Spike Gas Manifold Safety Warning

[CodeSection]

I just received this via email...

Dear Brewmasters,

Thank you for your past purchase of a Spike gas manifold, we certainly appreciate your business!

We’ve recently noticed some customers commenting and using the gas manifold as a spunding valve during pressure fermenting. A spunding valve is used to release pressure at a pre-designated pressure level, set by the brewer. The Spike gas manifold, however, was not engineered to be used in the same fashion as a spunding valve. Instead, it was engineered to be a safety pressure release during forced carbonation and pressure transfers.

Using the Spike gas manifold to pressure ferment during primary fermentation can lead to unsafe conditions. When we refer to pressure fermentation we mean adding wort to your conical, pitching yeast, and then sealing off the fermenter with the Spike gas manifold instead of a pressure blow-off (e.g., an airlock, a blow-off tube, etc.). During primary fermentation, the krausen can slowly rise filling the lid head space. If the Spike gas manifold is used instead of a pressure blow-off, the krausen can fill the gas manifold and clog the safety pressure release valve. With the safety pressure release valve clogged and the fermentation reaction creating additional pressure with nowhere to go, eventually a failure can occur that can result in a substantial mess, and potentially an injury.

For these reasons, we do not recommend that you use the Spike gas manifold to ferment under pressure (i.e. during primary fermentation). We at Spike are continuing to investigate reliable and safe options for pressure fermentation. When we identify such an option, we will let you know.

If you have any questions, please reach out to our service team at [email protected]

Thanks,
Team Spike

 

[day_trippr]

Someone done got blown up

 

[eric19312]

Wait I thought fermenting under pressure was unitank feature. Part of why I bought mine...


https://www.morebeer.com/category/fermenting-pressure.html

https://www.ssbrewtech.com/products/sspunding-valve

https://spikebrewing.com/blogs/ask-a-pro/pressurized-fermentation

 

[mongoose33]

Well, shoot. That was one of the reasons I bought the Spike, so I could essentially do spunding.

I'm going to have to think about this. I don't let the PRV act as a spunding valve, I wait until there's about 7 or so points of gravity remaining and then seal up the fermenter.

One thing I may look into is using my 1.5" sight glass under the PRV so I could see if the krausen is approaching the top. I mostly do 5-gallon brews in my CF10 so I think this is a non-issue in those cases, but with a vigorous fermentation and a too-full fermenter, I can see how the krausen would invade the pressure manifold.

I suppose, too, that I could just have a blowoff barb or cane on there and when I get to the 7 points or so of gravity remaining, simply quickly swap the blowoff barb for the pressure manifold. It would admit almost no air to do that, and with the fermentation still ongoing, that oxygen should be used up.

Thoughts on all this?

 

[CodeSection]

Wait I thought fermenting under pressure was unitank feature. Part of why I bought mine...


https://www.morebeer.com/category/fermenting-pressure.html

https://www.ssbrewtech.com/products/sspunding-valve

https://spikebrewing.com/blogs/ask-a-pro/pressurized-fermentation

I think in Spike's case, at least how I understand it, they are talking about:

1. Using a blowoff tube or cane for primary fermentation to avoid clogging up their PRV. Then attach the PRV to the lid or to your blowoff cane when carbonating or doing a closed transfer; and
2. Their PRV is not a spunding valve. They did not say you could not attach a spunding valve to the PRV. In that case, the PRV is still intact for primary safety....

In the SSB link:
"Lastly, a final note on safety, always leave the fixed-pressure PRV included with the Unitank in place, never exceed the maximum rated working pressure of the vessel at anytime during operation."

At the bottom of your Spike link:
"In summary
Brewing science in this arena is not well documented. To encourage a healthy and complete fermentation, the traditional blow off method remains the gold standard among professionals. Proceed at your own risk!"

I'm surprised MoreBeer does not have a warning disclaimer...

