- Messages
- 8
Background
10 year old system. Has been kept scrupulously clean. Kept very up to date with inhibitor (higher than normal concentration). Several rads have been removed, flushed and then additional inhibitor added to keep concentration high. Aladdin Self-bleed vents fitted upstairs and down (5 up down, 10 in total). Honeywell TRV's - all working normally. No leaks. Pressure good and holding firm at 1.5bar.
Problem
So, when firing up, and indeed sometimes when system hot I get a clicking sound in a few of the rads. The noise is mostly in the downstairs "bypass" rad - which has normal locksheild valves on both sides. This is NOT the "tick tick" of pipes heating, but the easy to recognise sound of micro bubbles perhaps pushing past the valve / TRV.
Sometimes, on some rads, I hear a larger "gurgle" which quickly clears. Note...ALL rads are very hot at the top. No air present when bleeding - even the ones that have been gurgling.. The Aladdins are new and seemingly OK.
I do however know that the boiler (ICOS HE24) self vent valve needs replacing...but cannot imagine how this admits air.
Not all rads do it... the ones that do make the noise, do not do it all of the time.
I'm confused ! - welcome any help.
10 year old system. Has been kept scrupulously clean. Kept very up to date with inhibitor (higher than normal concentration). Several rads have been removed, flushed and then additional inhibitor added to keep concentration high. Aladdin Self-bleed vents fitted upstairs and down (5 up down, 10 in total). Honeywell TRV's - all working normally. No leaks. Pressure good and holding firm at 1.5bar.
Problem
So, when firing up, and indeed sometimes when system hot I get a clicking sound in a few of the rads. The noise is mostly in the downstairs "bypass" rad - which has normal locksheild valves on both sides. This is NOT the "tick tick" of pipes heating, but the easy to recognise sound of micro bubbles perhaps pushing past the valve / TRV.
Sometimes, on some rads, I hear a larger "gurgle" which quickly clears. Note...ALL rads are very hot at the top. No air present when bleeding - even the ones that have been gurgling.. The Aladdins are new and seemingly OK.
I do however know that the boiler (ICOS HE24) self vent valve needs replacing...but cannot imagine how this admits air.
Not all rads do it... the ones that do make the noise, do not do it all of the time.
I'm confused ! - welcome any help.