It’s a question we hear often: “What’s the best way to control my gas booster?”
The truth is, there isn’t a single answer. The right control method depends entirely on the equipment, layout, and most importantly, the application. A school’s boiler plant in Boston is very different from a backup generator in Kentucky.
Here’s a breakdown of the most common control strategies engineers use—and when each one makes sense.
The Basics: Why Controls Matter
A gas booster’s job is to supply the right pressure when equipment calls for it. But if the booster runs unnecessarily, it wastes energy, drives up maintenance, and adds wear to the system.
That’s why choosing the correct control mode is so important.
Mode I: Simple Interlock Controls
- Best for: Compact systems with equipment close to the booster (e.g., two boilers within 40 feet).
- How it works: Each boiler is wired to the booster’s control panel. When a boiler starts, the booster starts. When all boilers shut down, the booster shuts off.
- Advantages: Cost-effective, simple to wire, reliable.
- Limitations: Not practical for large or distributed facilities (skyscrapers, warehouses, multi-acre campuses) as making home-run wiring circuits becomes expensive and not practical.
Mode R: Flow-Sensing Controls
- Best for: Large facilities with distributed equipment.
- How it works: The controls monitor the system flow with an electronic gas regulating valve. The booster turns on automatically when downstream flow is detected by the specialized valve.
- Advantages: No need for wiring every piece of load equipment back to the booster.
- Impact: More sophisticated, requires additional programming and components and with that comes a bit of cost.
Mode G: Generator Controls
- Best for: Emergency standby generators.
- How it works: Dedicated programming ensures the booster reliably delivers pressure whenever the generator calls for fuel.
- Advantages: Tailored specifically for generator requirements, ensuring compliance and reliability.
Key Takeaway
There’s no one-size-fits-all control method for gas boosters. The right choice depends on system size, layout, and criticality.
- Small systems: Mode I (simple interlock).
- Large facilities: Mode R (flow-sensing).
- Efficiency-focused: Mode V (VFD).
- Generators: Mode G (standby-specific).
ETTER has decades of experience designing and commissioning booster control strategies. If you’re planning a new system—or troubleshooting an existing one—our engineers can help you select the best control approach for your application.
