# Using G40.1 for Fermentation Control

**It is strongly recommended to use a dedicated glycol chiller such as a** [**G20**](https://kegland.com.au/products/icemaster-jointech-g20-glycol-icebank-with-digital-control-220-240v) **or** [**G40 Fermentation Glycol Chiller with Digital Control**](https://kegland.com.au/products/icemaster-jointech-g40-glycol-with-digital-control-220-240v?_pos=8&_sid=e772ec364&_ss=r) **for fermentation control.**

Although the G40 can be used to control fermentation temperature it should primarily be used to
 flood a font or dispense product, instead we would highly advise a G20 primarily be used for
 fermentation control. If you were going to use the G40 for fermentation control then it is suggested
 you adhere to the following advice and steps.

It is not advised to use the agitator pump to supply glycol to cool a fermenter, this is due to this
 pump not being powerful enough to overcome the resistance of the cooling coils or large fermenter
 jacket, and hence it is advised that an external pump be used connected to an external temperature
 controller ([KL01946](https://www.kegland.com.au/mkii-10-30amp-temperature-controller-heat-cool.html)).

Furthermore, it is not advisable to use the temperature controller on the G40 as a temperature
 controller for fermentation control. This is because if the fermentation temperature is set on the
 temperature controller on the G40 it will result in the temperature of the reservoir being set to your
 fermentation temperature and hence there will not be a high enough temperature differential
 between the temperature of the glycol and the temperature of the fermenter to maintain stable
 fermentation temperatures. Instead, the following method should be employed to setup your G40
 to cool a jacketed fermenter up to 500L.

1. Connect an external pump to an external temperature controller
2. Attach tubing to the ½ inch drainage port on the G40 and connect this tube to your external
    pump
3. Attach tubing to the outlet of the external pump and attach this tube to the cooling coils on
    your fermenter
4. Run tubing from the outlet of the fermenter cooling coils back into the reservoir of the G40
5. Set the temperature on the G40 to -2°C (if using glycol) or to 2°C (if only using water in the
    reservoir)
6. Attach 10mm ID silicone tube to the “Water Out” barb and connect this silicone tube to the
    adjacent “Water in” barb. Run the agitator continuously to keep the reservoir agitated and
    prevent the reservoir from freezing
7. Insert the temperature probe of the external temperature controller into the thermowell on
    your fermenter
8. Set the temperature on your external temperature controller to your set fermentation
    temperature. This will cycle the pump on and off to supply cold glycol solution only when
    the temperature of the fermenter increases above the set fermentation temperature. When
    under load such as when cooling a fermenter it can take a longer time to cool the reservoir
    down to the set temperature on the glycol chiller. This time is dependent on a number of
    variables including but not limited to:\
   • Jacketing of the fermenter (jacketed or non-jacketed)
   \
   • Number of fermenters being cooled
   \
   • Ambient temperature
   \
   • Heat ingress