Gotta bleed my radiators(air in them) should the heating be on or off(combi boiler system)?

Answer 1

The installer did'nt put inhibitor into the system hence having to let out the "air"
This is not air but hydrogen gas+Hydrogen sulphide gas formed because of the dissimilar metals in the system.the Sacrificial Anode (the radiators) get eaten away.
CURE :- put inhibitor into the system, the original installer hopes that you will call him back in as little as 5 years
FERNOX IS ONE OF THE BETTER ONES
Notice to SPOCK7876 your mailbox is blocked.

Answer 2

ummm....I worked for a heating and air conditioning company, actually, two of them, here in the U.S.A. and we always pressurizied them to a pressure of 12 p.s.i. We would bleed them from the lowest radiator to the highest radiator. I have never heard of a "combi" boiler system. Is that some kind of a wood and coal burner with an oil burner attached to it?? IM me and let me know plz. Oh yeah, I almost forgot....We would always bleed the system while it was turned on, with the circulator pump running, but the burner disabled so as no heat would be bieng generated....Just remember that you should NEVER flood a hot boiler (hot bieng over 125 degrees F.) with cold water...It could crack the boiler jacket, or seperate the sections of the boiler.

Answer 3

It don't matter, but off ideally. When air is warm its expands and you don't wont to scald your hands when the water comes out the radiator!!... Bleed the one down stairs first then go up starts. Bleed them till the water just starts to trickle out. When you have done them all make sure you then fill your combi system back up to about 1- 1.5 bars. Remember the pressure will rise in your boiler as the heating gets warmer.

Hope this helps you out.

Answer 4

I have found that having the boiler and pump working helps to expel the air quicker. Although to be honest I don't think it matters. Have a cloth ready to soak up the water that comes out as it can be a nasty colour and stain any carpet below the bleed valve. Make sure you check that the pressure has not dropped as well. It should be running at about 30 psi just over 2bar.

Answer 5

Turn radiators on; once they are hot bleed the radiator furthest away from the boiler first until radiator coolant but no air comes out, then bleed each radiator in turn finishing with the one nearest the boiler. If you've done it right then all radiators should be uniformly hot from top to bottom.

Answer 6

The heating should be "on" dont forget to pressurise the system again after bleeding " It should be pressurised to about >2 bars = 28 lbs per psi.to do this open the taps on the link pipe at the bottom of the boiler and watch the guage on the boiler ! close the taps after !

Answer 7

you can turn them off only the thing is if they are on the water will be hot in the radiators and you usually have a leader radiator start up stairs first and work your way down when you have done feel the radiator at the bottom and it will be getting hot if not do it again hope this helps

Answer 8

Makes no difference. You should only have air in the highest radiator in the system unless you have recently filled it up. Remember to bleed the pump if accessible.

Answer 9

heating should be on otherwise the water is not being pumped round and at the end check (combi) that the water pressure in the combi is 1 bar good luck any problems email me

Answer 10

Better to turn the system off as you may use all the spare water in the system. IE. the pressure will drop. this could allow the pump to run dry and that could be expensive. When finished remember to top the system back up to 1.0 - 1.5 bar on th gauge.

CORGI reg installer