 

[Blazinlow86]

Not to be a smartass but this all seems pretty common sense. The vessel is designed to follow a typical professional process. As far as I'm aware spunding is more a homebrew cheat to save money on co2 and isn't typically done at the professional level. Using the carb stone to carbonate is quick,easy and precise. Use the blowoff for the first few days and then switch over the pressure manifold once the fermentation slows down. Cold crash and add the stone and your done the next day. It's not a spike brand issue and would be the same for any vessel not rated for 30+psi. I appreciate everyone has there own way of doing things but if spunding is something your interested in a Corny keg is a better option. Cheers

 

[gman1974]

I got the same e-mail today. Interesting since I'm quite certain Spike marketed this product to be able to ferment under pressure. I'm also quite sure they were there prior, but all references to fermenting under pressure have been scrubbed from their webpage.

This particular part of their communication is what raises my eyebrow and leads me to believe this is CYA for possible litigation purposes.
"When we refer to pressure fermentation we mean adding wort to your conical, pitching yeast, and then sealing off the fermenter with the Spike gas manifold instead of a pressure blow-off (e.g., an airlock, a blow-off tube, etc.)."

I call BS on this and not at all the bill of goods we were sold prior. I would hope their would be more transparency here on this and that Spike do right by their customers.

 

[Tom R]

Aren't they just saying that if you're going to spund in their unitanks, use a spunding valve designed for the purpose, not their PRV manifold?

Seems reasonable to me.

 

[gman1974]

Aren't they just saying that if you're going to spund in their unitanks, use a spunding valve designed for the purpose, not their PRV manifold?

Seems reasonable to me.

"For these reasons, we do not recommend that you use the Spike gas manifold to ferment under pressure" I don't believe that is what they are saying Tom. I hope they do come up with a safe alternative. If this were not the case, I would have opted for the competitors product instead.

 

[Blazinlow86]

"For these reasons, we do not recommend that you use the Spike gas manifold to ferment under pressure" I don't believe that is what they are saying Tom. I hope they do come up with a safe alternative. If this were not the case, I would have opted for the competitors product instead.

But what competitors product offer that?

 

[Tom R]

Perhaps that is their intended meaning.
If I were Spike and wanted to convey that meaning I would state "We do not recommend fermenting under pressure in this product".

I tend to take things literally, and sometimes that is a problem.

 

[gman1974]

But what competitors product offer that?

SSbrewtech does. Their unitanks are marketed for fermentation under pressure.

 

[eric19312]

SSbrewtech does. Their unitanks are marketed for fermentation under pressure.

I thought Spikes were marketed for fermenting under pressure too. That certainly didn’t appear to be a differentiating factor when I was choosing between the two. I think Spike lawyered up, probably getting ready to sell out.

 

[Blazinlow86]

SSbrewtech does. Their unitanks are marketed for fermentation under pressure.

Ss unitanks have a 18 psi working pressure vs 15psi on the spike. That's no were near enough to handle sealing the fermentor during primary either. It would just allow for a bigger bang. cheers

 

[eric19312]

Ss unitanks have a 18 psi working pressure vs 15psi on the spike. That's no were near enough to handle sealing the fermentor during primary either. It would just allow for a bigger bang. cheers

According to SSBrewtech website 15 PSI operating pressure

https://www.ssbrewtech.com/products/half-bbl-unitank

 

[Blazinlow86]

According to SSBrewtech website 15 PSI operating pressure

https://www.ssbrewtech.com/products/half-bbl-unitank

Ah there lowering it then. It started at 30 max psi and then was changed to 18psi operating pressure at some point. I imagine a few people have filled there cf to the brim while having it sealed up and the PVR got gummed up causing the lid to blow off as it would on any other conical on the market homebrew or pro. You can still ferment under pressure with the correct amount of headspace but spike cant recommend it anymore probably for liability reasons. Cheers

 

[Bobby_M]

I don't want to speak for Spike but the issue is that the PRV passageways are small and could clog easily if you're pushing the capacity, with an aggressive overpitch, at a higher temperature, etc, etc. Will it absolutely clog at the first glop of krausen? Probably not but it just takes one fermenter to go boom to scare the crap out of the user but never so much as a corporation trying to survive in ever so litigious times..

 

[Vale71]

"For these reasons, we do not recommend that you use the Spike gas manifold to ferment under pressure" I don't believe that is what they are saying Tom. I hope they do come up with a safe alternative. If this were not the case, I would have opted for the competitors product instead.

