Beer from my keg is flat

[Christoff]

That^ is the main problem why your beer is flat when poured.

It takes time (hours, days, depending on the method used) for beer (or any liquid) to dissolve CO2 (and thus becoming carbonated), even under pressure. Without pressure it can't dissolve much CO2, resulting in flat beer.

Then temperature is important too. Beer at lower temps can hold much more dissolved CO2 than at higher temps. So the keg should be kept cold when carbonating, stored for later use, and while dispensing.


Is the rubber o-ring on the regular lid any different than the one from your special tap lid?
Are you using keglube on the o-rings? How tight do you screw that lid on?

You can probably see if there's a leak around the lid when spraying that area with starsan or submerging the keg in a bucket or tub with water.

No keg lube though I have been meaning to get some. It’s brand new so figured I had some time.

I totally forgot about the leak test. I do that for all my connections but for some reason hasn’t occurred to me for the mini keg.

 

[DuncB]

I'm confused can we have a reset here please a few questions to answer at a time. Once we are sure of the problem we will have a diagnosis and can make a cure for you and your keg of beer.

A) Do you put just less than one gallon of beer uncarbonated into the minikeg?

B) Then carbonate in a fridge using the regulator seen in your photos and CO2 from the little bulb?

Standing by.

 

[Christoff]

I'm confused can we have a reset here please a few questions to answer at a time. Once we are sure of the problem we will have a diagnosis and can make a cure for you and your keg of beer.

A) Do you put just less than one gallon of beer uncarbonated into the minikeg?

B) Then carbonate in a fridge using the regulator seen in your photos and CO2 from the little bulb?

Standing by.

I’ve only filled it twice. Both times it was a full gallon give or take an ounce or two.

I use the set up in the pic and put it in fridge temps (mini bar fridge or my very cold garage). Roughly 35-38 F. I have used only the pieces they provide so the tap, regulator and Co2 in the pic. As well as the 10” internal dip(?) tubing that came curled. Once it appears to have carbonated, put it in my back room at 50-55 depending on the outside temp. I’ve tried turning off the CO2 until I serve. I’ve kept it on at the prescribed psi and turn it down to serving pressure. After the first time it didn’t take, I tried again at warmer temps (as per the online info I found). Didn’t work and tried a third time, which prompted this thread.

 

[DuncB]

Thanks for info.
So one bulb are they 8g of CO2 size per gallon? To carbonate at 38 F approximately.

 

[DuncB]

Something like 18 gramme CO2 per gallon in beer at 2.5 vols
A full minikeg will have little headspace so difficult to get gas exchange and slow.
Shaking keg to accelerate this must only be done with a non return ball lock or gas side nrvalve otherwise you risk liquid getting into your regulator.
So more than 2 bulb to carbonate and more to serve.
This could explain why the beer is truly flat but not if you pour foam and it settles flat.
@doug293cz will correct my maths / approximation with a red pen.

I feel my numbers don't account for CO2 in beer at end of ferment.

 

[Christoff]

Thanks for info.
So one bulb are they 8g of CO2 size per gallon? To carbonate at 38 F approximately.

The bulb is 74 g

 

[doug293cz]

Something like 18 gramme CO2 per gallon in beer at 2.5 vols
A full minikeg will have little headspace so difficult to get gas exchange and slow.
Shaking keg to accelerate this must only be done with a non return ball lock or gas side nrvalve otherwise you risk liquid getting into your regulator.
So more than 2 bulb to carbonate and more to serve.
This could explain why the beer is truly flat but not if you pour foam and it settles flat.
@doug293cz will correct my maths / approximation with a red pen.

I feel my numbers don't account for CO2 in beer at end of ferment.

1 volume is 1.977 g/L of CO2, and 1 gal is 3.7854 L, so 1 gal @ 2.5 volumes would have 3.7854 * 1.977 * 2.5 = 18.7 g of dissolved CO2. Your estimate was pretty close.

Beer at the end of a fermentation @ 65°F will contain about 0.88 volumes of carbonation, so to carb to 2.5 volumes you need to add 1.62 volumes. That would be 3.7854 * 1.977 * 1.62 = 12.1 g CO2 additional CO2 required for carbonation.

