Providing genuine Apollo SL-2000-P photoelectric duct smoke detectors. Premium AHU fan interlocking and fire protection solution for building HVAC systems.

Apollo SL-2000-P Photoelectric Duct Smoke Detector — Premium Early Smoke Detection Solution for AHU Airflow and Building HVAC Fire Protection

In modern commercial, industrial, and high-rise residential HVAC engineering, preventing the rapid recirculation and spread of toxic smoke inside ventilation networks is a critical life-safety priority. If a fire breaks out, the Air Handling Unit (AHU) or ventilation fan can inadvertently act as a distribution mechanism, spreading lethal fumes across entire building zones before localized area smoke detectors are even triggered. The Apollo SL-2000-P photoelectric duct smoke detector serves as a vital line of defense, specifically engineered to provide early detection of smoke and products of combustion within moving airflows to solve this life-safety challenge.

What Is the Apollo SL-2000-P Duct Smoke Detector?

The model Apollo SL-2000-P is a high-performance photoelectric duct smoke detector manufactured by Apollo Fire Detectors. Utilizing an advanced, high-precision Apollo 55000-328APO photoelectric sensing head, the device is optimized to detect smoke particles within the flowing air stream of air ducts while minimizing false alarms caused by dust or humidity. Unlike standard ceiling-mounted area detectors, the SL-2000-P is housed in a rugged, installer-friendly enclosure designed to withstand harsh mechanical environments.

The device samples the moving air inside the duct via a specialized sampling tube, passes it across the inner photoelectric smoke chamber, and routes it out through an exhaust tube. When smoke particles are identified, the internal control board triggers high-capacity relay contacts to shut down HVAC fans or transmit real-time alarm signals to the building's main Fire Alarm Control Panel (FACP) or Building Management System (BMS).

Advanced HVAC Knowledge — Interlocking Applications for Emergency AHU Fan Shutdown and Fire Damper Isolation

In central air-conditioned facilities distributing air through primary supply and return duct networks, a localized fire near an intake or inside a specific zone poses a massive containment threat. If the blower fans keep operating, toxic smoke will rapidly flood every room on that ventilation loop.

To isolate fire zones and ensure immediate containment, an automated emergency interlock circuit is established using the Apollo SL-2000-P:

The Apollo SL-2000-P detector is strategically installed on a straight section of the main supply or return air duct, typically positioned downstream from air filters, bends, or mixing boxes (ideally 6 to 10 times the duct diameter away from turbulence) to ensure a laminar and consistent airflow.

A specialized sampling tube (such as the STN series, sized from 6 inches up to 10 feet to match the duct width) is extended completely across the duct cross-section to capture an accurate air sample.

The unit's built-in 10A Form "C" alarm contacts are wired directly into the AHU control panel's safety circuit—such as the Variable Frequency Drive (VFD) safety interlock loop or the blower motor's magnetic starter coil.

When smoke is detected, the internal photoelectric chamber triggers, and the Form "C" relay immediately breaks the safety circuit. This forces an instantaneous emergency trip and shutdown of the AHU fan, cutting off airflow and preventing toxic smoke migration. Concurrently, the second relay contact can be used to drop power to motorized fire dampers, closing them instantly to seal off the affected zone.

Technical Specifications Extracted from Apollo Series SL-2000-P Catalog

Key Installation and Testing Notes to Avoid System Faults

HVAC and electrical installation crews must pay close attention to the following criteria during installation:

Air Velocity Verification: The operational velocity inside the duct network must fall strictly within the 100 to 4,000 ft./min threshold. If the airflow is too sluggish, it will fail to force a representative air sample into the smoke chamber, leaving the system blind to actual fire hazards.

"No-Tools" Maintenance & Testing: The SL-2000-P features a patented clear cover and a toolless tube retention clip, enabling quick inspections. Technicians should utilize the integrated aerosol test port valve to inject test smoke (using functional aerosol sprays) directly into the housing without thâo gỡ the outer casing, maintaining the air seal.

Trouble Circuit Monitoring: Always wire the independent Form "C" trouble contact into the BMS or fire alarm monitor loop. This ensures that an immediate trouble fault signal is transmitted if the clear detector cover is missing, input power is dropped, or the inner smoke head is detached.

Why Choose the Apollo SL-2000-P via DLK TRADING SERVICE COMPANY LIMITED?

DLK TRADING SERVICE COMPANY LIMITED specializes in supplying genuine Apollo SL-2000-P duct smoke detectors imported directly with complete CO/CQ certifications for electromechanical building projects.

We maintain large warehouse stock, provide comprehensive engineering support for interlock control circuit diagrams, and deliver professional, long-term warranty policies.

Contact DLK TRADING SERVICE COMPANY LIMITED: 070 357 0101 | info@dlk.com.vn | https://dlk.com.vn/