English is not my first language but when they write "we do not recommend that you use the Spike gas manifold" how I understand it is that they do not recommend using this particular accessories to ferment under pressure, not that they do not recommend doing pressure fermentation with their Unitank at all.
There are PRVs and spunding valves that can be fitted to any fermenter with standard TC attachments, it's just annoying that Spike is not selling them and one would have to procure them from a third party but it's not the end of the world.

 

[Vale71]

As far as I'm aware spunding is more a homebrew cheat to save money on co2 and isn't typically done at the professional level.

You couldn't have gotten that more wrong if you had tried. Spunding is a typical commercial level process (and has been for hundreds of years BTW) it's homebrewers that have only recently started doing it thanks to the availability of pressure-rated fermentation vessels at typical homebrew scale.

 

[Blazinlow86]

You couldn't have gotten that more wrong if you had tried. Spunding is a typical commercial level process (and has been for hundreds of years BTW) it's homebrewers that have only recently started doing it thanks to the availability of pressure-rated fermentation vessels at typical homebrew scale.

There sealing there conicals from day one and fermenting under 15 psi as mentioned in post #1? Any specific examples of the ones doing that? You couldn't have got that more wrong if you tried at least in my area. The commercial guys here still start off with a blowoff in a bucket typically and only seal it with a spunding valve near the end. Ive always done the same since day 1 for same reasons spike mentioned. I did use the spunding valve set at 2 psi from day one once when I couldn't find my blowoff hose but that was a 12 gallon batch in my cf15 so I wasn't to concerned about the headspace issue. Cheers

 

[SpikeBrewing]

We saw this post pop up and wanted to chime in and answer any questions you all might have.

Over the last few months we've seen a lot of people talking about spunding and pressure fermentation. We've seen some cringe-worthy pictures of different setups and wanted to send out a message as a word of warning.
-We've seen a couple pictures with valves placed before the PRV. If this valve is closed during fermentation then the PRV is rendered useless and the tank no longer has any pressure release.
-We've also seen the manifold placed at the bottom of the TC racking arm. If the krausen goes into the blow off it can get into the manifold and clog the PRV.
-We've had people ask if they can just pitch yeast and cap the blow off port. This is essentially creating a bomb; DON'T DO THIS.

We've just seen too many people that have read an article or thread about spunding or pressure fermenting without understanding the dangers or how to safely do it.

Again we always have customers safety top of mind. We wanted to send out a cautionary message so people can double check their setups and don't ruin any expensive equipment or worse hurt themselves. Remember pressure is extremely dangerous. Pressure fermenting has elevated risks as if the PRV clogs you now have a reaction occuring in the tank that is generating more pressure with nowhere to go. We typically do not advise pressure fermenting due to these risks and because we've seen too many new brewers trying this method out without a proper setup. If pressure fermenting is something you'd still like to try we recommend purchasing a spunding valve while also using our pressure release valve. This word of warning goes for all equipment and not just ours. Please be safe when dealing with pressure!!

 

[Vale71]

Hear, hear.

With safety there is no compromising, ever.

 

[Vale71]

There sealing there conicals from day one and fermenting under 15 psi as mentioned in post #1? Any specific examples of the ones doing that? You couldn't have got that more wrong if you tried at least in my area. The commercial guys here still start off with a blowoff in a bucket typically and only seal it with a spunding valve near the end. Ive always done the same since day 1 for same reasons spike mentioned. I did use the spunding valve set at 2 psi from day one once when I couldn't find my blowoff hose but that was a 12 gallon batch in my cf15 so I wasn't to concerned about the headspace issue. Cheers

You mentioned spunding, if you meant pressure fermentation you should have said that instead.
And yes, pressure fermentation started off in commercial brewing as a way to brew lagers even cheaper, by shaving off as much as 3 days for primary and several weeks for conditioning.

Here is a list of a few breweries doing it:

Heineken
Augustiner
Hofbräu
Paulaner
Spaten
DAB

and the list goes on and on.

Pretty much every brewery that does lagers in the >200 hectos class does it with hardly any eception, it's no longer economically viable otherwise.

