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The BlowTie Spunding Valve is used to release excess pressure on a pressurized fermenter or from a keg while doing pressure transfers. Thanks to the large surface area of the diaphragm, this style spunding valve is much more accurate than the poppet style. 8 mm Duotight fittings at both inlet and outlet make this unit perfect for use with EVABarrier 8 mm OD tubing. The blow off pressure can be set by either pairing the BlowTie with the included Push-In Pressure Gauge, or by attaching it to an empty keg that has been pressurized to the desired psi.

Made from food grade acetal
Stainless screws
Easily disassembles for cleaning
8mm (5/16″) Duotight fittings at both ends
0-40 psi pressure rating
Two functions in one great piece of hardware!

The Ball Lock QD Adjustable Pressure Valve W/Gauge can also be used to relieve pressure while filtering from one keg to another. At the same time it gives you the ability to read the pressure in the receiving keg. And Ferment under desired pressure!

1. Pressurized fermentation.  Ferment in a 5 or 10 gallon corny keg and use your Spunding Valve instead of an airlock.  This allows you to ferment at your desired pressure.
2. Dry hop under pressure.  This allows you to dry hop earlier while reducing oxygenation.  Active yeast are more likely to metabolize oxygen that’s introduced during dry hopping during active fermentation.  Since CO2 is not exiting beer as vigorously under pressure, wanted compounds, flavors and aromas are more likely to stay in your beer under pressure.
3. Naturally and accurately carbonate beer right in the keg.
4. An airlock replacement.  Keep the valve wide open for non-pressurized fermentations.  Only do this if you have plenty of head space.  This wouldn’t make a great blow off tube.
5. Keg to keg transfers.  Use the Spunding Valve to allow excess gas to exit the receiving keg as you transfer under pressure.  Helps you achieve a slow, controlled and pressurized transfer.
6. Fix over-carbonated beers.  Use the same general process as for carbonation (skipping the addition of fermentable sugar).  Use a carbonation chart to determine proper pressure for the temperature the keg is at.  The Spunding Valve allows excess pressure to vent until the new carbonation level is achieved.  You can agitate the keg to fix carbonation more quickly.
7. Test for keg leaks.  Pressurize your keg to serving pressure.  Put the Spunding Valve on (with the pressure set well above your serving PSI) and note the reading.  The gauge should remain steady.  If pressure drops, you know you have a keg leak.  It’s worth noting that this checks the entire keg including gas body o-ring.  That spot is hard to check and other way as it’s only in function when the gas QD is on.  When the gas QD is on… it’s difficult to spray and check for bubbles underneath the gas QD.  Thanks to Scott Janish for this tip!
8. As an airlock for long term aging of beers.  Airlocks can run dry over time.  A Spunding Valve will not.