Relay Module 120V Semi-Automatic Burner Sequencing with VPS Capability
The Honeywell RM7838B2021 is a microprocessor-based primary burner control for use in semi-automatic burner systems operating on gas, oil, or combination fuels. It is designed for interrupted pilot systems and includes integrated Valve Proving System (VPS) functionality to verify the integrity of fuel shutoff valves prior to burner ignition. This model offers automatic sequencing, flame supervision, and enhanced system diagnostics, making it ideal for commercial and industrial burner applications requiring added safety and manual start input.
Technical Specifications
- Model: RM7838B2021
- Series: RM7800
- Voltage: 120V AC (+10%, -15%)
- Frequency: 50/60 Hz
- Application: Semi-Automatic Burner Control with VPS
- Pilot Type: Interrupted
- Flame Establishing Period – Pilot: 4 or 10 seconds
- Flame Establishing Period – Main: Intermittent
- PrePurge: Set via ST7800A Plug-in Purge Timer
- Airflow Switch Check: Included
- Interlocks: Selectable
- Mounting: Q7800A or Q7800B Subbase required
- Flame Amplifier Compatibility: R7847, R7848, R7849, R7851, R7852, R7861, R7886
- LED Indicators: 5 LED lights for sequence and fault display
- Nonvolatile Memory: Stores flame signal, cycle history, and lockout conditions
- Temperature Range: -40°F to +140°F (-40°C to +60°C)
- Vibration Tolerance: 0.5 G
- Weight: 1 lb 15 oz (0.9 kg)
- Condition: New
Key Features
- Semi-automatic operation with manual burner start input
- Integrated Valve Proving System for pre-ignition valve integrity check
- Provides complete burner sequencing, shutdown, and flame supervision
- Modular design supports multiple flame amplifier types
- Nonvolatile memory retains operational history after power loss
- LED status lights for live burner sequence feedback
- Compatible with optional remote reset, annunciation, and display modules
Compatible Accessories
- Q7800A / Q7800B Subbases
- ST7800A Plug-In Purge Timer Card
- R7847, R7848, R7849, R7851, R7852, R7861, R7886 Flame Amplifiers
- S7800A Keyboard Display Module
- S7830 Expanded Annunciator
- S7810A ControlBus or S7810M Modbus Communication Modules
Industry Applications
- Industrial steam and hot water boilers
- Process heating equipment
- Fuel-fired ovens and furnaces
- Commercial combustion systems requiring valve verification
Installation & Maintenance Notes
- Mount with compatible subbase and purge timer
- Confirm VPS logic wiring is configured according to system needs
- Verify amplifier and flame sensor compatibility during setup
- Monitor system status with onboard LEDs or optional display
- Test airflow switch and interlocks regularly as part of routine maintenance
This part is normally stock.
Request a Quote now or call us at 1-800-755-2883 for expert assistance.