Fault A4 typically indicates a KM-BUS communication issue

a reversible lead motor or a specific CCW model must be used

this DSI control board utilizes a microprocessor to ensure precise timing and diagnostic LED feedback for troubleshooting

it is designed for globe valves like the VB-7000 series and can be adapted for damper control using the appropriate AM-601 linkage kits

High Load Capacity: Rated for 10 Amps

Resideo CPR8 Regulator 321702-401 Fault A4 typically indicates aThe Resideo CPR8 Regulator is a critical replacement component for the CPRD8 bypass damper system, engineered to manage pressure fluctuations in constant volume and variable air volume HVAC systems. Designed for heavy duty zoning bypass control, this regulator ensures the barometric damper maintains appropriate static pressure as zone dampers open and close. By utilizing a precise weighted pressure regulator mechanism, the CPR8 prevents excessive air