581J

Return Air Enthalpy Sensor —

Mount the return-air enthalpy sensor (33CSENTSEN) in the return-air section of the economizer. The return air sensor is wired to the enthalpy controller (33CSENTHSW). See Fig. 54.

 

 

 

 

4-20

24V

 

 

 

RED

 

 

PL6-1 (24-V)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Main

GND

 

 

 

BLK

 

 

PL6-4 (COM)

 

 

 

 

+ VDC

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CTB ECON

 

 

 

 

Out

LOW

 

 

 

GRA

 

 

7

 

 

 

 

 

 

 

 

(RTU Open: to J2-6)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Outside Air

 

 

 

 

 

 

 

 

 

 

 

 

 

Enthalpy Switch

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+ 24-36

 

 

 

 

Return Air

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VDC In

 

 

 

 

Enthalpy

 

 

 

 

 

 

4-20 Main

 

 

 

 

Sensor

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Out

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C11170

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig. 54 - Outside and Return Air Enthalpy Sensor

 

 

 

 

 

 

Wiring

 

 

To wire the return air enthalpy sensor, perform the following:

1.Use a 2-conductor, 18 or 20 AWG, twisted pair cable to connect the return air enthalpy sensor to the enthal- py controller.

2.Connect the field-supplied RED wire to (+) spade connector on the return air enthalpy sensor and the

(+)terminal on the enthalpy controller. Connect the BLK wire to (-) spade connector on the return air en- thalpy sensor and the (-) terminal on the enthalpy controller.

Smoke Detectors

Smoke detectors are available as factory-installed options on 581J models. Smoke detectors may be specified for Supply Air only or for Return Air without or with economizer or in combination of Supply Air and Return Air. Return Air smoke detectors are arranged for vertical return configurations only. All components necessary for operation are factory-provided and mounted. The unit is factory-configured for immediate smoke detector shutdown operation; additional wiring or modifications to unit terminal board may be necessary to complete the unit and smoke detector configuration to meet project requirements.

Units equipped with factory-optional Return Air smoke detectors require a relocation of the sensor module at unit installation. See “Completing Installation of Return Air Smoke Sensor:” on page 36 for details.

System —

The smoke detector system consists of a four-wire controller and one or two sensors. Its primary function is to shut down the rooftop unit in order to prevent smoke from circulating throughout the building. It is not to be used as a life saving device.

Controller —

The controller (see Fig. 55) includes a controller housing, a printed circuit board, and a clear plastic cover. The controller can be connected to one or two compatible duct smoke sensors. The clear plastic cover is secured to the housing with a single captive screw for easy access to the wiring terminals. The controller has three LEDs (for Power, Trouble and Alarm) and a manual test/reset button (on the cover face).

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. 55 - Controller Assembly

Sensor Module —

The sensor module (see Fig. 56) includes a plastic housing, a printed circuit board, a clear plastic cover, a sampling tube inlet and an exhaust tube. The sampling tube (when used) and exhaust tube are attached during installation. The sampling tube varies in length depending on the size of the rooftop unit. The clear plastic cover permits visual inspections without having to disassemble the sensor. The cover attaches to the sensor housing using four captive screws and forms an airtight chamber around the sensing electronics. Each sensor includes a harness with an RJ45 terminal for connecting to the controller. Each sensor has four LEDs (for Power, Trouble, Alarm and Dirty) and a manual test/reset button (on the left-side of the housing).

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

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Bryant 581J installation instructions Smoke Detectors, Return Air Enthalpy Sensor, Wiring, System, Controller

581J specifications

The Bryant 581J is a high-efficiency gas furnace that exemplifies advanced heating technology and innovative design. Known for its reliability and comfort, the Bryant 581J offers impressive performance features that cater to both residential and commercial heating needs. One of its standout characteristics is the two-stage heating system, which allows the furnace to operate at a lower stage when the heating demand is modest, providing improved comfort and energy efficiency. This feature also minimizes temperature fluctuations, ensuring a more consistent and comfortable indoor environment.

Energy efficiency is a critical aspect of the Bryant 581J. With an annual fuel utilization efficiency (AFUE) rating of up to 96%, this furnace is designed to convert a high percentage of fuel into usable heat, which helps homeowners save on energy bills. The high-efficiency design also contributes to a reduced carbon footprint, aligning with modern environmental concerns.

The Bryant 581J is equipped with technologically advanced features, including the ComfortTech™ control system. This system enables enhanced temperature regulation and integrates easily with smart home systems, allowing homeowners the convenience of remote control through smartphones and tablets. Additionally, the furnace includes an electronically commutated motor (ECM) blower, which optimizes airflow and reduces energy consumption while enhancing the overall comfort level within the space.

Noise reduction is another key characteristic of the Bryant 581J. The furnace is engineered with sound-dampening technology, resulting in quieter operation compared to conventional furnaces. This attention to noise management makes it an appealing choice for residential applications, where peace and tranquility are crucial.

The durable construction of the Bryant 581J ensures longevity and reliability. With a robust cabinet and quality materials, it is built to withstand the rigors of daily operation. Furthermore, the furnace comes with a warranty that provides peace of mind, protecting the investment over the years.

Overall, the Bryant 581J represents a blend of efficiency, advanced technology, and reliable performance. With its high AFUE rating, innovative features, and quiet operation, it stands out in the market as a top choice for anyone seeking a dependable heating solution. Whether for new installations or replacements, the Bryant 581J is designed to meet the heating demands of today's energy-conscious homeowners.