The PREHEAT-X and PREHEAT-X-EXT control fixed stages of Preheat and optional modulating Preheat to maintain a desired Preheat Leaving Air Temperature Setpoint.
The Orion Controls product line allows the VCCX2 Controller to expand its features and capabilities by utilizing numerous application specific add-on modules. These modules can be used as a stand-alone or as expansion modules communicating with a VCCX2 Controller via a modular cable.
These can be used as stand-alone modules or in conjunction with the VCM-X E-BUS, VCB-X, or VCCX2 Controller.
Documentation
PREHEAT-X Extended Technical Guide