 

[Blazinlow86]

You mentioned spunding, if you meant pressure fermentation you should have said that instead.
And yes, pressure fermentation started off in commercial brewing as a way to brew lagers even cheaper, by shaving off as much as 3 days for primary and several weeks for conditioning.

Here is a list of a few breweries doing it:

Heineken
Augustiner
Hofbräu
Paulaner
Spaten
DAB

and the list goes on and on.

Pretty much every brewery that does lagers in the >200 hectos class does it with hardly any eception, it's no longer economically viable otherwise.

Semantics aside and to stay on topic you would agree that commercial brewers aren't sealing there conicals from day one with a 15 psi setting in order to naturally carbonate there beer like some homebrewers have started to do and therefore causing spike to make the statement? Cheers

 

[Vale71]

Semantics aside and to stay on topic you would agree that commercial brewers aren't sealing there conicals from day one with a 15 psi setting in order to naturally carbonate there beer like some homebrewers have started to do and therefore causing spike to make the statement? Cheers

It's not semantics as they're two completely different processes but if it suits you to see it that way...

You are right, commercial breweries (those still responsible for 90% of the world's production) actually seal their fermenters from day 0 (i.e. as soon as they are full) and let the pressure rise all the way to 3 bar following a pre-determined profile involving temperature and pressure. The goal of this is not and has never been natural carbonation, anybody who does this for this very reason really has no idea about what they're doing.

 

[Jag75]

You mentioned spunding, if you meant pressure fermentation you should have said that instead.
And yes, pressure fermentation started off in commercial brewing as a way to brew lagers even cheaper, by shaving off as much as 3 days for primary and several weeks for conditioning.

Here is a list of a few breweries doing it:

Heineken
Augustiner
Hofbräu
Paulaner
Spaten
DAB

and the list goes on and on.

Pretty much every brewery that does lagers in the >200 hectos class does it with hardly any eception, it's no longer economically viable otherwise.

Any reputable brewers lol

 

[Blazinlow86]

It's not semantics as they're two completely different processes but if it suits you to see it that way...

You are right, commercial breweries (those still responsible for 90% of the world's production) actually seal their fermenters from day 0 (i.e. as soon as they are full) and let the pressure rise all the way to 3 bar following a pre-determined profile involving temperature and pressure. The goal of this is not and has never been natural carbonation, anybody who does this for this very reason really has no idea about what they're doing.

Whats the official line in the sand of when fermenting under pressure becomes spunding as there the same process just done at different times. my point is that at least were i live i can go to the 150+ craft breweries and non will be sealing there conicals from day one using a 15 psi prv to ferment under pressure/spund whatever you want to call it. Because in my area we only have a few macro breweries even if they are sealing there conicals from day one using a 15 psi prv to ferment under pressure/spund as this thread is based on there still the minority. its probably 150 to 10. anyway no need to debate this one anymore. its getting off topic now

 

[eric19312]

we recommend purchasing a spunding valve while also using our pressure release valve.

Thanks for the clarification @SpikeBrewing makes sense and certainly don't want to see my fantastic new CF15 either get damaged or worse.

I am not sure I understand how adding the spunding valve helps the situation, at least it it is mounted on the manifold ball lock gas post. Krausen the reaches the PRV would reach the spunding valve pretty much same time and would seem like the spunding valve would clog even easier than the PRV.

 

[SpikeBrewing]

Thanks for the clarification @SpikeBrewing makes sense and certainly don't want to see my fantastic new CF15 either get damaged or worse.

I am not sure I understand how adding the spunding valve helps the situation, at least it it is mounted on the manifold ball lock gas post. Krausen the reaches the PRV would reach the spunding valve pretty much same time and would seem like the spunding valve would clog even easier than the PRV.

A spunding valve has an ID of 1"+. There is more force pushing up on the PRV with the larger diameter and the krausen can actually bubble through the larger openings rather than clogging. Even with a spunding valve we recommend using our PRV as it is designed to pop at 15psi. We would not recommend a Blichmann spunding valve as it has the same potential for clogging. We'd recommend a pro style similar to the ones SS and Stout offer. The key is the larger ID opening.

