Spunding valve or blowoff tube?

[DrDance]

I always try to defer to people with more experience in matters…so I’ll ask this forum.

I’d like to start fermenting under pressure, but I’m concerned my spunding valve might get full of crud with an active fermentation.
Does this happen? Am I overthinking this? Is it okay if it does?

I’ve had super active fermentations in the past that kinda went everywhere, even with a blowoff tube, which is why I’m hesitant.

Any help on whether extremely active fermenting is a problem under fermentation would be a great help.

TIA

 

[VikeMan]

I’d like to start fermenting under pressure,

By under pressure, do you mean at pressures higher than the very low (say ~2 PSIG) pressure needed to use a spunding valve in place of an airlock? If so, why? Do you lack the means to control fermentation temps? Need to crank up the temp to save a day or two of process time? Have you drunk the Pseudo-Lager coolaid? Some people will disagree, but IMO there is nothing about high pressure fermentations that improves (or even matches) beer as compared to a properly conducted traditional fermentation.

but I’m concerned my spunding valve might get full of crud with an active fermentation.
Does this happen? Am I overthinking this? Is it okay if it does?

It can happen, and it's not good for the valve. Some can be disassembled and cleaned. But if stuff gets into the gauge, that can be difficult/impractical to clean. When planning to use a spunding valve during active fermentation, I use use the same kind logic as if I were going to use an airlock... What's the batch size, headspace, temperature, OG, yeast strain, and pitch rate? If blowoff seems likely, start with a blowoff tube, then replace with the spunding valve (or airlock) as soon as activity slows down (and nothing (except CO2) is blowing off).

I’ve had super active fermentations in the past that kinda went everywhere, even with a blowoff tube, which is why I’m hesitant.

Fermenting under high pressure may alleviate that some, but it's not a guarantee.

 

[odie]

pressure will reduce/hinder krausen. By how much who knows. If you have adequate head space then it should not be an issue. If you are fermenting with minimal headspace, such as in a keg, well you might get krausen in your spuinding valve.

I ferment in the keg with only an inch or 2 of headspace. I use a blow off tube but surprisingly I rarely get much, if any krausen coming out.

All bets are off with a hefe or saison.

You could rig up a catch can before the spunding valve.

I typically only do lagers under pressure from the start, which don't seem to produce as much krasuen as an ale. Ales only go under pressure after peak krausen has passed.