Sanke home system, having foam issues, please help

[Wyobrew22]

I have been running sanke kegs for about a year now on my 2 tap kegerator and have been unable to work out the kinks myself after much trial and error. 100% foam pours and flat beers have me pulling my hair out and I would appreciate any advice. This is a standard cheap kegerator meant to hold 1 full size sanke keg. I modified the tower to accommodate 2 faucets. 1 regular perlick and 1 flow control. I force carb new beers at 35 psi for 24 hours and then drop pressure to 12 psi. I seem to always have a keg that settles pressure nicely with properly carbed beer and the other will just foam like crazy.
Using 3/16 inner diameter beverage tubing I have tried run lengths of 3,5,10 and 12 feet for the beer lines at serving pressures of 5, 10 and 15 psi with no combination showing any real improvement. I have switched couplers, bought new ones, and tried each keg and each coupler with each faucet.
One specific variable I would like knowledge on and can’t seem to find info is regarding one of my two kegs, it was originally a sanke WINE keg and somehow I just noticed this. Is there something different in the spear/valve that would knock all the co2 out of solution? The foamy beers are always carbed in exactly the same manner but never taste/feel carbonated in the glass. They will pour a 20oz glass full of foam with about a finger of beer at the bottom, I can see a fair amount of bubbles throughout the line. Single bubbles very slowly coming into the line from the keg side when not pouring and mostly foam entering the line from the keg end when pouring. I usually pour just a bit at a time until I can get it to settle to 2/3 of a glass or so, give up and drink the semi-flat beer. I had never noticed if it was the specific wine keg I was getting all foam from but I really have no other ideas at this point. Any helpful info or experience? I don’t brew too often but next time I keg I will for sure take notice if it’s the wine keg that foams again. Or, am I just getting un-lucky and over-carbing one of the two somehow?

 

[tll77]

Sanke kegs for wine or coffee, etc. are the same as kegs used for beer. Same coupler also.
If you have bubbles in the liquid line you should check all the seals in both the keg and the coupler. Make sure there are no nick or holes in the EPDM seal around the check ball(sometimes not a ball but a domed poppet). Then check that the seals on the probe of the coupler are intact and in good shape.
I guess it could be a bad washer at the beer nut on the coupler but that is unlikely as you would probably notice beer leaking there.

 

[SassyGlass]

I have been running sanke kegs for about a year now on my 2 tap kegerator and have been unable to work out the kinks myself after much trial and error. 100% foam pours and flat beers have me pulling my hair out and I would appreciate any advice. This is a standard cheap kegerator meant to hold 1 full size sanke keg. I modified the tower to accommodate 2 faucets. 1 regular perlick and 1 flow control. I force carb new beers at 35 psi for 24 hours and then drop pressure to 12 psi. I seem to always have a keg that settles pressure nicely with properly carbed beer and the other will just foam like crazy.
Using 3/16 inner diameter beverage tubing I have tried run lengths of 3,5,10 and 12 feet for the beer lines at serving pressures of 5, 10 and 15 psi with no combination showing any real improvement. I have switched couplers, bought new ones, and tried each keg and each coupler with each faucet.
One specific variable I would like knowledge on and can’t seem to find info is regarding one of my two kegs, it was originally a sanke WINE keg and somehow I just noticed this. Is there something different in the spear/valve that would knock all the co2 out of solution? The foamy beers are always carbed in exactly the same manner but never taste/feel carbonated in the glass. They will pour a 20oz glass full of foam with about a finger of beer at the bottom, I can see a fair amount of bubbles throughout the line. Single bubbles very slowly coming into the line from the keg side when not pouring and mostly foam entering the line from the keg end when pouring. I usually pour just a bit at a time until I can get it to settle to 2/3 of a glass or so, give up and drink the semi-flat beer. I had never noticed if it was the specific wine keg I was getting all foam from but I really have no other ideas at this point. Any helpful info or experience? I don’t brew too often but next time I keg I will for sure take notice if it’s the wine keg that foams again. Or, am I just getting un-lucky and over-carbing one of the two somehow?

I agree with tll77. I recently had a similar problem as you WyoBrew. I had one of my kegs pour all foam followed by flat beer. It ended up being that I was totally missing the o-ring on my diptube for the liquid "out" side. After I put one on I immediately went back to a normal keg pouring as it should. I purged the line a little. That taught me the importance of those o-rings and washers for sure!

 

[Qhrumphf]

Is it always a particular keg, or a particular coupler, or a particular line, or faucet? Isolating will narrow it down dramatically.

If it's always the same coupler or line, you may have leaky or damaged fittings/o rings that may seal under pressure but leak and draw air in or allow gas breakout when pouring.

