how do i purge a 55lt keg?

[jeddog]

After I fill the keg with yummy beer how do I purge the air from a 55lt keg.

I have one of these

 

[rehabs_for_quitters]

I would think you'd have to purge the keg with CO2 first before filling the keg with said yummy beer

 

[Maheel]

can you remove the spear and just trickle in some across the top of the beer via some beer line stuck in ?

as co2 is heavier than air it should displace most of the air in there

 

[jeddog]

yeah i do that. I clean keg then starsan then fill with CO2 then fill with said yummy beer then add spear while I'm add more CO2.

can't do better than that..

 

[MaltyHops]

can you remove the spear and just trickle in some across the top of the beer via some beer line stuck in ?

as co2 is heavier than air it should displace most of the air in there

No, no, no ... no, we've got to lay this myth of co2 displacing air because it's heavier - see THE LEGEND OF CARBON DIOXIDE HEAVINESS.

You can get pools of deadly co2 under some conditions but if you put co2 in a container with air, they will mix evenly.

You will have to waste a lot of co2 by many charging/discharging into a filled keg to lower the o2 level somewhat.

Or use what might be called the fluid pre-fill flush method.

 

[Crusty]

After I fill the keg with yummy beer how do I purge the air from a 55lt keg.

I have one of these

IMG_4967.JPG

You can displace the air simply by unscrewing the gas in post slightly & then tighten it back up.
I purcased an A & D Micro Matic coupler with PRV. It's ideal for what you want to do. Fill up the keg, pressurise & pull on the PRV ring to displace the trapped oxygen. I'm selling a brand new D type coupler on ebay at the moment simply because I went the A type kegs & have no need for it. Here you go.