My heater stops pushing hot water through the heating loop. The symptoms can be addressed by bleeding the system which always produces a lot of air coming out. The heating works for about 24 hours until air block is developed again. The heater pushes water from a basement to 3rd floor. The pressure shows about 24psi.
So far I've done:
- replaced air vent assembly and installed two additional small
Caleffi air vent on radiators upstairs. - replaced old 007-F5 circulation pump with a new one.
without any sign of improvement. I wonder if anyone could point me to the right direction.
Best Answer
This is, in my experience, nearly always an indication of leaks in the system, so make-up water is being added by the boiler feeder (adding new dissolved air) or, if the boiler feeder is shut off, air gets in after water leaks out. In a system without leaks, once the dissolved air introduced with new water is removed there should be no further need to bleed it.
Apart from the inconvenience of having it stop working, the constant addition of new water with dissolved air also violates the assumption that when the system is sealed there's no more oxygen added to promote rusting of the iron components once it's either bled out or rusted a little.