I converted a sanke keg into my mash tun but have had problems having a uniform mash temp (i.e. if my temp was to low, then I would turn on the burner, but this would cause the lower part to have a much higher temp than the top of the grain bed, even with lots of stirring). So I decided to purchase a march pump to help out with this issue and thought that I would recirculate my mash under low flame to lead to a more uniform temp. My question for yall, is what is the technique here? (e.g. I'm assuming you dont want to pump grain so do you vorlauf before pumping? do you open your ball valve on the outlet of the pump to match the rate coming out of the tun? How high of a vol/rate do you recirculate?) Cheers!
it's okay to pump some grain bits, no need to vorlauf. i'm guessing you have a false bottom on the keg? Just start as slow as possible with the pump...low & slow. Sometimes I will get a bit of grain caught up in the pump so need to open the valve up a little more to get it through, so just monitor the flow for the first couple minutes until the wort starts to clear. You should have a thermometer or temp probe reading the outgoing temp and make sure you're not heating the grain bed too much.
Yep, you have the right idea. You did mention the ball valve on the outlet of the pump, which is how you want to control flow rate. The valve on the keg needs to be wide open making sure the pump stays primed with no cavitation. I would start with a low flow rate measuring the temperature and you can adjust flow rate / heat as needed...
do you use a mash temp calculator? there's plenty online. If you hit the right temp on your water there's no need to heat it, unless you're losing a ton of heat through the side of the keg. I mash in a converted cooler and i lose very little temp over the course of the mash. p.s. nice avatar beerbaron.
