Advanced Scroll Temperature Protection Label

ADVANCED SCROLL TEMPERATURE PROTECTION (ASTP) — Advanced Scroll Temperature Protection (ASTP) is a form of internal discharge temperature protection, used in 38AUZ*12 and 38AUZ*14 units, that unloads the scroll com- pressor when the internal temperature reaches approximately 300°F. At this temperature, an internal bi-metal disk valve opens and causes the scroll elements to separate, which stops compression. Suction and discharge pressures balance while the motor continues to run. The longer the compressor runs un- loaded, the longer it must cool before the bi-metal disk resets. See Fig. 14.

		120
Time		110
		100
		90
Recommended Cooling		90
	(Minutes)	80
		70
		60
		50
		40
		30
		20
		10
		10
		0
		0	10	20	30	40	50	60	70	80	90
				Compressor Unloaded Run Time (Minutes)

*Times are approximate.

NOTE: Various factors, including high humidity, high ambient tem- perature, and the presence of a sound blanket will increase cool- down times.

Fig. 14 — Recommended Minimum Cool-Down Time

After Compressor is Stopped

To manually reset ASTP, the compressor should be stopped and allowed to cool. If the compressor is not stopped, the motor will run until the motor protector trips, which occurs up to 90 minutes later. Advanced Scroll Temperature Protection will reset automatically before the motor protector resets, which may take up to 2 hours. A label located above the terminal box identifies Copeland Scroll compressor models (ZP103 and ZP137) that contain this technology. See Fig. 15.

START UNIT — The field disconnect is closed, the indoor fan circuit breaker is closed, and the space thermostat is set above ambient so that there is no demand for cooling. Only the crankcase heater will be energized.

Reset the space thermostat below ambient so that a call for cooling is ensured.

Never charge liquid into the low-pressure side of system. Do not overcharge. During charging or removal of refriger- ant, be sure indoor-fan system is operating. Ensure both outdoor fan motors are running; bypass any Motormaster function.

ADJUST REFRIGERANT CHARGE — The unit must be charged in Cooling mode only. Refer to Cooling Charging Charts, Fig. 16 through Fig. 19. For applications with line lengths greater than 100 ft, contact Carrier representative. Vary refrigerant until the conditions of the chart are met. Note that the charging charts are different from the type normally used. The charts are based on charging the units to the correct sub- cooling for the various operating conditions. Accurate pressure gage and temperature sensing device are required. Connect the pressure gage to the service port on the liquid line service valve. Mount the temperature sensing device on the liquid line close to the liquid line service valve, and insulate it so that out- door ambient temperature does not affect the reading. Indoor airflow must be within the unit’s normal operating range. Oper- ate the unit for a minimum of 15 minutes. Ensure that pressure and temperature readings have stabilized. Plot the liquid pres- sure and temperature on chart and add or reduce the charge to meet the curve. Adjust the charge to conform with the charging chart, using the liquid pressure and temperature to read the chart.

FINAL CHECKS — Ensure that all safety controls are operating, control panel covers are on, and the service panels are in place.

Fig. 15 — Advanced Scroll Temperature

Protection Label

38AUZ specifications

The Carrier 38AUZ series is a line of air conditioning systems specifically designed to deliver optimal comfort and energy efficiency for both residential and commercial applications. Known for their advanced technology and robust performance, these units are ideal for a variety of climate conditions, ensuring consistent cooling and heating throughout the year.

One of the standout features of the Carrier 38AUZ series is its inverter technology, which allows the unit to adjust its cooling or heating output in real-time based on the ambient conditions. This results in lower energy consumption and reduced operating costs, making the system not only environmentally friendly but also budget-conscious. By minimizing temperature fluctuations, the inverter design promotes a more stable and comfortable indoor environment.

The 38AUZ units are equipped with high-efficiency compressors that enhance the system’s performance. These compressors operate quietly and efficiently, contributing to a lower noise level that is ideal for residential settings. Furthermore, they come with variable speed fan motors which offer precise airflow control, allowing users to customize their comfort level while ensuring energy savings.

In terms of build quality, the Carrier 38AUZ is constructed using durable materials designed to withstand harsh weather conditions. Its compact design allows for easy installation and maintenance, making it an ideal choice for urban environments where space is limited. Additionally, the system features a corrosion-resistant cabinet that extends its lifespan and maintains aesthetic appeal.

The 38AUZ series also includes a range of advanced control options. Users can benefit from smart technology integration, allowing for remote temperature control and scheduling through mobile devices. This feature not only enhances convenience but also provides users with complete control over their energy usage.

Moreover, the Carrier 38AUZ units come with various capacity options, catering to different space requirements. With a focus on energy efficiency, these systems often meet or exceed industry standards, including SEER ratings, ensuring optimal performance without sacrificing energy consumption.

In summary, the Carrier 38AUZ series is an exemplary choice for anyone looking to invest in a reliable, efficient, and advanced air conditioning system. With its inverter technology, high-efficiency compressors, smart control options, and durable construction, the 38AUZ not only delivers exceptional comfort but also promotes energy conservation, making it a smart choice for sustainable living.

Carrier 38AUZ appendix Advanced Scroll Temperature Protection Label

Models: 38AUZ