With he evolution of our P.E.T. pressure fermenter range there was also a need to improve the design and function of the spunding devices brewers use to control the pressure held and released in the fermenter tanks and also to control the pressure in their kegs when transferring from fermenter to keg.


When we originally introduced Fermentasaurus to the market in 2016 we only had one style of spunding valve that was manufactured from brass and cobbled together with a gauge using threaded brass connections with plumber’s tape between all the joins. There is a photo attached. This is the original design and utilised a poppet style adjustable valve tip.


The Brass upgrade of the original design was introduced in our NEW Design (photo attached) around the end 2018 beginning 2019. Our improved design was more sanitary and manufactured as one piece rather than multiple pieces. The valve tip was upgraded to have increments in PSI and BAR so that brewers could select the right amount of pressure BEFORE it built up behind the valve inside the fermenter. This was a great step forward.


The cost of manufacture was still pretty steep considering the machining and material costs. Brewers also had to buy a separate gas disconnect with MFL threading to seat the spunding valve onto the gas post of their fermenters. This added between $4 and $12 more to the product price depending on whether the brewer selected a plastic disconnect or a stainless steel variety disconnect.


The price retail was sitting up around $48 to $56 depending on the disconnect variety they selected. It was a high functioning spunding unit when put into action, but easily ruined if brewers managed to put their liquid through them accidentally. This is because the gauge is in the middle of the design and liquid flows past it in the event of an overfill when kegging.

The need to bring that price down and stay competitive was a huge priority for us especially in light of competition.


Spundy, Introduced at the end of 2021 solved more than just the price issue. Far more.


Spundy also solved:

The headspace height issues brewers have in their limited temp controlled fermentation spaces

The need to buy a separate plastic or stainless steel disconnect to attach the valve to the fermenter

The risk associated with blowing liquid through the valve and destroying the function/accuracy of the gauge


Spundy also gave us an opportunity to get a few more features into the design that would allow it to become the most flexible spunding valve out there.


Spundy comes with an adjustable black valve tip but this can be replaced. By utilising PRV’s (pressure relief valves) in the design we were able to build in the ability to set pressure before pressure had built up behind the valve within the fermenter. The PRVs can replace the black valve tip.

The blue and purple PRVs are perfect for setting pressure for 10 or 15psi respectively and are used (blue) ale (purple) Lager.

Moving the valve to the back of the Spundy means that if liquid does blow through it during a keg transfer, the liquid will move to the path of least resistance out of the valve tip. The Spundy is small so it is really simple to clean with hot water and a bit of alcohol to sanitise or sanister spray.


Then there’s the gas harvesting ability of the spundy when fermenting. The Spundy supreme kit comes with some disconnects and line so that the fermentation gas can be utilised to purge and pressurise kegs. Each 5 gallon (19 to 23Litre Batch) produces 200 – 300 litres of CO2. Why waste it.


We’re really pleased with the design and the function of the Spundy. That’s not to say that the older designed brass spunding valves weren’t good. They are.  It’s just that for the flexibility and price, the Spundy is simply better.


Spundy’s little gauge has a higher pressure range that is still really accurate given the size.