Need help with regulators/ co2 tank

[fermentingnewb]

Hey Guys,

Im not super bright when it comes to this so need a little help. I have a 5lb co2 tank that came with a regulator for two kegs. I figured if i purchased a second regulator, I would be able to set the second regulator to different PSI for different kegs. Right now when I set my primary regulator to 20 psi, my second regulator reads 15 psi, and i cannot lower it to 12 or so (what I want) to be able to serve the beer. What i am trying to accomplish is to be able to control different pressure for each keg. One gauge to be at 12 for one keg, one gauge to be 12 for a different keg, another one maybe at 30 to force carb, etc.

 

[day_trippr]

Is that four regulator bank sold as secondary regulators or primaries? (looking at those gauges I'm guessing primaries). If primary, that would be your problem. You need secondary regulators to cascade them behind a primary. They use a much more compliant spring inside the body that lets them operate around 5 psi below whatever pressure is fed them from a primary regulator.

But - otoh - if those are secondary regulators, if you want to lower the output pressure from a higher setting, you need to dial the regulator back, then release the pressure on the output to get the gauge to drop, as higher pressure on the output than what the regulator is set for will literally back-feed to the low pressure gauge until it's released...

Cheers!

 

[Zippy123]

I should know better than to disagree with @day_trippr , but I disagree. The bank of 4 regulators look like secondaries to me.

The information below assumes you are looking at the regulators straight on as in the IMG_0956 pic.

The primary regulator, the one attached to your CO2 tank, has a high-pressure input at 3 o'clock. That's the pressure directly from the tank, and that high pressure runs through the primary regulator to the 9 o'clock position where the high pressure gauge is installed. That high pressure gauge will read 500 PSI until the tank is nearly empty, and the reason for that is beyond this thread. For now just accept that the high pressure gauge will read about 500 PSI until the tank is close to empty. The primary regulator regulates down the high pressure to the range of 0-60 PSI, which is called the "secondary pressure". The secondary pressure is present at 12 o-clock where the secondary gauge is installed (it probably ranges 0-60 PSI) and is also present at 6 o-clock where the Y and the two shutoff valves are located. If you shut off the valve on the tank, then close the secondary valve on the left, then open the secondary valve on the right you'll bleed off the pressure from the secondary part of the regulator. At this point the secondary valve (12 o-clock) should read 0. Now open the tank valve and CO2 will hiss out the secondary port on the right. Quick close the secondary valve on the right because you don't want to waste CO2. The secondary valve will jump up to a number, probably 20 PSI since you said that's where it was set. This means there is 20 PSI of CO2 (secondary pressure, or low pressure) available at those two ports at the Y.

The bank of regulators you have I believe are secondary regulators. This means they take low pressure from the secondary side of the regulator on your tank and allow you to independently regulate down the pressure to each output on the secondary regulator bank. Looking at the bank of secondary regulators, the secondary pressure from the Y at the tank regulator feeds through the bank of regulators, from the 3 o'clock position to the 9 o'clock position. This provides secondary pressure to all of the secondary regulators in the bank. If you put a regulator gauge at the 9 o'clock position on the far left side of the secondary bank it should read the same as the secondary gauge on the tank regulator. Because that should be the same pressure. This is where the fun begins. Each of those regulators on the bank has a gauge at 12 o'clock, a valve/output at 3 6 o'clock, and an adjustment screw in the middle. The adjustment screw allows you to adjust the output of that regulator independent of the other regulators. You should be able to adjust each of the regulators in the bank from 0 PSI to n PSI, where n is the secondary or low pressure from the regulator attached to your tank (shown on the 12 o'clock gauge on the tank regulator).

Be aware that adjusting CO2 pressure with regulators (squishy) is not like adjusting tension with a turnbuckle (firm). It will take some time for adjustments to settle, and there is hysterisis. Let's say you pressurize a keg to 12 PSI for a few weeks then start tapping off beer. The pressure might drop to 10 PSI before the diaphram opens up and equalizes the pressure to 12 PSI. Just like your home heating system where the set point is 68 degrees. The furnace may kick on at 68 and kick off at 70. This is a long way of saying, make small changes to secondary pressures for your kegs or you will overshoot and undershoot your desired settings.

Didn't expect this to be so long, but there it is.

Made some edits edits because I wrote too quckly then read it later. Sorry.

 

[day_trippr]

I think I covered both sides of the question of what those are and why the OP may be seeing what's being seen
It's not obvious that the shut-off valves have integrated anti-backflow "check" valves either, so back pressure will be a thing...

Cheers!

 

[fermentingnewb]

I should know better than to disagree with @day_trippr , but I disagree. The bank of 4 regulators look like secondaries to me.

The information below assumes you are looking at the regulators straight on as in the IMG_0956 pic.