 

[Blazinlow86]

Any reputable brewers lol

Ouch did craft brewers kick your dog or something? What made you feel only macro breweries are reputable? we have lots of excellent smaller breweries making beers other than mass produced lagers that are very reputable. cheers

 

[Jag75]

Ouch did craft brewers kick your dog or something? What made you feel only macro breweries are reputable? we have lots of excellent smaller breweries making beers other than mass produced lagers that are very reputable. cheers

I was kidding man

 

[Blazinlow86]

I was kidding man

Aha damn Internet. It can be hard to tell sometimes. As majority of Craft breweries use a blowoff setup and typically aren't makings macro style lagers like the examples posted I thought you were taking a jab at them. Cheers

 

[chpueblo22]

A spunding valve has an ID of 1"+. There is more force pushing up on the PRV with the larger diameter and the krausen can actually bubble through the larger openings rather than clogging. Even with a spunding valve we recommend using our PRV as it is designed to pop at 15psi. We would not recommend a Blichmann spunding valve as it has the same potential for clogging. We'd recommend a pro style similar to the ones SS and Stout offer. The key is the larger ID opening.

Looking at building my own manifold for spunding, pressure fermentation, transfers for my new CF10s and had a couple questions.

1) Is this the type of spunding valve you are referring to in the first picture?
2) Is there a downside to using the type of PRV I show in the second picture? It notes having a vacuum break which I imagine would work by letting air in. Assuming I keep pressure while cold crashing though, I'm not sure this would matter or is it better to get a prv without vacuum break?

Currently planning to use a 4 way 1.5" TC cross from top port with prv, ball lock disconnect, and this elbow spunding valve with pressure gauge on third port. A little overkill but I think that would check all the things I could possibly want to do.

 

[Vale71]

1) Is this the type of spunding valve you are referring to in the first picture?

That is a pro-grade a spunding valve and it's pefectly suited. You can get one without the manometer if your tank already has one.

2) Is there a downside to using the type of PRV I show in the second picture? It notes having a vacuum break which I imagine would work by letting air in. Assuming I keep pressure while cold crashing though, I'm not sure this would matter or is it better to get a prv without vacuum break?

Having a vacuum break is not essential but it's definitely a plus and won't hurt your tank's performance in any way.

Currently planning to use a 4 way 1.5" TC cross from top port with prv, ball lock disconnect, and this elbow spunding valve with pressure gauge on third port. A little overkill but I think that would check all the things I could possibly want to do.

You clearly haven't seen my fermenter. I got so much stuff attached at the top I'm afraid one day it's going to fall over from the sheer weight of the accesories...

 

[Brooothru]

That is a pro-grade a spunding valve and it's pefectly suited. You can get one without the manometer if your tank already has one.


Having a vacuum break is not essential but it's definitely a plus and won't hurt your tank's performance in any way.

You clearly haven't seen my fermenter. I got so much stuff attached at the top I'm afraid one day it's going to fall over from the sheer weight of the accesories...

My only question would be 'where' on the fermenter is the spunding valve mounted in Pic #1? I have a nearly identical spunding valve to the one pictured. The connection fitting comes off a T that comes off the top mounted blow-off pipe. Upstream of the spunding valve on the blow-off is a diaphragm pressure gauge, and since the bottom is a frangible seal it cannot be clogged by krausen and will always give an accurate internal pressure reading of the fermenter. Downstream of the spunding valve is a ball valve shut-off and discharge line into a sanitizer-filled jar.

So the setup is: top-mounted blow-off pipe, "T" junction to pressure gauge, "T" junction to spunding valve, ball valve shut-off, discharge bucket. I always have 3" TC mounted PRV with vacuum break at the top of the tank identical to the one in Pic #2, and it's attached whenever any fermentation is going on regardless of pressurized or unpressurized. I'm reasonably confident that this affords me a comfortable and acceptable level of safety with independent redundant sources of backup. I ferment unpressurized until ~5 points of predicted Final Gravity, then close the ball valve on the blow-off pipe and set the spunding valve to 1 bar ~ 14.7 psig. I get carbonated beer that conditions at least a week sooner that's already at serving temperature when it gets pressure transferred to a purged serving keg.

