Construction Considerations

  1. Electricity and water are a dangerous mix! Ground everything (pump, and electric heater if applicable) and the use of GFCI (Ground Fault Circuit Interrupt) outlets is mandatory. A GFCI outlet will trip much quicker than your garage's circuit breaker will if there is a short and this just may save your life.
  2. Make sure your false bottom has a sufficient percent-open area. It is suggested that 70% open is ideal for RIMS. The pump should not have to "suck" the wort through the grain bed, but should simply pump to the surface what naturally and quickly flows through the grain bed. If the pump has to pull the wort through the grain bed, the bed will become compacted and will "stick".
  3. Pump should be magnetically coupled. This allows for the pumping mechanism to be completely sealed off from the motor, eliminating any chance of the wort coming into contact with the drive shaft. Also allows for the control of pumping rate using a down-stream ball-valve. (Do not place the ball-valve on the inlet side of the pump, as this may cause the pump to run dry and damage the pump)
  4. Pump should also be able to pump at least 4 to 8 gallons per minute at a few feet of head. A pump between 1/50 to 1/20 horse power and 1,500 to 3,000 rpm should be sufficient.
  5. Use copper pipes or braided plastic tubing. Normal plastic tubing may get soft from the heat and collapse during pumping.
  6. Use lead free solder.
  7. Distribute the wort gently and evenly on top of the grain bed to prevent channeling, HSA, and so as not to disturb the bed.