Bleedin' Radiators

[mark]

I'm forever having to bleed radiators. Does this mean that there is a water leak equal to the volume of air being bled. Assuming there has been no work done on the system can air get into the system by other means?

mark

[Dave Liquorice]

[Tabby]

1. need inhibitor
2. system pumping over
3. leak, less likely

NT

[A Plumber]

1. need inhibitor
2. system pumping over
3. leak, less likely

NT

A leaks most likely to me, unless the pump is pulling in, or pumping over

[Gary]

[John Rumm]

is yours a sealed or vented system?

[mark]

Thank you. Not sure who the target audience is for that article.

mark

[mark]

1. need inhibitor
2. system pumping over
3. leak, less likely

I'll get some inhibitor. What do you mean by pumping over, pump running to fast?

Thanks

mark

[mark]

Vented.

mark

[Man at B&Q]

How does that help? Is it that the corrosion products collect at the top of a rad?

MBQ

[Tabby]

Pumping over means the pump pushes water up out of the expansion pipe into the header tank, thus aerating it. The disoslved oxygen then comes out when hated, and collects in radiators. Reducing pump speed is sometimes the solution.

NT

[Tabby]

With no inhibitor, iron corrodes to magnetite, liberating hydrogen, and this is what collects in the rads.

NT

[John Rumm]

One that might hopefully finish it one day... ;-)

[Tabby]

Is it possible for there to be both air AND hydrogen in rads? First thoughts would suggest so, in which case maybe lighter testing could be, er, instructive in unexpected ways.

NT