Air¯ow Switch Ð The air¯ow switch (AFS) is a snap- acting SPDT switch that is factory installed in the PIC con- trol box. It senses the air supplied by the 39L or 39NX unit and provides the microprocessor module with a 24 vac dis- crete signal for fan status. See Fig. 35.

A length of plenum tubing connects the switch to the probe located on the fan side plate.

The air¯ow switch range is 0.05 to 2.0 in. wg with a dead- band of 0.02 in. wg at minimum set point and 0.1 in. wg at maximum set point.

NORMALLY

NORMALLY

CLOSED CONTACT

OPEN CONTACT

TURN SCREW CLOCKWISE

CLOSED

TO INCREASE AIRFLOW

CONTACT

 

TURN SCREW COUNTER-

 

CLOCKWISE TO DECREASE

 

AIRFLOW

 

 

SPDT SNAP

 

ACTING

LOW-

SWITCH

PRESSURE

 

INLET

 

HIGH-

 

PRESSURE

 

INLET

MOUNTING BRACKET

SPDT Ð Single-Pole, Double Throw

Fig. 35 Ð Air¯ow Switch (P/N HK06WC030)

Low-Temperature Thermostat (Fig. 36 ) Ð The optional low-temperature thermostat (LTT) is factory wired and installed. It is used to protect the chilled water coil from freezing whenever abnormally cold air passes through the coil.

The LTT consists of a 20-ft capillary tube that is serpen- tined in the airstream on the entering side of the chilled wa- ter coil. It has a range of 34 to 60 F and is factory set at 35 F.

The LTT is wired in series with the motor starter fan relay. If any 1-ft section of the capillary tube senses cold air at or below the thermostat setting, the fan shuts down. A manual reset is provided to restart the fan after the abnormal prob- lem is ®xed. The temperature setting is ®eld-adjustable.

To adjust the temperature set point, turn the adjustment screw (located on the top of the case) until the position in- dicator is at the desired temperature. (A clockwise rotation increases the set point.)

DO NOT set low-temperature thermostat below 35 F. Damage to freezestat may result.

If the temperature exceeds the set point by 5 F or more, the reset button will restore the circuit.

Outdoor-Air Thermostat (Fig. 37) Ð Also called the condensing unit status (CUST) switch, the outdoor air thermostat is a temperature-actuated switch used in systems with direct-expansion cooling. The thermostat is ®eld- installed in the outdoor condensing unit to prevent the sys- tem from operating when the outdoor-air temperature is lower

ADJUSTMENT

MANUAL RESET

SCREW

BUTTON

C F

Fig. 36 Ð Low-Temperature Thermostat

(P/N HH22CZ001)

than the condensing unit's minimum temperature. When in- stalled, the thermostat must be set to the minimum operating temperature of the condensing unit. If the condensing unit has an optional low-ambient control (Motormaster device), an outdoor-air thermostat is not required.

The outdoor-air thermostat is an SPST switch; the con- tacts open on temperature rise and the set point is adjustable from 45 to 75 F (7.2 to 23.9 C). To increase the set point, turn the indicator clockwise. See Fig. 37 for thermostat set point adjustment and mounting hole locations. Thermostat should be mounted inside condensing unit control box where it can sense the outdoor air temperature but is protected from rain and snow.

Fig. 37 Ð Outdoor-Air Thermostat (Condensing Unit

Status Switch)

48

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Image 48
Carrier 39L specifications Air¯ow Switch P/N HK06WC030

39L specifications

The Carrier 39L is a cutting-edge air conditioning unit designed for both residential and commercial applications, providing exceptional cooling and heating performance. Equipped with advanced technologies, this system ensures optimal climate control while maintaining energy efficiency.

One of the standout features of the Carrier 39L is its inverter technology. This innovation allows the system to adjust its compressor speed based on the ambient temperature, which results in a significant reduction in energy consumption. By operating at varying capacities rather than a fixed output, the 39L can maintain a consistent temperature, enhancing comfort while lowering electricity bills.

The Carrier 39L also includes a high-efficiency air filtration system, designed to capture dust, allergens, and other airborne particles. This not only improves indoor air quality but also promotes a healthier living environment. The filtration system is complemented by anti-bacterial treatment, ensuring that the air circulated within your space is both clean and refreshing.

In terms of design, the Carrier 39L boasts a sleek and compact form factor, making it easy to integrate into various settings, from homes to offices. Its quiet operation is another notable feature, as it minimizes noise levels, allowing occupants to enjoy a serene atmosphere without disruptive sound.

Further enhancing convenience, the Carrier 39L comes equipped with smart connectivity options. Users can control the unit remotely via a smartphone app, making it easy to adjust settings, program schedules, and monitor energy usage from anywhere. This feature not only improves user experience but also supports energy-saving practices.

Durability is also a key characteristic of the Carrier 39L. Constructed with high-quality materials and coated with corrosion-resistant treatments, the unit is built to withstand various environmental conditions. This ensures long-lasting performance and reduces the need for frequent maintenance.

Overall, the Carrier 39L is a versatile, efficient, and user-friendly air conditioning solution. Its blend of advanced technologies, energy-saving capabilities, and robust design makes it an ideal choice for those seeking reliable climate control in their spaces. Whether for residential comfort or commercial necessity, the Carrier 39L stands out as a leader in modern air conditioning.