in your system. It takes a little while, and maybe a bit messy but its foolproof - you don't interfere with the pressure release valve so the chances of that playing up are minimal.
You only need to reduce the pressure to zero if you intend to check and maybe repressurise the expansion vessel with air.
So, if you want to reduce your pressure to - say - one bar, just bleed out water from the rad valve until you see that pressure on the gauge. There's no need to go lower and then bring the pressure up again with the filling loop - you would only use that facility if the pressure was low.
So.....a couple of tips to keep your boiler happy. Check the pressure in the expansion vessel yearly. Keep an eye on the boiler pressure...it should not rise or fall at all ideally - and make sure that filling loop is completely turned off. Even the slightest drip will over pressurise the system in a day or two.
Hope this helps! Have a good evening
John
Maybe I've confused you a little....using the radiator bleed valve is a perfect way of reducing the pressure in your system. It takes a little while, and maybe a bit messy but its foolproof - you don't interfere with the pressure release valve so the chances of that playing up are minimal.
You only need to reduce the pressure to zero if you intend to check and maybe repressurise the expansion vessel with air.
So, if you want to reduce your pressure to - say - one bar, just bleed out water from the rad valve until you see that pressure on the gauge. There's no need to go lower and then bring the pressure up again with the filling loop - you would only use that facility if the pressure was low.
So.....a couple of tips to keep your boiler happy. Check the pressure in the expansion vessel yearly. Keep an eye on the boiler pressure...it should not rise or fall at all ideally - and make sure that filling loop is completely turned off. Even the slightest drip will over pressurise the system in a day or two.
Hope this helps! Have a good evening
John