Zero Minimum Differential: The internal pilot-operated design allows the valve to open and close effectively even at 0 PSI

How do I test the defrost sequence on the HK32EA008

The internally equalized design simplifies installation by eliminating the need for an external sensing line

which may require the AV-400 linkage instead

Johnson Controls T23A-1 Thermostat 30067439-890 Zero Minimum Differential: The internalFan Coil Thermostat, 120 240 Vac, Low Med High Fan Switching, Heat Off Cool System Switching, 50 to 90 Degree Teperature Range, 1 3 4 Degree Heating Differential, 2 1 4 Degree Cooling Differential T23A 1 is identical to T23A 1C