The amount to serve will depend on serving pressure and temperature. To push 1 gal at 2.5 volumes and 40°F (4.44°C) would require a pressure of 12.2 psi, and use 3.7854 * 1.977 * ((14.7 + 12.2) / 14.7) * 273.15 / 277.59 = 13.5 g. For 1 gal at 2.5 volumes and 53°F (11.67°C) would require a pressure of 19.3 psi, and use 3.7854 * 1.977 * ((14.7 + 19.3) / 14.7) * 273.15 / 284.82 = 16.6 g.

Carbonating and serving @ 53°F will require 12.1 + 16.6 = 28.7 g of CO2. You will need a little CO2 for the headspace as well.

Brew on

 

[Christoff]

Something like 18 gramme CO2 per gallon in beer at 2.5 vols
A full minikeg will have little headspace so difficult to get gas exchange and slow.
Shaking keg to accelerate this must only be done with a non return ball lock or gas side nrvalve otherwise you risk liquid getting into your regulator.
So more than 2 bulb to carbonate and more to serve.
This could explain why the beer is truly flat but not if you pour foam and it settles flat.
@doug293cz will correct my maths / approximation with a red pen.

I feel my numbers don't account for CO2 in beer at end of ferment.

I’m curious about this headspace situation. The bulbs are big enough but I wonder if I filled it too much. This is a good possibility at first however I have since gradually drank the beer over the last couple months so by the time I got to the point of 20 psi, it was at least half empty. However I may not have shaken it as much given I’m irritated with this thing.

 

[doug293cz]

I’m curious about this headspace situation. The bulbs are big enough but I wonder if I filled it too much. This is a good possibility at first however I have since gradually drank the beer over the last couple months so by the time I got to the point of 20 psi, it was at least half empty. However I may not have shaken it as much given I’m irritated with this thing.

If you use a pressure regulator, you can't "overfill" the headspace. That's the purpose of the regulator.

Brew on

 

[Christoff]

If you use a pressure regulator, you can't "overfill" the headspace. That's the purpose of the regulator.

Brew on

Sorry, I meant with beer. And if I put too much beer in that reduces headspace. If it requires a certain amount of headspace to carbonate properly this could be part of it, though not all, I assume.

 

[doug293cz]

Sorry, I meant with beer. And if I put too much beer in that reduces headspace. If it requires a certain amount of headspace to carbonate properly this could be part of it, though not all, I assume.

Final level of carbonation doesn't care about the amount of headspace, but depending on the headspace geometry, the rate of carbonation may be affected. If you fill the beer higher than the constant diameter portion of the keg, the surface area of the beer which can absorb CO2 starts to rapidly diminish, and less area means a slower rate of CO2 absorption.

Brew on

 

[balrog]

I was going to say, you don't need any headspace to carbonate, but you'd need a lot more time if the only surface are for absorption were the diameter of the GAS IN port/tube/line.

 

[Christoff]

Final level of carbonation doesn't care about the amount of headspace, but depending on the headspace geometry, the rate of carbonation may be affected. If you fill the beer higher than the constant diameter portion of the keg, the surface area of the beer which can absorb CO2 starts to rapidly diminish, and less area means a slower rate of CO2 absorption.

Brew on

That makes sense. Thanks

 

[DuncB]

The bulb is 74 g

That's an unusual size, what physical dimensions is it? It only looks about 3 inches long in the photo and max one inch wide.
But there is a parallax effect going on.
The nearest to 74g I found on line was an 88g one that was

• Length: 176mm
• Width: 35.2mm
• Neck Length: 24.3mm
• Neck Width: 16mm
• Thread: M16 x 1.5 Not sure this thread would fit the mini regulator normally it's a

also said not food safe and was from hungary.

Found one that is 16g of CO2

Total weight 58gm. Size 88.6mm x 21.9mm


I have noted that you mention it is at 20 psi once half drunk this again changes the criteria on the calculators and would mean more foam given your short line ( ie straight to tap).

 

[DuncB]

Thanks @doug293cz

Can I give myself a B grade?

 

[doug293cz]

Thanks @doug293cz

Can I give myself a B grade?

Sure.

