Auto air vent question

[markyhud]

For years I've had the following auto air vent in the airing cupboard.

It tends to weep when set to the open position and so today I've fitted this Honeywell EA122 jobby.

It vented automatically as it should when refilling the system but with a manual vent I was able to shift more stubborn air after a few hours. I did see in the instructions that it should be positioned on the positive side of the system. Is this referring to a combi boiler setup? It's positioned on the return from the coil. Any thoughts? I think it's just a case of letting it do it's thing over the next few days

 

[Simon F]

the positive refers to where it is on the system in relation to the pump.
(and depending on where the fill/vent is situated)
after the pump on the flow side is positive,
so the water will be giving positive pressure rather than the possibility of having a pulling effect on the negative side of the system, ie before the pump

 

[markyhud]

the positive refers to where it is on the system in relation to the pump.
(and depending on where the fill/vent is situated)
after the pump on the flow side is positive,
so the water will be giving positive pressure rather than the possibility of having a pulling effect on the negative side of the system, ie before the pump

That's great thanks as this vent is after the pump. Cheers

 

[Chalked]

Need to be fitted vertically too, the float can stick open or shut when mounted like that.

 

[markyhud]

Need to be fitted vertically too, the float can stick open or shut when mounted like that.

Balls! Knew it was too good to be true. Would I be better sticking with the cheaper type I did have?
What happens if the float sticks? Does it just stop venting?

 

[Chalked]

East fix is two 1/2" bsp male and female elbows fitted together and into the vent connection will get rid of the angle.
MALLEABLE IRON & STEEL, BSP THREADED FITTINGS

 

[markyhud]

East fix is two 1/2" bsp male and female elbows fitted together and into the vent connection will get rid of the angle.
MALLEABLE IRON & STEEL, BSP THREADED FITTINGS

Sorry but as an amateur what exactly is a malleable fitting and how do they go together to get rid of the angle? I would rather give something like this a go and stick with the new vent than go back to the cheaper type

 

[Chalked]

Sorry but as an amateur what exactly is a malleable fitting and how do they go together to get rid of the angle? I would rather give something like this a go and stick with the new vent than go back to the cheaper type

drain the heating down to below the air vent and remove, p.t.f.e both male ends of the elbows, screw the first into the fitting you have the air vent fitted into, this is tightened until it points in your case 90 degrees to the right. Then screw the second elbow into the first and tighten until it is tight and points vertically. Then refit the auto air vent into this.

quite hard to describe by text but get two from your local merchant and it will make sense.

 

[Reg Man]

It looks like its on the flow not the return, unless you have reversed the pipes. Why are you getting so much air would be a better question? What is the open vent cold feed arrangement?

 

[markyhud]

drain the heating down to below the air vent and remove, p.t.f.e both male ends of the elbows, screw the first into the fitting you have the air vent fitted into, this is tightened until it points in your case 90 degrees to the right. Then screw the second elbow into the first and tighten until it is tight and points vertically. Then refit the auto air vent into this.

quite hard to describe by text but get two from your local merchant and it will make sense.

I did go to bed a bit confused but then had a light bulb moment about this and that was exactly what I was thinking. Cheers!

 

[markyhud]

It looks like its on the flow not the return, unless you have reversed the pipes. Why are you getting so much air would be a better question? What is the open vent cold feed arrangement?

Our house was newly built 14 year ago. From what I gather the system is poorly configured. A neighbour in the same style house got British Gas out to see about cover and they said they wouldn't cover it because it was poorly designed!! However it has got gradually noisier over the years and I've just ignored it really. There has never been any kind of cleaner or inhibitor added either. So I've cleaned it using F3 (loads of magnetite/rubbish) and adjusted the level of the water in the f&e tank as it was about 3/4 full when cold. There is only about 300mm between the level of the water and the top of the vent pipe so think this might need adjusted. These two things have made a definite improvement and changing the rubbish cheap AAV was my next step. I do still think I need a professional to check things out and I plan to do this along with having a filter fitted next year.

 

[IDCHAPPY]

I hope you didn't fill your feed & expansion tank too much? there has to be some room for system expansion in there when the system is hot

 

[markyhud]

I hope you didn't fill your feed & expansion tank too much? there has to be some room for system expansion in there when the system is hot

No I bent the ballcock to lower the amount as the level was far too high. It's about 1/3 full when cold now and seems lots quieter. Not sure if air was being drawn down the vent pipe when it was fuller

 

[IDCHAPPY]

Auto Air Vents are generally pretty good mate, need cleaned out every few years as the can tend to stick with crap build up in them

 

[markyhud]

Well this new one seems much more efficient. The old one used to weep. I'm going to follow the advice from Chalked and try and buy a couple of elbow threaded joints to get it installed vertically

 

[Reg Man]

No I bent the ballcock to lower the amount as the level was far too high. It's about 1/3 full when cold now and seems lots quieter. Not sure if air was being drawn down the vent pipe when it was fuller

Probably full again now. I think your cold feed and open vent go into the system in the wrong place and its circulating and drawing air into the system.

 

[markyhud]

Probably full again now. I think your cold feed and open vent go into the system in the wrong place and its circulating and drawing air into the system.

Do you mean the configuration in the loft and the pipework into the f&e tank? I do believe that air may be drawn down the vent pipe as it has been noisy on start up but is quiet again after about 30 seconds. I do think the vent pipe needs to be higher above the level of the water in the tank. Is this what you mean?