Field Controls 46198901 Control

The Field Controls 46198901, specifically the Model 4" MG1, is a professional-grade double-acting barometric draft control designed for precise combustion stability in gas-fired furnaces and boilers. Engineered for high-efficiency venting systems, this 4-inch regulator stabilizes erratic automotive drafts caused by fluctuating outdoor temperatures and wind velocities. By maintaining a constant negative pressure between .01" and .1" water column (WC), the MG1 prevents high-velocity flue gas bypass, ensuring maximum heat transfer within the heat exchanger and reducing overall fuel consumption.

This HVAC draft regulator is an essential component for conversion burner installations, sidewall power venters, and mechanical draft inducers where standard draft hoods are incompatible. The double-acting gate design effectively relieves positive vent pressures as low as .01" WC, protecting the appliance from backdrafting and potential gas spillage. Constructed with a heavy-gauge galvanized steel housing and a counterbalanced damper, the 46198901 allows for simple, accurate field calibration using the included washer-type weights. This ensures your gas atmospheric equipment reaches peak thermal efficiency while adhering to strict NFPA 54 and mechanical code ventilation requirements.

• Precise Draft Calibration: Fully adjustable from .01" to .1" WC to match specific appliance flue requirements.
• Double-Acting Protection: Effectively relieves positive pressure to prevent combustion gas spillage in the mechanical room.
• Enhanced Combustion Efficiency: Stabilizes airflow to allow for consistent CO2 levels and optimized fuel burn rates.
• Rugged Construction: Durable galvanized steel build designed for long-term reliability in high-temperature venting environments.
• Universal Mounting: Includes a collar for streamlined installation on 4-inch single-wall vent pipes.

How do I adjust the draft setting on the 4" MG1?
Adjustments are made by adding or removing the provided washer-type weights from the weight holder chain. Use a manometer to verify the draft at the appliance outlet during steady-state operation.

Can this be used on vertical or horizontal flue pipes?
Yes. The unit is field-adjustable for either configuration. For horizontal runs, ensure the weight lever screw is moved to the lower hole to maintain proper gate balance.

When is a double-acting control required instead of a standard draft hood?
Double-acting controls like the MG1 are required for gas appliances utilizing power venters or draft inducers, and for conversion burners where precise draft regulation is necessary for safe operation.

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Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.