Brew on

 

[Christoff]

That's an unusual size, what physical dimensions is it? It only looks about 3 inches long in the photo and max one inch wide.
But there is a parallax effect going on.
The nearest to 74g I found on line was an 88g one that was

• Length: 176mm
• Width: 35.2mm
• Neck Length: 24.3mm
• Neck Width: 16mm
• Thread: M16 x 1.5 Not sure this thread would fit the mini regulator normally it's a

also said not food safe and was from hungary.

Found one that is 16g of CO2

Total weight 58gm. Size 88.6mm x 21.9mm


I have noted that you mention it is at 20 psi once half drunk this again changes the criteria on the calculators and would mean more foam given your short line ( ie straight to tap).

It came with the kit from NB (see pic).

I cranked it up to 20 psi after I took it to a friends place and served them flattish beer (about a month, month and a half ago). I figured it may have needed more CO2 but when I had a beer the other day (the beer that prompted this post) same thing, arguably worse. Lots of foam at first (had to wait it out to finish filling the glass) and upon my first or second sip, almost totally flat.

 

[DuncB]

"arguably worse. Lots of foam at first (had to wait it out to finish filling the glass) and upon my first or second sip, almost totally flat."

This confirms your beer has carbonated.

It is overcarbonated for the delivery method you have.

You need a long piece of tubing dictated by the calculators mentioned earlier by @doug293cz and in my workings ( based on 12 and 15 psi ) but for 20 psi and the temperature you are serving at.

 

[Christoff]

"arguably worse. Lots of foam at first (had to wait it out to finish filling the glass) and upon my first or second sip, almost totally flat."

This confirms your beer has carbonated.

It is overcarbonated for the delivery method you have.

You need a long piece of tubing dictated by the calculators mentioned earlier by @doug293cz and in my workings ( based on 12 and 15 psi ) but for 20 psi and the temperature you are serving at.

I reduced the beer from 20 PSI to serve, that was just the pressure I attempted to carbonate at.

Forgive me if this is like beating a dead horse. So if I understand this correctly, I either need to add one of those picnic lines/taps to the keg so there is sufficient line, or I need to change something in the current set up. I bought this mini keg set up for its compact nature and did not read anything online about the tap being an issue connected to the lid. NB does not think this is either. If I understand your post, and others, I have to adjust the temp and psi to work with the current set up. I am just not sure how to adjust the current set up's temp and PSI so I don't have to drink flat beer from it.

 

[ba-brewer]

@Christoff is this same setup that you have?
Complete 1 Gallon Mini Keg System

There is a video for that product showing it pouring correctly, have you reached out to NB to see what they say or how to get a proper pour?

 

[Christoff]

@Christoff is this same setup that you have?
Complete 1 Gallon Mini Keg System

There is a video for that product showing it pouring correctly, have you reached out to NB to see what they say or how to get a proper pour?

I have found NB to be totally useless in getting help. I originally reached out to the after my first unsuccessful carbonation attempt, I followed their instructions to a T, and still had the same thing happen. They eventually told me they have found metal shards get stuck in the gasket(?) and this could contribute to it, but I haven't had a chance to check because there is still beer in there, (hence part of why i think a leak may be contributing to an inability for the CO2 to dissolve into the beer). Upon a second conversation the customer service was terrible. I'd rather have the keg collect dust than deal with them again (I've also had several other issues with the other two orders I have made so I am not impressed).

 

[ba-brewer]

I have found NB to be totally useless in getting help. I originally reached out to the after my first unsuccessful carbonation attempt, I followed their instructions to a T, and still had the same thing happen. They eventually told me they have found metal shards get stuck in the gasket(?) and this could contribute to it, but I haven't had a chance to check because there is still beer in there, (hence part of why i think a leak may be contributing to an inability for the CO2 to dissolve into the beer). Upon a second conversation the customer service was terrible. I'd rather have the keg collect dust than deal with them again (I've also had several other issues with the other two orders I have made so I am not impressed).

I would assume that lid has some sort of flow restriction built in to allow it to work like they show in the product video. As painful as it is to deal with their customer support I would push back on them again for more information on how to get the tap to work or what they were doing to get a decent pour in the video. Tell them you want your money back that might help.

If you questioning if the beer is truly carbonated depressurize the keg, remove the lid and pour some into a glass to see if the beer is carbonated. With the lid off you can inspect the o-rings and the tap to see if there are any issues.