The primary regulator, the one attached to your CO2 tank, has a high-pressure input at 3 o'clock. That's the pressure directly from the tank, and that high pressure runs through the primary regulator to the 9 o'clock position where the high pressure gauge is installed. That high pressure gauge will read 500 PSI until the tank is nearly empty, and the reason for that is beyond this thread. For now just accept that the high pressure gauge will read about 500 PSI until the tank is close to empty. The primary regulator regulates down the high pressure to the range of 0-60 PSI, which is called the "secondary pressure". The secondary pressure is present at 12 o-clock where the secondary gauge is installed (it probably ranges 0-60 PSI) and is also present at 6 o-clock where the Y and the two shutoff valves are located. If you shut off the valve on the tank, then close the secondary valve on the left, then open the secondary valve on the right you'll bleed off the pressure from the secondary part of the regulator. At this point the secondary valve (12 o-clock) should read 0. Now open the tank valve and CO2 will hiss out the secondary port on the right. Quick close the secondary valve on the right because you don't want to waste CO2. The secondary valve will jump up to a number, probably 20 PSI since you said that's where it was set. This means there is 20 PSI of CO2 (secondary pressure, or low pressure) available at those two ports at the Y.

The bank of regulators you have I believe are secondary regulators. This means they take low pressure from the secondary side of the regulator on your tank and allow you to independently regulate down the pressure to each output on the secondary regulator bank. Looking at the bank of secondary regulators, the secondary pressure from the Y at the tank regulator feeds through the bank of regulators, from the 3 o'clock position to the 9 o'clock position. This provides secondary pressure to all of the secondary regulators in the bank. If you put a regulator gauge at the 9 o'clock position on the far left side of the secondary bank it should read the same as the secondary gauge on the tank regulator. Because that should be the same pressure. This is where the fun begins. Each of those regulators on the bank has a gauge at 12 o'clock, a valve/output at 3 6 o'clock, and an adjustment screw in the middle. The adjustment screw allows you to adjust the output of that regulator independent of the other regulators. You should be able to adjust each of the regulators in the bank from 0 PSI to n PSI, where n is the secondary or low pressure from the regulator attached to your tank (shown on the 12 o'clock gauge on the tank regulator).

Be aware that adjusting CO2 pressure with regulators (squishy) is not like adjusting tension with a turnbuckle (firm). It will take some time for adjustments to settle, and there is hysterisis. Let's say you pressurize a keg to 12 PSI for a few weeks then start tapping off beer. The pressure might drop to 10 PSI before the diaphram opens up and equalizes the pressure to 12 PSI. Just like your home heating system where the set point is 68 degrees. The furnace may kick on at 68 and kick off at 70. This is a long way of saying, make small changes to secondary pressures for your kegs or you will overshoot and undershoot your desired settings.

Didn't expect this to be so long, but there it is.

Made some edits edits because I wrote too quckly then read it later. Sorry.

Thank you for the help. Another question for ya. If one of the secondaries is set at 30 for example and one at 12, do I need at least 30 psi coming for the primary maintain the 30/12 for both gauges, or would I need at least 42?

 

[day_trippr]

Thank you for the help. Another question for ya. If one of the secondaries is set at 30 for example and one at 12, do I need at least 30 psi coming for the primary maintain the 30/12 for both gauges, or would I need at least 42?

Generally a secondary reg needs 5 psi input over the desired output pressure, so a bank of secondaries needs a supply pressure 5 psi above the highest desired setting. In your example, you would need to supply 35 psi to the bank of secondaries. But always be careful not to exceed the maximum input pressure, which on Taprite secondaries is around 50 psi, iirc, as an example...

Cheers!

 

[tracer bullet]

Another question for ya. If one of the secondaries is set at 30 for example and one at 12, do I need at least 30 psi coming for the primary maintain the 30/12 for both gauges, or would I need at least 42?

Generically, the regulator at the CO2 tank is set at or above the highest value you'd like downstream, and all the regulators downstream are set the same or lower.

There's more to it though... like if it's flowing, or what Daytrippr's saying, temperature factors perhaps, and so on. So if you actually wanted 30 at one of the kegs I would agree to go more like 35 or 40 at the tank. But it need not be 30 + 12 = 42, it's just something a little higher to give some overhead.

 

[Zippy123]

Generically, ...

There's more to it though...

Yep whether CO2 tap system or rocket launcher, once you learn the basics you realize how many details there are!

 

[fermentingnewb]

Generally a secondary reg needs 5 psi input over the desired output pressure, so a bank of secondaries needs a supply pressure 5 psi above the highest desired setting. In your example, you would need to supply 35 psi to the bank of secondaries. But always be careful not to exceed the maximum input pressure, which on Taprite secondaries is around 50 psi, iirc, as an example...

Cheers!

Thank you for all the help!

 

[Bobby_M]

It appears your primary is only set to 15 psi, and that could be reading a little off plus or minus a few psi. Crank that up higher and you'll have more pressure available at the secondary bank.