I have an old, old temperature controller for a 25 liter reactor. I would love to build or buy a replacement, but need some help.
Setup:
Input is a thermocouple
Heating via steam, controlled with AC solenoid valve
Cooling via mixed cold/hot water, controlled with AC solenoid valve.
Current controller drives a SSR via DC.
Process includes heat to a setpoint.
Hold at setpoint for a few hours.
Cool to another setpoint.
Hold at new setpoint.
Finish.
Time intervals are not important and setpoints are manually entered.
Not looking for anything fancy. Just a replacement option.
Any suggestions? Manufacturer preferences?