Boiler noise, help needed

[joe-90]

I think you are confusing chemistry for physics.

When you reconnect a filling loop it just HAS to have air in it (physics). When you turn the tap on that air is injected into the system.(physics).

THAT is the air you THINK is in solution.

 

[MIGEM]

My kitchen tap has a 3/4 inch rubber washer at the end of a 14 inch spout, where the bubbles turn to atmosphere in the spout, which is rather different to the 6mm brass cone at the end of the OP's filling tap on his boiler, but when he gets home from work, he can check that.

 

[MIGEM]

I think you are confusing chemistry for physics.

When you reconnect a filling loop it just HAS to have air in it (physics). When you turn the tap on that air is injected into the system.(physics).

THAT is the air you THINK is in solution.

So do radiators, unless yours come pre-filled. That is the air you bleed out of the system. The boiler comes with air in it.

 

[joe-90]

But you said: "Topping the boiler up 0.2 bar, by only just cracking open the filling tap, more often than not, just fills it with aerated water and can sometimes add to a problem of trapped air."

What does that have to do with air in the rads?

 

[MIGEM]

The filling loop has air in it..... (Loop) Not his integral link)
the boiler comes with air in it, the pipe/tube, rads all have air in them. That is bled out when the system is filled. The OP is not talking about having trapped air.
I stated 'introducing air' to a filled system.

 

[joe-90]

You said: "by only just cracking open the filling tap,"

If you are referring to a saturated solution then that action will add an amount so small it would be difficult to measure - or in general terms - negligible.

 

[Agile]

Carbon dioxide is very soluble in water, oxygen much less so and nitrogen only slightly.

CO² will immediately come out of solution when the pressure is reduced, O² somewhat slower.

But all of this is rather irrelevant in relation to heating systems. Small amounts of air will dissolve in the heating water over a few days.

The oxygen will over time react with iron and some oxides and will be taken out of the water.

Tony

 

[MIGEM]

'More often than not'
If someone is topping up their boiler 0.2 of a bar, it will have an impact, more often than not.
Granted, the air that has flown through a full bore valve will also remain in the system and dissolve into the system, but do you have a point Mr Beverley?

 

[MIGEM]

Thank you Agile

 

[joe-90]

Why are you thanking him? He's agreeing with me - not you.

 

[MIGEM]

Removing the plug from the front of the pump will introduce more air than the filling tap, so thats hardly an issue. The fact is, it can be. Im well aware of the physics of it all.

 

[joe-90]

Well I'm glad I've taught you something.

You can thank me if you like.

 

[MIGEM]

Youre ok, but give my love to Danielle.