Description
The Honeywell RM7897C1000 is a microprocessor-based primary burner control module designed for automatically fired single-burner applications using gas, oil, or combination fuels. Operating on 120 VAC, 50/60 Hz, it provides complete control sequencing, flame supervision, diagnostics, and safety shutdown. The module supports programmable post-purge timing, delayed main valve operation, and selectable pilot type for flexible system configurations.
Technical Specifications
| Condition |
New/Never Used Surplus |
| Brand |
Honeywell |
| Category |
HVAC |
| Part Number |
RM7897C1000 |
| Subcategory |
Burner Control |
| Series |
7800 Series |
| Product Type |
Microprocessor Relay Module |
| Voltage |
120 VAC ± 10 %, 50/60 Hz |
| Application |
On-Off Primary Control with Pre- and Post-Purge |
| Flame Establishing Period |
4 s or 10 s (selectable) |
| Main Flame Establishing Period |
10 s / 15 s typical (based on configuration) |
| Pilot Type |
Selectable (interrupted / intermittent) |
| Pre-Purge |
Determined by ST7800A Purge Timer Card |
| Post-Purge |
Programmable using S7800A1142 KDM |
| Delayed Main Valve |
Yes |
| Interlocks |
Selectable airflow and safety interlocks |
| Memory |
Nonvolatile; retains fault and history logs |
| Diagnostic Interface |
Local/remote annunciation, optional Modbus or Data ControlBus™ |
| LED Indicators |
5 LEDs (Power, Sequence, Fault, Flame, Lockout) |
| Run/Test Switch |
5-position for setup and commissioning |
| Flame Amplifier Compatibility |
Plug-in amplifiers (rectification, UV, IR types) |
| Operating Temperature |
–40 °F to +140 °F (–40 °C to +60 °C) |
| Vibration Rating |
0.5 G environment |
| Enclosure Type |
Enclosed, dust-protected relay module |
| Dimensions (L × W × H) |
7.25 in × 7.0 in × 5.5 in (approx.) |
| Weight |
2.67 lb (1.21 kg) |
| Compliance |
UL Listed, CSA Certified, CE Compliant |
Information About RM7897C1000
The RM7897C1000 belongs to Honeywell’s 7800 Series of relay modules, engineered for full-function primary burner management. It coordinates the pre-purge, ignition, flame establishing, main flame proving, and post-purge stages, ensuring safe burner operation. This model features a delayed main valve and a programmable post-purge function, configurable using the S7800A1142 Keyboard Display Module (KDM). Equipped with a nonvolatile memory, the RM7897C1000 stores event history and lockout information for post-failure analysis. It also offers fault annunciation through five sequence LEDs and a blinking fault indicator, while interchangeable plug-in amplifiers allow flexibility with various Honeywell flame detectors.
Key Features:
- Automatic Burner Sequencing: Manages pre-purge, pilot ignition, main flame proving, and shutdown cycles automatically.
- Programmable Post-Purge: Post-purge timing adjustable using the S7800A1142 KDM for optimal heat-exchanger cooling and safety.
- Delayed Main Valve Feature: Adds a controlled delay between pilot and main valve opening to ensure stable ignition.
- Selectable Flame Establishing Period: Configurable 4-second or 10-second pilot flame establishment to match system requirements.
- Advanced Diagnostics: Integrated system and self-diagnostics with LED fault codes simplify troubleshooting and maintenance.
- Interchangeable Plug-In Amplifiers: Compatible with multiple Honeywell flame sensors (UV, IR, or rectification) for detection flexibility.
- LED Status Indicators: Five LEDs provide visual feedback for sequence steps, system power, and fault conditions.
- Nonvolatile Memory: Retains operational history and lockout data after power loss for reliable maintenance records.
- Flexible Interlock Options: Selectable interlock supervision for airflow, fuel valves, and ignition safety.
- Optional Communication Interface: Supports PC connection, Modbus integration, and Data ControlBus™ for advanced monitoring.
The RM7897C1000 delivers the control precision, safety integrity, and configuration flexibility essential for industrial and commercial combustion systems.
