​The Honeywell Q7800F1004 is a 22-terminal universal wiring adapter subbase designed to facilitate the integration of Honeywell's 7800 Series relay modules with existing RA890 or R4795 primary control systems.  This adapter subbase enables a seamless transition to the 7800 Series burner control system without necessitating a complete system rewiring, thereby simplifying upgrades and maintenance processes.

The Q7800F1004 supports burner, panel, or wall mounting configurations, accommodating various installation requirements.  It features bifurcated contacts that ensure reliable electrical connections with the 7800 Series relay modules or the S7830A expanded annunciator.  The subbase operates effectively within a wide ambient temperature range of -40°F to 140°F, making it suitable for diverse environmental conditions. ​

By providing a standardized wiring interface, the Q7800F1004 enhances system compatibility and reduces installation complexity.  Purchasing part numbers Q7800F1004, R7847A1025, and RM7890A1015 together serves as a replacement for RA890F1338.