I'm having some faults on my glycol chiller that I've managed to figure out what the problem is but don't know the impact of the solution. I found out that my chiller is faulting on low glycol temperature on the supply line to the brewery. In looking at the glycol system designs in the refrigeration section it appears that I have a 2nd generation design for a system, that is, the glycol supply for the brewery exits directly from the evaporator. On this line (there is also a smaller line returning the glycol to the holding tank) there is a temperature probe with a Johnson Controls thermostat. This is what was tripping out the compressor. It was set to about 27 deg F and my glycol setpoint (regulating the temperature of the glycol in the holding tank) was set for -1.5 deg C. The system was functioning just fine except that the supply glycol setting was overriding the tank glycol setting and the compressor was being cycled based on it.
The questions; is this a problem at all or is this just the way the 2nd generation type systems work? What should the supply glycol thermostat be set at? What are the results of lowering the setting (other than risking icing the FV due to too low a temperature)? I guess I'd rather have the system regulating temperature through the digital single loop controller rather than the thermostat with a rotary dial that is maybe +/- 5 deg F in accuracy.
As an FYI this is a bastardized system built by Maneurop that their engineering department says they don't do any more and have no record of or drawings/manuals for.
The questions; is this a problem at all or is this just the way the 2nd generation type systems work? What should the supply glycol thermostat be set at? What are the results of lowering the setting (other than risking icing the FV due to too low a temperature)? I guess I'd rather have the system regulating temperature through the digital single loop controller rather than the thermostat with a rotary dial that is maybe +/- 5 deg F in accuracy.
As an FYI this is a bastardized system built by Maneurop that their engineering department says they don't do any more and have no record of or drawings/manuals for.
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