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From above we can tell that: -

1/ at the same pressure as your beer gets colder it will take up more gas

2/ at the same temperature as the pressure increases your beer will take up more gas

Sum it up

Colder and higher pressure more fizz.

Warmer and lower pressure less fizz.

Given that and that we can lookup the desired amount of CO2 in a beer (yes that will vary from style to style)

On the

Carbonation Table from Braukaiser we can see the amount of fizz where the lines from temperature and pressure meet.

I rang Toohey's once and asked them, they told me 4.75g/L

Which raises another point how do we measure the amount of fizz in beer?

The modern metric method is in grams of CO2 / 1L of beer based on temperature in Celsius and pressure in kPa

The old fashioned American method is Volumes based on Fahrenheit and Psi.

This is my only concession to silly non-systematic ways of measuring stuff

If you put a glass of water (de-gassed water) in a closed box filled with 100% CO2 at ~20oC and left it there for a few days it would take up some CO2, until it reached an equilibrium (remember that's the same amount of CO2 going into the water as is coming out). With really good lab scales you could measure (weigh) the amount and you would find you have 0.9 Volumes of CO2 in solution, I would call it 1.8g/L of CO2 in solution. It sounds silly but the old imperial standard temperature was 60oF (15.6oC ) at that temperature it would be 1 volume.

So if you see 2.5V (Volumes) of CO2, double it and you get 5.0g/L (well its 1.98 times but 2X will do). Likewise halving g/L will give you Vol.

There are three ways to measure Pressure, the metric kilopascal's (kPa), Atmospheres or Bar (is a small difference) that's the standard air pressure at sea level, and the antiquated Pounds per square inch Psi

Roughly 1Bar = 101.3kPa = 14.7Psi

Three ways to measure Temperature, The metric Celsius, the scientific Absolute which is Degrees C +273.15 and the incomprehensible Fahrenheit.

I'm going to stick to the metric system, if for no other reason than that all the calculations we use are done in metric and then converted to Imperial and Volumes, especially if we start talking about priming with sugar(s). One other reason I like metric it makes sense! another is all my gauges have kPa and Bar (the ones with Psi got hit with a hammer).

So from here on Volume it's all in L, Temperature in oC, Pressure in kPa

If you want to convert the answers to some other units your on your own (well Google will help)

If you have a look at the equation for carbonation in the link above you can see its done in g/L, Bar and the temperature is oC +273.15 (Abs), I long ago turned it into an Excel Spreadsheet called Fizzzzzzzz which is actually easier to use than the table.

We can control the amount of Fizz in a beer by varying the Temperature and the Pressure

If we put a keg of flat beer in the fridge, get the beer cold and apply pressure over time the amount of dissolved CO2 (fizz) will go up. To have control of the process we need to know the temperature and the pressure.

Both are equally important.

You said you brought a Kegerator, I'm going to assume it has a fan in it and a little digital readout displaying the temperature. If it hasn't got a fan put one in (just a little computer fan would do) a domestic fridge can be 5oC different between the top and bottom which means that as the keg empties the beer gets colder and at the same pressure the beer will get more fizz. A fan will keep it the same right through the keg.

Given the beer you said you like I am going to suggest you start at 4.75g/L and 4oC (pretty much a pub serve for mass market lager)

If we look at the

CO2 content in g/l based on Celsius and kPa
In the left hand column (temperature in oC) and follow the 4 row... we come to 4.7 which is pretty close. Follow the column up and you will come to 0.7 under "head pressure" note that that's a bit like like a tachometer on a car where 2 is 2,000, 5 is 5,000. In this case its hundreds not thousands, 0.7*100= 70kPa

If you leave the beer in the kegerator at 4oC and 70kPa for about a week, it will have 4.7g/L of dissolved CO2, should taste the way you want.

I think its a good time to take a beak (and have a beer). We can look at speeding it all up next if you like but just make sure that the head is wrapped around what we have covered so far.

Time to let me know if you are keeping up. Very good idea to put a thermometer in a glass of water and leave it in the kegerator over night and see what the temperature really is, not what the digital says, often a bit of a difference. (get a decent thermometer).

Mark