Blowtie spunding valve

[RickyLopez]

I can’t get this thing to work- but I’m almost sure I’m not setting it correctly!

So, I pressurized a keg at 15 PSI, connected the blowtie and set it for 15 PSI.

now, when I hook it up to my fermenter, it doesn’t seem to be letting any gas out!!!! The dial went all the way around the gauge!!!! So, it’s not letting gas escape, from what it seems.

help???

 

[Bobby_M]

Was gas escaping when you had it hooked to the keg?

 

[RickyLopez]

Was gas escaping when you had it hooked to the keg?

No, but is it supposed to? Wouldn’t it only release has if the PSI exceeds the set amount?

 

[RickyLopez]

No, but is it supposed to? Wouldn’t it only release has if the PSI exceeds the set amount?

Gas*

 

[McMullan]

How was the spunding valve set to 15 psi? If you connect it to a vessel pressurised to 15psi the guage reads 15psi. If the valve is set for a higher pressure the guage is going to creep up when connected to an FV during fermentation.

 

[Golddiggie]

What does it do when you release the pressure from the Blowtie? When I used them, I never had an issue. Then again I also made sure to have it going into a jar of Starsan so that I could SEE gas escaping. Ensuring that I had it set to the correct level.

 

[DuncB]

Firstly when you had your keg to test from at 15 psi that was a pressure checked with another gauge? Yes I'm assuming.

When you attached your blowtie turn the yellow " key " around clockwise this increases the pressure setting that the blowtie will " blow off " So will be well above your 15 psi.
Then turn back anticlockwise until you get gas coming out of the end of the spunding valve. That is around your set pressure that you want. It will need fine tuning around this, just because it's coming out at 15 psi doesn't necessarily mean that it will stop at 14 psi it might be 10 psi so watch out for this.
If you have a jumper connector you can tune it of a CO2 cylinder with a regulator more accurately. But you'll get there fine tweaking it on a ferment.

PS if you've fitted a non return ball lock like I did once through ignorance to your blowtie no gas will come out at all and you get a very high pressure ferment.

 

[RickyLopez]

How was the spunding valve set to 15 psi? If you connect it to a vessel pressurised to 15psi the guage reads 15psi. If the valve is set for a higher pressure the guage is going to creep up when connected to an FV during fermentation.

Should I twist the knob counter clockwise?
how should I set it initially?

 

[RickyLopez]

Firstly when you had your keg to test from at 15 psi that was a pressure checked with another gauge? Yes I'm assuming.

When you attached your blowtie turn the yellow " key " around clockwise this increases the pressure setting that the blowtie will " blow off " So will be well above your 15 psi.
Then turn back anticlockwise until you get gas coming out of the end of the spunding valve. That is around your set pressure that you want. It will need fine tuning around this, just because it's coming out at 15 psi doesn't necessarily mean that it will stop at 14 psi it might be 10 psi so watch out for this.
If you have a jumper connector you can tune it of a CO2 cylinder with a regulator more accurately. But you'll get there fine tweaking it on a ferment.

PS if you've fitted a non return ball lock like I did once through ignorance to your blowtie no gas will come out at all and you get a very high pressure ferment.

Non return ball lock- I’m using the one that came assembled with my Fermzilla. How should I confirm this?

 

[McMullan]

Yes, counter clockwise to reduce set pressure.

 

[DuncB]

Non return ball lock- I’m using the one that came assembled with my Fermzilla. How should I confirm this?

Looks like they are difficult to get now but they look like this,
https://allthingsfermented.nz/produ...-with-check-valve?_pos=6&_sid=aeca3fcc7&_ss=r
I've got them on all my kegs stops back flow, probably over kill.

When you attached your blowtie turn the yellow " key " around clockwise this increases the pressure setting that the blowtie will " blow off " So will be well above your 15 psi.
Then turn back anticlockwise until you get gas coming out of the end of the spunding valve.

Counter clockwise is a different way of saying anticlockwise. Or lefty loosey righty tighty.

I would screw the yellow key in and out a few times to gentle tightness, just to make sure it's loosened up okay. They have a diaphragm inside the valve which could be a bit stiff or stuck if it's been on the shelf a while.

