We will add to this as we think of problems we can solve!
We get very distressed over bad beer over here in’t shed. Probably not as distressed as you if it’s your bar that’s serving the bad beer but pretty close; we take it very personally. As a ‘for instance’, my phone rang this evening during my sacrosanct couch hour; it was a beer customer in distress though and as the fifth emergency service I just couldn’t ignore it. The problem in this instance was flat beer, which upsets us as much as it upsets you, so what might be the cause? More importantly, what might be the solution?
So; basic checks:
Is there beer in the keg? I know, sorry…
Is there gas in the cylinder? If the gas runs out and you carry on dispensing the system will use whatever gas it can find to put the beer through the tap. It will use the gas in the headspace of the keg and then the gas in solution will try to equalize… Sorry – got all technical there for a moment. Make sure there’s gas and it’s turned on
Are you using the right gas? Most beers will dispense very happily under 60/40. The flip side to that is many, many beers will go bonkers and turn into a foamy pain in the arse under 30/70 and it’s very easy to confuse the two gases. Check which gas your beer needs and use the apporopriate one.
Are there any restrictions? Check for kinks in any pipes, particularly around the keg coupler, to make sure that gas is getting into the keg
Gas Pressure? For mixed gas we are looking for 25psi minimum and 35-40psi maximum at the secondary regulator. for us trying to troubleshoot home bars we have to accept that we are up against ambient temperatures and that goes for the gas too. The gas might be up and down a bit if it’s baking hot where it’s stored so do expect some fluctuations.
Has the regulator gone to Funky Town? I got a call out to one of our own mobile bars which was dispensing really slowly. We use new regulators in all our mobile bar setups, this one still had the protective film on the gauges, but it was clearly doing something odd. The primary dial was making a strange little ‘ticking’ movement and the only way I could get it to dispense was stay on site and adjust it up and down as needed. For me there are no serviceable parts on beer gas regulators so this needed replacing; beer gas regulators can fail so be suspicous of them.
Hygiene? Far, far, far and away (not where Shrek lives – not that far away) the most common cause of flat beer is something that needs cleaning and it’s usually either glasses or beer lines. People find it a tricky concept to buy into but yeast particles love beer lines, shine a torch through them and see for yourself, and glasses washed but not rinsed are clean but not really beer clean. Dishwashers do a very good job of cleaning glasses but the very best thing you can do for them is a rinse under a hot tap.
In our instance here it was glasses. I was fairly convinced it was when I set off so I took one of my own with me. When we wash glasses it’s hard to believe that they can be the cause of any problem – they’re clean right? – when we’re troubleshooting our home bars but the truth is – boring science bit here about detergent film buildup that I don’t totally understand myself – that washing up liquid and beer don’t play well together.