If it's always the same keg, then that points to a problem with the keg. The seals in the valve are easy to damage, and if you don't know to inspect them you may not notice. If the seal between gas and liquid is damaged (very common), instead of going into the keg CO2 just shoots into the beer line causing foaming.

There are also different valve/coupler designs. Most US brewers use D-type, but not all (and once you go import other types are more common). If you're connecting incompatible couplers and kegs that could well be your issue.

 

[Wyobrew22]

The issue seems to be with one keg as I have tried every combination of line/keg/coupler/faucet. I have a new kegco coupler that I hate and thought it might be the issue, it doesn’t twist down onto the spear nearly as far as the other coupler I have and the up/down portion of the handle won’t move after being locked into the spear, not allowing it to be un-coupled before twisting it off of the keg.....separate issue but I have it on the non-foaming keg now and it’s working fine.
I re-did my lines last night at 10ft. Poured a few beers, still all foam etc. but noticed this morning that the beer line on that keg has virtually no liquid in it, just a spot here and there throughout the coil of beverage tubing. This would seem to indicate the keg seal. I will look for a rebuild kit I think.

 

[day_trippr]

[...]It ended up being that I was totally missing the o-ring on my diptube for the liquid "out" side.[...]

Yep, that's a classic cornelius keg failure mode, and it's good to experience it so it'll be recognized the next time.
The OP has sanke kegs, and likely has the same issue but in a sanke form factor (everything is totally different)...

Cheers!

 

[Qhrumphf]

The issue seems to be with one keg as I have tried every combination of line/keg/coupler/faucet. I have a new kegco coupler that I hate and thought it might be the issue, it doesn’t twist down onto the spear nearly as far as the other coupler I have and the up/down portion of the handle won’t move after being locked into the spear, not allowing it to be un-coupled before twisting it off of the keg.....separate issue but I have it on the non-foaming keg now and it’s working fine.
I re-did my lines last night at 10ft. Poured a few beers, still all foam etc. but noticed this morning that the beer line on that keg has virtually no liquid in it, just a spot here and there throughout the coil of beverage tubing. This would seem to indicate the keg seal. I will look for a rebuild kit I think.

Can you verify that your kegs and couplers are all D-type? Do you get a beer shower connecting them?

An S-type coupler (some German kegs) can be forced onto a D-type spear valve (and the valves look fairly similar, at least compared to other types...). The coupler probe is longer (they look even more similar than the keg valves- that slight probe length is really it), can spray a bit connecting, and can damage the gaskets on the keg (which could in turn cause the foaming issue). I don't know if it's harder to get off too but wouldn't surprise me.

 

[tll77]

The issue seems to be with one keg as I have tried every combination of line/keg/coupler/faucet. I have a new kegco coupler that I hate

Let's determine if it is the keg or the coupler. Photos could help us narrow this down for you more quickly.
But, @Qhrumphf has a great point an S type coupler has the same body as a D type and will twist into the spear however it will not engage the poppet properly.
Here is a side by side(or top and bottom) top D type bottom S type

Notice the same body on the two couplers in fact they are interchangeable but the probe is different enough to not properly engage the poppet.

 

[Wyobrew22]

Sorry it took a few days to reply, really busy with work. Here are some pictures of my two couplers. They are definitely different. The first two pics are the older coupler that I like and the third pic is the new kegco that doesn’t thread properly. The kegco appears to be a “d” type and the older one looks more like an “s” but not exactly like the photos posted above. The poppet engagement piece does not stick below the gasket in the open or closed position. It appears to have a thick gasket that extends all the way to the end of poppet engagement point but the metal piece appears to be shaped like the “s” posted above. Not sure this is the issue though as both dispense fine on one keg and both foam like crazy on the other. Inspected both keg coupler seals for cuts and didn’t see anything there. Have to wait until empty to look at the o ring. No beer shower with connection on either, but the old coupler twists moderately easily all the way to the stop position on both kegs and the kegco coupler only twists onto each keg maybe 1/3rd of the way to the stop. Verified both kegs are “d” type. I’m even more confused now though. How can I have two different style couplers that work fine on one keg? J

 

[crane]

I have the same issue with 1 of my sanke kegs. The rubber seal on the top of the spear is not nearly as soft as the other kegs I have. I have found that a little keg lube on the top surface helps it seal better to the coupler. This one seal is what separates the gas going in from the liquid going out. If it doesn't seal correctly then you end up with excess CO2 in the liquid line.

This is the equivalent to the classic corny keg failure mentioned above. The failure of this one seal has the same end result.