 

[Bobby_M]

No, but is it supposed to? Wouldn’t it only release has if the PSI exceeds the set amount?

Yes, but you said you set the blowtie for 15psi, which you cannot actually do unless you attach it to something with pressure higher than 15 and turn the knob until it vents DOWN to 15. The knob is the control. The gauge is the confirmation.

Another way to look at it is if the blowtie was set to vent at 20psi via the knob position (and you don't know this yet because you can't know it yet), and you connect it to a keg that has 10psi in it. The gauge will read 10 psi and it will not vent. Ok, so you remove the blowtie and put 5 more psi in the keg and reconnect.

Keg=15 Blowtie reads 15, no vent
Keg=20 Blowtie reads 20, no vent
Keg=25 Blowtie reads 25 initially and then vents down to 20 and stops. ONLY NOW do you know that the blowtie was set to 20. Now you can adjust the blowtie to vent at any pressure below that... you slowly turn the know counterclockwise let it vent and see where it stops. Where it stops is the pressure that the blowtie is "set to".

In summary, you have to put more pressure into the vessel than you actually want it to vent to and slowly sneak up on it with the knob.

 

[DuncB]

or dial it back from the " closed / too tight " position it's currently in.

when I hook it up to my fermenter, it doesn’t seem to be letting any gas out!!!! The dial went all the way around the gauge!!!!

Your blowtie is too tight and needs dialling down ie lefty loosey, anticlockwise / counterclockwise until you hear gas coming out. Then it is spunding and you'll have a rough idea of it's release / working pressure.
They are just the same as a regulator if you turn the knob clockwise the pressure goes up in the circuit and the opposite when turned counter clockwise.

 

[marc1]

Non return ball lock- I’m using the one that came assembled with my Fermzilla. How should I confirm this?

If your gas ball lock has an integrated check valve, then the spunding valve won't be able to work.

 

[Rudeoso]

I had the same issue the first time using mine. Turns out it was assembled wrong at the factory. There is flow direction arrow engraved on the blowtie. That's the direction gas will escape. As soon as I changed mine it worked like a charm.

Sorry for the crappy pictures, the glare wouldn't allow a clear view of the arrow. Hopefully you'll be able to see the direction arrow.

 

[DuncB]

@Rudeoso
Seems and looks assembled correctly from the picture it's a slightly different design to yours.
The gauge was working according to the OP statement " The dial went all the way around the gauge!!!! "
Which just shows the spunding valve is in too tight or is jammed.

 

[Carolina_Matt]

Does the blowtie have some sort of internal check valve to prevent CO2 from going into it the wrong way? Let's say I have it set at 5psi, and the excess CO2 goes to a keg. Once the keg gets to 5psi, everything is balanced. What happens when fermentation creates more CO2? I would think the blowtie would push the excess CO2 into the keg. But on the other hand, once the keg has over 5psi it would try to push the pressure back into the fermentation vessel. Can you put, let's say, 30 psi into the keg but only 5psi in the fermentation vessel?

 

[GilSwillBasementBrews]

You would run the line from the fermenter to the keg. The spunding valve would go on the gas out port of the keg. Once the fermenter pushes enough co2 through your keg to reach the set pressure the excess would be bled off into the room.

 

[DuncB]

@Carolina_Matt
As @GilSwillBasementBrews says heres a picture giving a hint but this is two kegs being purged ( after they have emptied) . If I'm purging kegs the water pressure exerts a fair back pressure but if you get a siphon going the primary fermenter if a PET one will collapse as the liquid siphon is strong. The valve is one way lying underneath the yellow key so unless the valve fails pressure goes normally from ferment to the open air. In the case of higher pressure mentioned beyond the valve then that would be the restricting factor.

 

[Carolina_Matt]

The part I don't understand is how the excess pressure gets bled into the room. When the blowtie is attached to the fermentation vessel and the output is connected to the sealed keg, where does the excess pressure get bled from (assuming the keg is properly sealed and the connections are tight).

 

[McMullan]

The part I don't understand is how the excess pressure gets bled into the room. When the blowtie is attached to the fermentation vessel and the output is connected to the sealed keg, where does the excess pressure get bled from (assuming the keg is properly sealed and the connections are tight).

