Gleycol percentage !!

[beida]

Hi brothers 😎
I have one chiller York ec 500 (R407c)
I need to determine gleycol %
The setpoint is -1
Not : I have refractometr to test the % of propylene glycol
I'm waiting for your help ....✌
Thanks again for your time

[Magoo]

select a mix ratio for -10'C and use a hydrometer to test specific density of mix. Ethylene glycol or mono propylene glycol. Mix is by weight.

[beida]

Thanks for helping
Mr Magoo ��