It will list the required orifice size based on the manifold pressure and the altitude of the installation

Optimized System Communication: Facilitates high-speed data exchange between the ReliaTel™ control board and peripheral HVAC components

The ball checks act as a safety shut-off

Is the Carrier KH43LG073 compatible with R-410A systems

Trane SWT2327 Switch 321142-301 It will list the requiredExperienced technicians recognize the Trane SWT2327 Switch as a critical safety component for high pressure monitoring. This OEM Trane replacement part is a Single Pole Single Throw (SPST) device with a normally closed (N C) contact configuration, providing immediate circuit interruption when system pressures exceed safe operating parameters. Designed for direct mounting on the high pressure line or near the compressor, this HVAC pressure switch