Controlling fermentation temperature

Regulating the temperature in your fermenter (3-in-1 or 4-in-1) is critical in order to obtain consistency from batch to batch and produce results that match the style of beer. If the temperature gets too warm, off-notes will be produced that will spoil the flavor you are trying to achieve. Too cold, and fermentation stops. While ale yeast can handle warmer temperature than lager yeast, even ale yeast has temperature preferences that are necessary to accommodate in order to achieve high quality beer.

Precisely controlling temperature in your fermenter is easy with the BREWHA fermenter. Through the use of the Electronic Temperature Controller ('ETC') you can precisely regulate the temperature of your beer to within 1°F.

To maintain fermenter temperature, program the Electronic Temperature Controller to the exact fermentation temperature you want for you style of beer. As the temperature moves away from the set point, the controller's temperature probe signals the controller, which then allows power through to either the heating or cooling receptacle on the ETC.

The ETC heating receptacle can either be connected to the Temperature Control Valve which will open, letting warming water in, or to the Power Control Box, turning the heating element on to warm the fermenter back up (see last paragraph for more details).

The ETC cooling receptacle can either be connected to the Temperature Control Valve, which will open, letting cooling water into the jacket (for example, cold municipal water) or connected to the Water, Beer and Wort Chiller, which will turn on, pumping chilled water through the jacket and back to the chiller reservoir. Once the programmed temperature is reached, the ETC removes power to the receptacles and stops the heating or cooling action. More information on cooling the fermenter can be read here.

(BREWtip: during fermentation, keeping the chilling or warming water within about 10 degrees (~5C) of your target temperature will effectively maintain your target temperature without causing much temperature overshoot; for example, if you want to cool your wort to 70F, using 35F water will cool it faster but will keep cooling your fermenter even when the valve/pump closes since the water in the jacket still keeps cooling causing your fermentor temperature to drop too low. It is better to use 50F or 60F water to keep the fermentor at 70F; or if using water to warm, to use 80F or 90F rather than 120F.) 

The fermenter can be warmed as needed (for example, when fermenting in a cold garage or basement or brewing a warm fermented beer such as Saison or Hefeweizen) in one of two ways. The first, as indicated above is by running warm water through the jacket. The second is by using the heating element on very low power (e.g. 2-3% output) which will keep the fermenter warm without causing any deleterious effects to the fermentation process or flavor (too much power could scorch the yeast that has settled on the element and produce off-flavors). The 240V Power Box comes with a built-in means of adjusting the output of the heating element.

2 comments

  • Hi Michael,
    If municipal water cannot be used for warming or cooling then other means are necessary. For warming, the element can be used on low power (e.g. 2-3%) to keep the fermenter warm, with no adverse effect on the yeast or flavor. The product description for the ‘240V Power Box’ discusses this.
    For chilling, an under the counter sink chiller, or for larger applications a glycol chiller, could be employed by themselves, or in conjunction with municipal water (for example use municipal water to cool after boil and a chiller to drop the last few degrees and maintain fermenting temperature). You can read more about this in the BREWinfo article ‘Maintaining low fermentation temperatures without a fridge’.

    BREWHA Equipment Co Ltd.
  • I am intrigued with your BIAC system. My one concern is how you control fermentation temperature in climates where the ground water can be close to 80 degrees in summer with ambient temps over 100. Also, in winter where ground water and ambient temps are below the desired fermentation temp, how does one keep the fermentation temp warm enough?

    Michael Riordan

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