With all that said, something I've noted in the discussion on this thread is the conflating of spunding with pressurized fermentation, which as you pointed out are two different (yet similar) processes. Even though spunding involves pressurization, I think it is best thought of as completing fermentation under partial pressure. As you also pointed out, macro brewers pressure ferment lagers at up to 3 bar with a specific temperature profile that varies as the fermentation progresses to control (speed up) the time to completion of fermentation as well as shape the ester production of the fermentation. Those temperature/pressure profiles are also most certainly tied to specific yeast strains, so one size doesn't necessarily fit all. True, pressurized fermentation does carbonate the beer, but it isn't the same thing as spunding. Or more accurately, spunding is not technically the same thing as pressurized fermentation, which is an expansion of the spunding process.

One other item that has been overlooked in this thread is that fermentation under pressure tends to suppress the formation of krausen in the fermenter. But this factor can also create risk. At a low pressure, say 3~5 psi, a home brewer might think they are "safe" because krausen is suppressed, therefore no worry of a blocked spunding valve. Suppress does not mean eliminate, and the amount of suppression varies with pressurization. The amount of suppression at 14.7 psig is much greater than 3~5 psig. Three to 5 psig fermentation "under pressure" probably presents a significantly larger possibility of a clogged blow-off pipe or spunding valve, especially if the spund is set too soon during fermentation.

In any event, safety and precaution should always take precedence when dealing with pressurized fluids. In the 'good old days' of home brewing, everybody used plastic buckets and glass carboys with rubber stoppers held in place with the tenuous bond of friction. An over-pressure due to a blocked airlock or over-aggressive primary fermentation was solved when the airlock popped out or the top seal of the bucket worked loose and krausen slopped onto the floor or counter top. It made a mess, but in the end it wasn't a big deal. Now with the advent of stainless steel vessels capable of holding significantly higher pressure, we have a two-edged sword that on the one hand allows us to do things in brewing that only professionals could do a few years before, but on the other hand can create very real hidden dangers that may not be obvious to the amateur brewer who is not familiar with the risks associated with high pressure fluids.

Whatever motivated Spike to issue their warning to users shouldn't be the bottom line issue. What's important and mandatory is that end users, especially home brewers, are made aware of the inherent risks and not blindly making modifications to their gear (or using the gear improperly) which could result in a hazardous and potentially deadly situation. I salute Spike's action.

Brooo Brother

 

[chpueblo22]

My only question would be 'where' on the fermenter is the spunding valve mounted in Pic #1? I have a nearly identical spunding valve to the one pictured. The connection fitting comes off a T that comes off the top mounted blow-off pipe. Upstream of the spunding valve on the blow-off is a diaphragm pressure gauge, and since the bottom is a frangible seal it cannot be clogged by krausen and will always give an accurate internal pressure reading of the fermenter. Downstream of the spunding valve is a ball valve shut-off and discharge line into a sanitizer-filled jar.

Brooo Brother

Thanks for the detailed reply. Attached photo is the set up I was thinking. Would allow me to use blow off tube for majority of fermentation and like you mentioned, shut it off during final portions to build up some pressure. My primary goal is to minimize cold side oxidation and I like the idea of being able to use spunding valve (or to force carbonate for pressure transfer) without having to take anything off (i.e. switching from blow off tube to gas manifold). Less interested with pressure fermentation although I am looking to do a lot of lagering so I wouldn't rule it out.

This set-up seem reasonable? overkill? any ways you can see to minimize bulk and accomplish same goals? It seems like only way using a spike unitank given they only have one 1.5" TC port on top.

 

[Brooothru]

From your sketch it looks like you'd have all the bases pretty much covered. I didn't quite understand how you had planned to used the spund/PRV piece in your original post, but now I see you plan a top mount on a 4-way "T" manifold mounted on top of the fermenter. I'm assuming 1.5" TC pipe flange fitting, so probably 1" ID tubing. That, plus the top mounting should mitigate concerns over krausen clogging the works, and having a pressure gauge and a dedicated 'industrial strength' PRV gives you the ability to monitor any dangerous pressure buildup while having a dedicated safety relief.

