Macurco GD-6 Combustible Gas Detector, Controller and Transducer, 12-24VAC or 12-48VDC

The Macurco GD-6 is a low-voltage combustible gas detector and ventilation controller designed to monitor methane (natural gas), propane, or hydrogen in commercial buildings. Featuring a 0-50% LEL digital measurement range, selectable gas settings, a 5A SPDT fan relay, and a 0.5A alarm relay, it supports automatic ventilation and emergency notification. The detector operates on 12-24VAC or 12-32VDC and provides a configurable 4-20mA analog output, internal buzzer, and three-digit LED display. It is ETL listed to UL 2075 and ULC-S588 for combustible gas detection.

Macurco GD-6 Combustible Gas Detector and Ventilation Controller

The Macurco GD-6 Combustible Gas Detector is a low-voltage, commercial-grade gas monitoring device engineered to detect combustible gas concentrations and control ventilation or alarm equipment. Designed for methane (natural gas), propane (LP gas), and hydrogen detection, the GD-6 combines a gas sensor, programmable controller, and analog transducer in one compact wall-mounted assembly. It uses a catalytic bead (pellistor) sensing element to measure combustible gas concentrations as a percentage of the lower explosive limit (LEL), helping identify potentially hazardous gas accumulation before concentrations reach explosive levels. Typical applications include parking garages, boiler and mechanical rooms, commercial kitchens, battery charging facilities, maintenance shops, warehouses, and other commercial spaces requiring fixed combustible gas monitoring.

The GD-6 provides a digital measurement range of 0-50% LEL and allows installers to select methane, propane, or hydrogen as the target gas through its configuration interface. The detector incorporates a 5A single-pole, double-throw (SPDT) fan-control relay for activating compatible ventilation starters, exhaust fans, louvers, or other control equipment. The fan relay activation threshold is adjustable, with a manufacturer-documented default of 10% LEL. A separate 0.5A alarm relay can be configured for normally open or normally closed operation, with a default alarm threshold of 20% LEL. Programmable fan activation delays, minimum run times, and latching options allow ventilation operation to be coordinated with the monitored environment. A 4-20mA analog current-loop output represents the measured gas concentration for integration with compatible monitoring equipment.

Designed for standalone combustible gas monitoring or integration with building control systems, the Macurco GD-6 can interface with compatible fire and security control panels, ventilation control equipment, and building automation systems. It supports integration with the Macurco DVP-120 detection and ventilation control panel and compatible controllers accepting relay contacts or 4-20mA analog signals. Its built-in three-digit LED display provides a local gas concentration indication, while a configurable 85 dBA internal buzzer supplies audible notification when enabled. The detector includes internal diagnostics that monitor operating faults and initiate configured trouble responses through the alarm and fan-control circuitry. A field calibration interface supports gas testing and calibration using the appropriate certified gas and manufacturer-approved equipment. Its flexible outputs allow the detector to support automatic exhaust ventilation, gas shutoff valve control, and supervisory alarm reporting within a properly designed system.

The Macurco GD-6 operates from a Class 2 low-voltage power source rated at 12-24VAC or 12-32VDC, with maximum power consumption of approximately 3 watts. The detector mounts to a standard 4-inch square electrical box using removable terminal connectors for power, fan control, alarm signaling, and analog output wiring. Its dark gray enclosure measures approximately 4.5 inches high, 4 inches wide, and 2.125 inches deep, with a shipping weight of approximately 1 pound. The manufacturer specifies an operating temperature range of 0 F to 125 F (-18 C to 52 C) and 10-90% relative humidity, non-condensing. Correct installation height depends on the selected gas: methane and hydrogen detectors are mounted near the ceiling, while propane detection requires placement nearer the floor because propane is heavier than air.

The Macurco GD-6 is ETL listed to UL 2075 and ULC-S588 for applicable combustible gas detection applications, with additional manufacturer references to UL 61010-1 electrical safety requirements. Current manufacturer literature identifies a typical monitoring coverage area of up to 1,257 square feet, subject to room geometry, airflow, ventilation, and gas distribution. The GD-6 is intended for approved non-hazardous commercial locations and is not designed for installation in classified hazardous areas or as an unrestricted explosion-protection system. The device requires periodic functional testing, calibration verification, and sensor maintenance according to Macurco's instructions. Unlike the line-voltage GD-12 model, the GD-6 is powered from an external low-voltage supply. Its selectable gas detection, programmable control relays, and analog monitoring output provide a flexible solution for commercial combustible gas detection and automated ventilation management.