The devices is accurate to 0.01.
You manually set the temperature and it will apply an offset.
The tip has a reservoir of de-ionized water as it apparently needs to be stored wet.
Calibration
It comes with two calibration solutions:
pH 7.01
pH 4.01
You need to split both of these into two batches and before you calibrate with each, you first swirl the electrode in one solution before the other.
You need to accurately check the temperature of the solution before you measure the pH.
The temperature dial, in my view, is crap. Why does it take 6 marks between 25, 7 if you include zero. This means that each mark has a step value of 4.16. Why this is the case is any ones guess.
Anyhow I managed to calibrate the device.
But I managed to spill the container that has the de-ionized water that the electrode needs for storage. Not I have to dig around online for it. But I think it needs to be shipped from the U.S. Anyhow it will be good enough for the next brew day.
We will need to take a sample from the mash and allow it to cool down as the electrode would be damaged by the high temperature of the mash.
One think that I realized is that it is a good thing to have some distilled water on hand to wash the electrode before and after taking a reading.
Lastly, being able to now check the pH of the water that we will be using, this value is actually different to that which was given in the Murphy and Sons water report. I will need to go back to the the Brewers Friend Mash Chemistry and Brewing Water Calculator and check to see if this make a difference to the salts additions.
Update!!!
After calibrating I tried measuring the calibration solutions and found that it was 0.03 out for both. For now I am happy with that.
So I decided to test my tap water.. 7.6.. huh?
Murphy and Sons water report tested the pH of my tap water as 6.93.
Ok so the Southern water report states:
Hydrogen ION (pH) : Min: 7.08 : Avg: 7.361 : Max: 7.7
So this is within range.
Then I tested the water prepared for tomorrows brew.
8.6......!!
I was not expecting that. If the reading is correct, boiling my tap water for an hour makes it a lot more alkaline/base. I now want to check the meter again with the calibration solution, but I already ditched them. So now I need some new ones. I managed to buy some online. It seems that its standard to use 4.01 and 7.01 solutions for calibration so they are generally available.
What is not generally available is the Milwaukee MA9015 Storage Solution that I managed to spill. But this is not generally available. I found 220ml for $15 on Amazon but with delivery its £35. Managed to find 20ml on Ebay, with delivery is £8 !!!! Obviously went for this but it was too easy to spill and I expect I will end up laying out for the 220ml bottle at some point.
Just read this product maintenance page that didn't come with the unit, and I now wish it had. It says that in the absence of MA9015 solution the 4.01 solution can be used. Oh well I have some of that on its way in the post. Interestingly it also says never to store in distilled or de-ionized water. However I have also read that the storage solution should be washed off with distilled water before use. I assume that this is because its pH 4 which could affect the reading unless the test solution is large enough.
UPDATE 2015-09-23 18:14
Received calibration fluid from ebay seller in the same packaging that I received with the unit. Checked and calibrated both at 15C and 25C and they took slight adjustments @<0.03. So happy that mash pH checked for Brew Day #3 is correct enough.
Following the calibration I have filled the electrode storage chamber with 4.01pH buffer solution to bridge the time it takes for the storage solution to arrive from the U.S.
Also received Lactol, 80% Lactic acid. Which will be deployed in Brew Day #4. As the range that we can add to the mash for a meaningful movement is between 2ml to 5.1ml, we will need to be able to accurately measure the mash pH. I have also purchased some new test paper strips that we can use as a sense check.
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