50HCQA

Duct smoke sensor

 

controller

 

Conduit nuts

 

(supplied by installer)

 

Conduit support plate

 

Terminal block cover

Controller housing

Cover gasket

and electronics

(ordering option)

Conduit couplings

Controller cover

 

(supplied by installer)

 

 

Fastener

 

(2X)

 

Trouble

Alarm

Power

 

Test/reset

 

switch

C08208

Fig. 58 - Controller Assembly

Air is introduced to the duct smoke detector sensor’s sensing chamber through a sampling tube that extends into the HVAC duct and is directed back into the ventilation system through a (shorter) exhaust tube. The difference in air pressure between the two tubes pulls the sampled air through the sensing chamber. When a sufficient amount of smoke is detected in the sensing chamber, the sensor signals an alarm state and the controller automatically takes the appropriate action to shut down fans and blowers, change over air handling systems, notify the fire alarm control panel, etc.

The sensor uses a process called differential sensing to prevent gradual environmental changes from triggering false alarms. A rapid change in environmental conditions, such as smoke from a fire, causes the sensor to signal an alarm state but dust and debris accumulated over time does not.

For installations using two sensors, the duct smoke detector does not differentiate which sensor signals an alarm or trouble condition.

Smoke Detector Locations

Supply Air —

The Supply Air smoke detector sensor is located to the left of the unit’s indoor (supply) fan. See Fig. 60. Access is through the fan access panel. There is no sampling tube used at this location. The sampling tube inlet extends through the side plate of the fan housing (into a high pressure area). The controller is located on a bracket to the right of the return filter, accessed through the lift-off filter panel.

Duct smoke sensor

Exhaust tube

Exhaust gasket

See

Detail A

Intake gasket

TSD-CO2 (ordering option)

Plug

Sampling tube

(ordered separately)

Coupling

Detail A

Magnetic test/reset switch

Sensor housing and electronics

Cover gasket

(ordering option)

Sensor cover

Smoke Detector Sensor

C08245

Fig. 60 - Typical Supply Air Smoke Detector Sensor

Location

Return Air without Economizer —

The sampling tube is located across the return air opening on the unit basepan. See Fig. 61. The holes in the sampling tube face downward, into the return air stream.

Alarm

Power

Trouble

Dirty

C08209

Fig. 59 - Smoke Detector Sensor

The sampling tube is connected via tubing to the return air sensor that is mounted on a bracket high on the partition between return filter and controller location. (This sensor is shipped in a flat-mounting location. Installation requires that this sensor be relocated to its operating

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Carrier 50HCQA installation instructions Smoke Detector Locations, Supply Air
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50HCQA specifications

The Carrier 50HCQA is a cutting-edge rooftop air conditioning unit designed for commercial applications, combining efficiency, reliability, and advanced technology to ensure optimal indoor climate control. This model stands out in Carrier's extensive range of HVAC solutions, showcasing a blend of innovative features suitable for diverse building types.

One of the key features of the Carrier 50HCQA is its high-efficiency compressor. With variable-speed capabilities, the compressor adjusts its output to meet the precise cooling or heating demands of the space, promoting energy savings and consistent temperature management. This flexibility results in reduced energy consumption, making the 50HCQA an environmentally friendly choice for businesses looking to lower their carbon footprint.

The 50HCQA integrates advanced microprocessor controls, streamlining operation and enhancing user interaction. This technology allows for sophisticated diagnostics, monitoring, and scheduling, giving facility managers the tools they need to optimize system performance. The user-friendly interface ensures that settings can be easily adjusted, and real-time performance metrics can be accessed to ensure efficient operation.

In terms of construction, the Carrier 50HCQA is built with durability in mind. The unit features a robust cabinet design with a galvanized steel construction that is resistant to corrosion. This feature enhances the longevity of the unit, making it suitable for a variety of weather conditions. Additionally, the insulated casing reduces sound levels, providing a quieter operation that is particularly beneficial in noise-sensitive environments.

Another significant characteristic of the 50HCQA is its environmentally responsible refrigerant options. It utilizes R-410A refrigerant, which has a lower Global Warming Potential (GWP) compared to traditional refrigerants. This aspect not only meets regulatory standards but also supports users in making eco-friendly choices in their HVAC systems.

The 50HCQA also supports a range of optional accessories, including economizers for enhanced energy efficiency and improved air quality. This allows for increased outdoor air intake during suitable conditions, which can significantly contribute to enhancing indoor air quality—an essential factor for occupant comfort and health.

In conclusion, the Carrier 50HCQA is an exemplary model in the commercial HVAC sector, delivering powerful performance, advanced control technologies, and robust construction. Its energy-efficient design, user-friendly controls, and eco-conscious refrigerant options make it a top choice for businesses aiming to invest in sustainable and reliable climate control solutions.
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