Can you over-carbonate a keg?

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HeavensBrew

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I have an issue with storing bottled beers at a cold enough temperature and that leads to over-carbonation if not kept in the fridge. That's fine, but it makes the 2nd fridge a limiting factor.

I had accepted this, but then had a thought over the weekend..... Keg spears have a pressure release valve, so does that mean excessive pressure is released automatically and I can't have over carbed beers in kegs?

I've only just started kegging beers and it would be great if the kegs could just be cold-crashed (fridge on coldest setting for 48 hours) and then stored at around 20C until required.
 
At what point are you bottling? I used to keep my bottles in the shed at my old house and through the summer the temperatures could be far too hot but I never experienced over carbonation because of it.I have a different house with better storage now.

I’ve recently moved to corny kegs and you seem to be referring to Crusader kegs (corny kegs don’t have spears) but the Pressure relief valves on cornies are set to blow well above “over-carbonation” levels. You can buy replacement PRVs that will blow at lower pressure but even then I think the lowest Kegland sell is 35PSI which will still be a glass full of foam.
 
It's not a bottling timing issue (went through all of that), but rather the effect of temperatures that are never below 20C in the coldest place I have outside the fridge. Seems these restart the carbing process.

My assumption is that you can get away with +20C storage if the temperature drops a decent amount at night, but my winter storage temperatures are generally static and +21-24C.

I have 5l Stainless steel kegs (not the cheap party kegs). I hate waste, but I guess I should run an experiment. My other option would be to avoid priming, store and then force-carb after storage.
 
If warmer conditions re start fermentation, or carbonation, then by definition there must be sugars available for the yeast to consume. Therefore, unless we are talking about hop creep with very hoppy beers, fermentation can't have finished or carbing sugar levels are too high. I can't see how, logically, there could be any other explanation.
 
My experience with this problem began with extract kits by Festival(now full grain), which already eliminates the possibility of a screw up by me. I noted that the beet became overcarbed after a long store. So I went through a range of things that included: making sure it was not a contamination issue, triple checking the FG has stopped and still waiting additional time, reducing the sugars supplied in the kit by as much as 50%, etc.

I also tried splitting the storage of a batch between in the fridge and in the cupboard. Never had an over-carb problem with the beer in the fridge, but did with the beer in the cupboard. This even applied if the beer was transferred from the fridge to the cupboard.

Procedures for UNDER-carbed beers also prove this problem out. Whats's a common solution for an under-carbed beer? Put it somewhere warn for a week or so. In my case, my cool spot is a consistent minimum of 26C(no drop in nighttime temperature) in the summer and at least 20C 24 hours a day throughout the year. My whole location is the solution to under-carbed beer and so, by default, an environment for overcarbed beer.
 
I had accepted this, but then had a thought over the weekend..... Keg spears have a pressure release valve, so does that mean excessive pressure is released automatically and I can't have over carbed beers in kegs?
If you want to naturally carbonate in a corny keg then you'd attach a spunding valve to set a pressure limit. The PRV in the lid will let go at some point but it's said to be some really high 'emergency release' setting like 65psi or higher.

You'd want to carbonate and then cold crash so that you drop out the trub created during the secondary fermentation during the cold crash. The pressure built up during the carbonation will appear to drop during the cold crash due to the cold temperature but will rise again once you take it out and warm it up again.
 
I think I need to start force carbing my kegs. I use 5l stainless steel kegs (Dark Farm) as they fit in the fridge and run these on a soda stream bottle or cartidges. With natural carbonation I don't even need to attached the gas for the first few pints.

I could put the gas cannister and keg in the fridge nearer to when they are going to be needed. 15PSI for 4-7 days. or 25PSI and shake for a few mins.
 
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