How to Adjust the Low Temperature Setting on Glycol Chiller of My Brewery?

How to Adjust the Low Temperature Setting on Glycol Chiller of My Brewery?

Normally the glycol chiller will be set as a temp range after manufacturing. 

The range is often between -5 celsius to 30 celsius(minus 41F to 86F).

But some brewers in brewpub or brewery want to adjust it lower during summer, 

so how to adjust the set low temperature? 

This particular manual does not show me how to lower the set point below the minimum 50 degrees Fahrenheit. 

It says the menu range is -41 up to 86 but it does not allow me to move it.

 Can you please provide an electrical diagram of this exact Chiller and info how to change the thermostat set point below 50f?

Hold down the up botton and enter botton at the same time. there requires a passwords.

The passwords is 4561( I am not sure if the primary user change it or not)

Enter manufacturer parameter settings

The menu botton can allow transposition, the up and down botton can change the number.

Choose temp set-----the lower temperature-change the set temp to -50F

At the same time, choose the low temperature protect to -55.4F

If the above is not success, then please enter user setting and check if the " temp lock" open?

If yes, please close it and reset the temp of low temperature.