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The Sspunding Valve from Ss Brewtech allows you dial in the precise pressure at which you want your Unitank fermenting. A spunding valve is essentially an adjustable pressure relief valve. Normal PRVs that are found on kegs, couplers and come stock on Ss Unitanks, operate as safety features that will release pressure when it’s nearing dangerous levels. Spunding valves, on the other hand, allow you to set the release pressure much lower. Simply dial in your desired fermentation pressure, and the Sspunding valve will release excess pressure when it gets too high.

The scaled Sspunding valve includes an etched sleeve with a scale between 0-2 BAR, along with a pressure calibrated spring. This version is perfect for a home or nano brewer that wants to be able to dial in pressures on the fly without having to match the release pressure using a gauge. The scaled version also features a pressure release knob to quickly and easily verify or equalize tank pressure. If you’re looking for a more affordable option, check out FE892A for the non-scaled version.

The polycarbonate cup is designed to hold sanitizer so that the tank remains 100% sanitary throughout the course of the fermentation process.

You can pair the spunding valve with a 1.5″ tri-clamp tee (H666) and 90-degree elbow (H667), which enables the unit to be installed on the Unitank’s blow off arm, as shown in the photo.

All 304 Stainless Construction
Only for use with pressure rated Unitanks
1.5″ TC interface
Removable sanitizer cup
Easy disassembly for cleaning
Not for use on low pressure vessels (Chronicals, etc.)

For Your Safety: Always leave the fixed-pressure PRV included with the Unitank in place. Never exceed the maximum rated working pressure of the vessel at any time during operation.

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.