I'm new to RIMS and need advice

I currently brew using the AG fly sparging technique using a stainless steel pot for my mash tun. I have tried to insulate around it and recognize that there is likely heat loss (especially in my northern winter climate) so I want to begin using the RIMS technique to keep my mash temperatures closer to the target temperature.

I have purchased a March 809 pump and a RIMS tube from Brewers Hardware. I will be using a RANCO ETC to control the heat exchange power. I plan on running the pump the full time and allow the Ranco controller to turn on/off power to the heat exchange as necessary.

I use brew calculators to determine the strike water volume & temperature, then dough in, and let it set for the hour.

Is it correct to assume that my water volume at dough in will have to be higher to accommodate for the liquid running through the pump, tubing and RIMS tube?

Should I also add more water (in addition to the water running through the RIMS equipment) to the strike volume to allow for water at the top of the mash?

Am I correct to assume that the additional volume of water at dough in should then be subtracted from my sparge volume?

Lastly, do I bring the mash temperature up to the sparge temperature before I start my fly sparge or do I just shut off the recirculation and fly sparge as usual?

I plan on putting the system through a trial run without grain so I'm comfortable with the system. However, I'm concerned about my water volumes for strike/sparge and screwing up on my first batch (i.e. too little or too much water in the mash).


Feel free to share any other advise/suggestions/potential problems you see with my plan....

You should add water to account for any losses you might have. Running a water test should help you figure that out. I usually add this to my sparge water.

The little bit of water that's inside your hoses while recirculating isn't going to effect your mash. Don't worry about it.

As for your sparge temp...you should always be bringing the grains up to sparging temps before you actually start the sparge.

You may need to account for some extra volume under your false bottom if it is excessive, but usually doing 1.5 qts per lb of grain is adequate.

If you're fly sparging, you don't necessarily need to calculate your total sparge volume either. I only measure my initial strike water volume in the MLT prior to dough in and then I put several gallons more than I need in my HLT. When fly sparging, I then run it until I have collected my pre-boil volume in the brew kettle. I then leave extra hot water behind in the HLT to flush through the system when I am done brewing.

While I agree with what's posted above about bringing your mash up to sparge temp prior to fly sparging, I often don't and just introduce the HLT water at mash out temp.