The Honeywell RM7850A1019 is a microprocessor-based integrated burner control for full modulation applications. It provides automatic burner sequencing, flame supervision, system status indication, system or self-diagnostics and troubleshooting.

It has access for external electrical voltage checks. Other features include;
Application flexibility and communication interface capability.
Five LEDs provide sequence information.
Five function Run/Test Switch.
Interchangeable plug-in amplifiers.
Local or remote annunciation of operation and fault information (optional).
Non volatile memory retains history files and lockout status after loss of power.
Compatible with existing Honeywell flame detectors.

Required Components:
Q7800A, B Universal Wiring Subbases. R7847, R7849, R7861, or R7886 Flame Signal Amplifier. ST7800A Plug-in Purge Timer Card.

Consult the attached pdf for further specifications