The spunding valve is attached to the gas post on the keg. You could daisy-chain kegs. The last in the chain gets the spunding valve.

 

[Carolina_Matt]

I'm talking about a setup like this, where the spunding valve is not at the end of the chain. It's at the beginning of the chain, attached to the fermentation vessel. From there it goes to a sealed keg. Once the keg has the same psi as the valve is set to, what happens when more CO2 is created?

 

[marc1]

I'm talking about a setup like this, where the spunding valve is not at the end of the chain. It's at the beginning of the chain, attached to the fermentation vessel. From there it goes to a sealed keg. Once the keg has the same psi as the valve is set to, what happens when more CO2 is created?

I think the valve would not be able to vent if the downstream pressure is higher than the keg pressure, so you would end up with high pressure in both the fermenter and the keg.

I don't recommend using it that way.

 

[McMullan]

I'm talking about a setup like this, where the spunding valve is not at the end of the chain. It's at the beginning of the chain, attached to the fermentation vessel. From there it goes to a sealed keg. Once the keg has the same psi as the valve is set to, what happens when more CO2 is created?

Well, assuming the PRV on the keg works in time, hopefully things won't go 'bang'. You have a closed system making the spunding valve redundant.

 

[szap]

The spunding valve is attached to the gas post on the keg. You could daisy-chain kegs. The last in the chain gets the spunding valve.

View attachment 764474

I guess I don't understand what the OP is trying to accomplish. The blowtie is designed to allow a pressure fermentation. This is how mine is setup and works fine.

 

[cfrazier77]

All Lagers were cold lagered, even before artificial refrigeration. They used a combination of naturally cold cellars and natural ice.

I'm talking about a setup like this, where the spunding valve is not at the end of the chain. It's at the beginning of the chain, attached to the fermentation vessel. From there it goes to a sealed keg. Once the keg has the same psi as the valve is set to, what happens when more CO2 is created?

Put a disconnect on the other post of that keg to prevent backpressure.

 

[doogie]

I use the output to purge my keg. Just add an airlock.

 

[Bobby_M]

I'm talking about a setup like this, where the spunding valve is not at the end of the chain. It's at the beginning of the chain, attached to the fermentation vessel. From there it goes to a sealed keg. Once the keg has the same psi as the valve is set to, what happens when more CO2 is created?

I don't understand what's happening in that picture. I suspect the intention was to CO2 purge the keg through the "spare" CO2 from the fermenter but the part that is missing is the vent on the keg. That would either be a gas QD with a hose going into a bucket of starsan or better yet, just run the blowtie directly on the keg gas post instead of on the fermenter.

 

[DuncB]

@Bobby_M
I agree not sure why you would set it up as that photo, what is the OP trying to achieve?

Just regard the purging kegs as headspace and the spunding valve goes on the end of the chain and vents to the air. There is no need to set it up as @doogie
just use a pipe with gas connector one end and liquid connector on the other.
So gas out of fermenter to liquid in of keg being purged ( of air ) and then spunding valve on the gas post.
Or gas to gas and liquid connector to collecting vessel if you are pushing starsan out. Then when empty use the gas to liquid connector and spund on the gas post of the keg.

 

[Carolina_Matt]

@Bobby_M
I agree not sure why you would set it up as that photo, what is the OP trying to achieve?

Just regard the purging kegs as headspace and the spunding valve goes on the end of the chain and vents to the air. There is no need to set it up as @doogie
just use a pipe with gas connector one end and liquid connector on the other.
So gas out of fermenter to liquid in of keg being purged ( of air ) and then spunding valve on the gas post.
Or gas to gas and liquid connector to collecting vessel if you are pushing starsan out. Then when empty use the gas to liquid connector and spund on the gas post of the keg.

To be clear, I've never actually set it up that way (other than for a few seconds to take the picture). I do it like you mentioned. Gas to Gas to push out the starsan. Then gas to liquid to fill up the keg with co2, with the spunding valve on the keg's gas post.

My question was theoretical - what would happen if it was set up that way. The spunding valve is meant to push out any excess co2, but if it's going to a sealed keg then the keg will eventually try to push the excess co2 back into the fermentation vessel. It sounds like the spunding valve wouldn't be able to release the excess pressure so it would build up in both the keg and the FV.