Hello,

We have an environmental chamber with a cascade system that uses R404 and R508 refrigerants and we need to repair it. We are finding the cost of R508 is US$350 - US$1100 per pound depending on where you get it. And the minimum purchase quantity is 5 pounds, we only need 1 pound.

The system is designed to go down to -70 deg C.
We may consider changing the low temperature setting to -50 deg C if there is a lower cost alternative.
Does anyone know if there are any alternative refrigerants that may be less expensive and more readily available than R508?

Art