Description

The Honeywell RM7890A1015 is a microprocessor-based On-Off primary burner control relay module in the 7800 Series, listed under the full catalog number RM7890A1015/U. This listing includes the R7847A1033 Rectification Flame Amplifier, which plugs directly into the relay module and is required for operation. Refer to manufacturer documentation to confirm compatibility with your specific application.

The RM7890A1015 operates at 120 VAC (+10/-15%), 50/60 Hz and is designed for automatically fired gas, oil, or combination fuel single-burner applications. It performs automatic burner sequencing including pilot ignition, flame supervision, system status indication, self-diagnostics, and lockout on flame failure. The intermittent pilot system offers a selectable Four (4)-second or Ten (10)-second pilot flame establishing period. Five (5) front-panel LEDs display power, pilot, flame, main, and alarm status; the power LED blinks a fault code on safety shutdown. Non-volatile memory retains operational history and lockout status after power loss. Maximum total connected load is 2000 VA, with a 15A maximum fuse (type SC fast-blow) for the total connected load.

The R7847A1033 is a solid-state rectification flame amplifier recommended for cycled heating equipment. It plugs into the 7800 Series relay module via a keyed printed circuit board edge connector and responds to rectified signals from flame rods (C7004, C7005, C7007, C7008, C7009, Q179), rectifying photocells, or C7012A/C UV detectors. Flame failure response time is 2.0 or 3.0 seconds (FFRT); minimum acceptable flame signal is 1.25 Vdc, with a 0.0–5.0 Vdc display range. The Dynamic Self-Check circuit tests detectors and all electronic components in the flame detection system, causing the relay module to lock out on safety shutdown if a flame detection system failure is detected. A subbase (e.g., Q7800A) is also required for operation and is not included.

Technical Specifications

• Brand: Honeywell
• MPN (Relay Module): RM7890A1015 / RM7890A1015/U
• MPN (Flame Amplifier): R7847A1033
• Type: Primary Burner Control / Flame Safeguard Relay Module with Rectification Flame Amplifier
• Series: 7800 Series
• Supply Voltage: 120 VAC (+10/-15%), 50/60 Hz (±10%)
• Power Dissipation: 10W maximum
• Maximum Total Connected Load: 2000 VA
• Fusing (Total Connected Load): 15A maximum, type SC fast-blow
• Pilot Type: Intermittent
• Pilot Flame Establishing Period: Selectable 4-second or 10-second
• Status Indicators: Five (5) LEDs — Power, Pilot, Flame, Main, Alarm
• Memory: Non-volatile (retains history and lockout status after power loss)
• Fuel Compatibility: Gas, Oil, Combination Fuel
• Amplifier Type: Rectification (R7847A1033)
• Compatible Flame Detectors: Flame Rods C7004, C7005, C7007, C7008, C7009, Q179; C7012A/C UV Detectors; Rectifying Photocells
• Flame Failure Response Time (Amplifier): 2.0 or 3.0 seconds
• Minimum Acceptable Flame Signal: 1.25 Vdc
• Flame Signal Voltage Range: 0.0–5.0 Vdc
• Amplifier Self-Check: Dynamic Self-Check (Ampli-Check)
• Amplifier Color Code: Green
• Amplifier Connection: PCB edge connector, keyed for proper orientation
• Operating Temperature: -40°F to +140°F (-40°C to +60°C)
• Storage Temperature: -40°F to +150°F (-40°C to +66°C)
• Humidity: 85% relative humidity continuous, noncondensing
• Vibration: 0.5G continuous
• Relay Module Dimensions: 5 in. wide x 5 in. high x 5.25 in. deep (with Q7800A subbase); 6.09 in. deep (with Q7800B subbase) — 127 x 127 x 133 mm / 155 mm
• Amplifier Dimensions (L x H x W): 3.85 in. x 5.45 in. x 2.15 in.
• Amplifier Weight: 0.29 lb
• Country of Origin: Mexico
• Approvals: UL Listed (File No. MP268, Guide No. MCCZ); CSA Certified (LR95329-3); Factory Mutual Approved; IRI Acceptable; FCC Part 15 Class B
• Optional Accessories: S7800A Keyboard Display Module (KDM), S7810M Modbus Module, Data ControlBus Module, Remote Display Module, S7820 Remote Reset Module
• Required (Not Included): Q7800A or Q7800B Subbase