I think I read where people would drop the pressure to serve beer from foamy kegs. Have you tried dropping the pressure?

Might be helpful to have a pressure gauge on a disconnect so you can confirm the pressures being applied to the keg. Maybe the gauge on the regulator is faulty.

 

[Christoff]

If you questioning if the beer is truly carbonated depressurize the keg, remove the lid and pour some into a glass to see if the beer is carbonated. With the lid off you can inspect the o-rings and the tap to see if there are any issues.

That’s a good idea. Not sure why I didn’t think of it.

I think I read where people would drop the pressure to serve beer from foamy kegs. Have you tried dropping the pressure?

Yeah. I drop it to apx 10 psi before serving.

Might be helpful to have a pressure gauge on a disconnect so you can confirm the pressures being applied to the keg. Maybe the gauge on the regulator is faulty.

Another good idea. It’s on a ball lock so maybe I’ll just connect it to my Keezer regulator and see.

NB did make a rather large gesture to offset the inconvenience of the issue. In my irritation I probably should have just had them replace it but I wasn’t giving myself enough credit that I actually had a rough idea of what I was doing. They sent me a ball lock lid so I could at least connect it to my Keezer, but I’d much prefer to use it for the purpose I bought it (mobile beer drinking). I figured it was me to a degree and I’ll eventually figure it out but I’m thinking that may not be the case anymore. Particularly with all the info from this post.

 

[DuncB]

If you had a leak the gas bulb would have emptied over those few weeks.
The pressure would drop on the gauge and read zero over time. Many people lose lb of gas without knowing it when they have a leak.
Your system doesn't sound leaky from your info.
If you have another pressure gauge put that on the gas post, use the PRV to drop pressure to 5 psi.
Wait a while then use PRV again to drop pressure and repeat until pressur doesn't rise above 5 after a vent and wait.
Then reattach regulator set at 5 psi and try a pour, ensuring keg kept in fridge during this process.
You will find that there is less foam and the beer will seem fizzier.

 

[DuncB]

"If you questioning if the beer is truly carbonated depressurize the keg, remove the lid and pour some into a glass to see if the beer is carbonated. "

"That’s a good idea. Not sure why I didn’t think of it."

@Christoff you didn't need to think of it l suggested this in post 17.

If you thought of your minikeg as a large beer bottle and unscrewed the top and poured the beer it would probably pour like a beer out of a bottle and be fine.

 

[Christoff]

"If you questioning if the beer is truly carbonated depressurize the keg, remove the lid and pour some into a glass to see if the beer is carbonated. "

"That’s a good idea. Not sure why I didn’t think of it."

@Christoff you didn't need to think of it l suggested this in post 17.

Ha so you did

 

[Beermeister32]

I got tired of using the mini regulators, I could not get them to stop leaking. I ended up using a standard regulator.

Best performance I’ve had is to naturally carbonate in the keg, then use a large 88-95 gram cartridge to push.

Cartridge lasts, I had one keg over 6 months on one cartridge.

 

[balrog]

Yeah. I drop it to apx 10 psi before serving.

I have a little Ukeg or something. Same idea. 64oz beer, CO2 cartridge, no line length. I carefully decant carbed beer from keg into this, turn it to 10psi to carry to tennis, play (sorta) tennis, ****THEN I TURN THE FVCKER DOWN TO NOTHING PSI*** and serve.

 

[Christoff]

I have a little Ukeg or something. Same idea. 64oz beer, CO2 cartridge, no line length. I carefully decant carbed beer from keg into this, turn it to 10psi to carry to tennis, play (sorta) tennis, ****THEN I TURN THE FVCKER DOWN TO NOTHING PSI*** and serve.

It’s like the Hash. Drinkers with a run of problem (Google it. It’s amazing)

Thanks. I may start just turning it down all together

 

[Christoff]

I got tired of using the mini regulators, I could not get them to stop leaking. I ended up using a standard regulator.

Best performance I’ve had is to naturally carbonate in the keg, then use a large 88-95 gram cartridge to push.

Cartridge lasts, I had one keg over 6 months on one cartridge.

View attachment 809492View attachment 809493

Thanks a lot. Those pics are great. It’s too bad if I have to replace equipment but reading online it sounds like you aren’t the only one with a leaky mini reg