The one thing I would suggest is to make sure the valve on your blow-off line is a large bore butterfly valve and not a ball valve. It's a bit more expensive, but the lowest 'choke point' on your design (where rising krausen might possibly collect) is right there. A ¾" diameter bore butterfly valve instead of a smaller bore ball valve would mitigate that possibility, as would a domed lid if that's a possible retrofit (not sure what brand/model fermenter you have).

You could also possibly streamline the design by having a 2-way "T" mounted on the top of the fermenter with one side attached to the dedicated PRV and the second side attaching to a manifold that clamps to the side of the fermenter. That manifold would be your blow-off cane and have additional "T" connections for both a side mounted pressure gauge and spunding valve, and end with a ball or butterfly valve so you can either pressurize the tank or vent into a blow-off bucket. This configuration would take a lot of hardware off the top of the fermenter and make it more vertically stable.

The bottom line safety concern is to make sure you have a dedicated PRV mounted high enough on the fermenter to be unaffected by rising krausen, connected with a large enough diameter pipe that krausen won't someday block it (pipe and/or PRV). Even more important is NEVER having any valve or shutoff device placed between the PRV and the inside of the tank. Mr. Murphy and his Laws dictate that sooner or later someone will mis-position that valve at the worst possible time and bad things could/might/will certainly happen. Don't allow yourself to ever be that person.

Brooo Brother

 

[balrog]

I wonder; somehow related? ...
https://www.homebrewtalk.com/forum/threads/how-much-pressure-can-fermentation-build-up.675384/

 

[Brooothru]

Thanks for the detailed reply. Attached photo is the set up I was thinking. Would allow me to use blow off tube for majority of fermentation and like you mentioned, shut it off during final portions to build up some pressure. My primary goal is to minimize cold side oxidation and I like the idea of being able to use spunding valve (or to force carbonate for pressure transfer) without having to take anything off (i.e. switching from blow off tube to gas manifold). Less interested with pressure fermentation although I am looking to do a lot of lagering so I wouldn't rule it out.

This set-up seem reasonable? overkill? any ways you can see to minimize bulk and accomplish same goals? It seems like only way using a spike unitank given they only have one 1.5" TC port on top.

After re-reading your posts I see that you have a Spike CF-10 which is a unitank with a semi-domed top. IIRC, Spike offers a sight glass type lid for some of its tanks (maybe the 4" top TC?). I'm guessing if you bought the unitank with the notion to brew lagers you probably got cooling coils for that 4" TC, but if not that would be a great place to attach your 4-way "T" manifold rather than the 1.5" TC on the periphery of the lid. On the 1.5" mounting, I'd probably go with a 2-way "T" manifold with PRV, and vertically build the other accessories "down the side" if you have or are considering a chilling coil for the 4" TC. There would just be too much stuff on top with glycol lines and a 4-way manifold with all the attachments.

I lucked out with my SS Brew Tech unitank since it has a 8" TC mounted cooling coil with an integrated 3" TC reducer in the middle of the cap that holds a dedicated PRV. My manifold with pressure gauge and spunding valve are incorporated in the blow-off line on the side of the fermenter with a ball valve at the end for capping and pressurizing the tank. The PRV is always mounted in the center of the cooling coil cap, out of the way of glycol lines. It makes for a very clean and uncluttered, as well as highly efficient, setup. And I use it exactly how you plan to use yours. I'm very happy and impressed with what is available to home brewers these days. But with that ability also comes the responsibility to be mindful of potential unseen risks, just as with any other advanced tool.

Happy (and safe) brewing,

Brooo Brother

 

[Vale71]

Thanks for the detailed reply. Attached photo is the set up I was thinking. Would allow me to use blow off tube for majority of fermentation and like you mentioned, shut it off during final portions to build up some pressure. My primary goal is to minimize cold side oxidation and I like the idea of being able to use spunding valve (or to force carbonate for pressure transfer) without having to take anything off (i.e. switching from blow off tube to gas manifold). Less interested with pressure fermentation although I am looking to do a lot of lagering so I wouldn't rule it out.

This set-up seem reasonable? overkill? any ways you can see to minimize bulk and accomplish same goals? It seems like only way using a spike unitank given they only have one 1.5" TC port on top.

It's perfect but you're probably getting close to the fermenter's tipping point, at least when it's empty...