The Espar Digi-Max D1000 heater controller serves the needs of the Airtronic D2/D4 bunk heaters, giving drivers maximum control with more real-time information and a larger display screen to accommodate things like constant heater status display, temperature set point and a run-time countdown clock. The unit also isolates problem shut-offs from routine shut-offs through a“Check Heater” indicator and simplified diagnostic service messages. For maintenance technicians, the controller offers simplified menu, allowing them to more easily program the heater’s operating parameters. Other features include a maximum run-time limiter, customized PM schedule alerts and programmable low-voltage shut-off.