Introduction
This manual provides comprehensive instructions for the Goodman 15.2 SEER2 3.5-Ton 42000 BTU Central Split Unit Heat Pump AC/Heating System. It covers essential information regarding setup, operation, maintenance, troubleshooting, and detailed specifications for models GLZS4BA4210 and AMST42CU1300. Please read this manual thoroughly before installation and operation to ensure safe and efficient use of your HVAC system.

Setup and Installation
The Goodman Heat Pump AC/Heating System requires professional installation to ensure proper function, safety, and warranty validity. The system includes an outdoor condenser unit, an indoor air handler, and a comprehensive installation kit. Refer to the detailed installation instructions provided by a certified HVAC technician.
Installation Kit Components

System Dimensions

Operating Instructions
The Goodman Heat Pump system provides efficient heating and cooling for year-round comfort. Control your system using the non-programmable thermostat included in the installation kit. The heat pump functions by transferring heat, either from indoors to outdoors for cooling, or from outdoors to indoors for heating.
Understanding Heat Pump Operation
Heat pumps are designed to be highly energy-efficient, providing both heating and cooling. They operate by moving heat rather than generating it, which can lead to significant energy savings. In colder climates, a backup heat kit (such as the included 20K Backup Heat Kit) may be utilized to supplement heating when ambient temperatures are too low for the heat pump to operate efficiently on its own.
Heat Pump vs. AC Only Systems
Unlike traditional air conditioning systems that only provide cooling, a heat pump offers a year-round climate control solution. It can reverse its refrigeration cycle to either absorb heat from inside your home and release it outside (cooling) or absorb heat from outside and release it inside (heating). This dual functionality makes it a versatile and energy-efficient choice for many homeowners.
Maintenance
Regular maintenance is crucial for the longevity and efficient operation of your Goodman HVAC system. It is recommended to schedule annual professional inspections and cleanings. Between professional services, you can perform basic maintenance tasks.
Air Handler Components and Function
The air handler is a key component of your HVAC system, responsible for circulating conditioned air throughout your home. It houses the blower motor, evaporator coil, and air filter. Understanding these components is essential for proper maintenance.
Air Filter Replacement
The air filter (model ALFH1912201E, 19.5"W x 20"L) should be checked monthly and replaced every 1-3 months, depending on usage and household conditions (e.g., pets, allergies). A clean filter ensures optimal airflow and air quality.

Outdoor Unit Cleaning
Keep the area around the outdoor condenser unit clear of debris, leaves, and vegetation to ensure proper airflow. Periodically rinse the outdoor coils with a garden hose to remove dirt and dust.
Troubleshooting
If your system is not operating correctly, consider the following basic troubleshooting steps before contacting a professional:
- No Power: Check the circuit breaker for the HVAC system and the disconnect switch near the outdoor unit. Ensure the thermostat has power.
- Insufficient Heating/Cooling: Verify the thermostat settings are correct. Check the air filter for excessive dirt and replace if necessary. Ensure outdoor unit coils are clean and free of obstructions.
- Unusual Noises: Minor noises are normal during operation. However, loud or persistent unusual noises (e.g., grinding, squealing) may indicate a mechanical issue and require professional inspection.
- System Not Turning On: Confirm the thermostat is set to the desired mode (Heat/Cool) and temperature. Check for any error codes displayed on the thermostat.
For any issues beyond basic troubleshooting, or if you are unsure about a problem, contact a certified HVAC technician. Attempting complex repairs without proper training can be dangerous and may void your warranty.
Specifications
Below are the detailed specifications for the Goodman 15.2 SEER2 3.5-Ton Heat Pump AC/Heating System (Models GLZS4BA4210 / AMST42CU1300):
General System Features
- Cool/Heat Tonnage: 3.5 Ton
- Cool/Heat Output: 42,000 BTU/h
- AC Efficiency (SEER2): 14.3 - 15.2
- Heat Efficiency (HSPF2): 7.5 - 7.8
- Electrical Information: 15 Amps - 208/230 V, 1 Phase, 60 Hz
- Sound Operation: 72.0 dBA
- Equipment Weight: 262 lbs
- Condenser Stage: Single Stage
- Compressor Type: Scroll Type
- Refrigerant: R32 (TXV Device included)
- AHRI Certified and ETL Listed

Air Handler Specifications
- Blower Motor: Multi-Speed Direct Drive ECM (3/4 Horsepower and 1495 CFM)
- Evaporator Coil: All-aluminum build
- Electrical: 208/230 V, 1 Phase, 60 Hz
- Refrigerant: R32 (TXV Metering)
- Filter: ALFH1912201E (19.5"W x 20"L)
- Multi-positional: Upflow, Downflow, or Horizontal installation
- Sweat Connection: Liquid Line 3/8" (9.5 mm) ID, Suction Line 3/4" (19.0 mm) ID

Backup Heat Kit Options
- 5 KW: 16,200 BTU / 30 Amps
- 10 KW: 34,100 BTU / 60 Amps
- 15 KW: 51,150 BTU / 90 Amps
- 20 KW: 68,200 BTU / 120 Amps (Included with this system)

Energy Efficiency

Warranty and Support
Warranty Conditions
The system comes with a 10-year parts warranty when installed by a qualified technician and registered online with the manufacturer at no additional charge. Please retain your proof of purchase and installation records for warranty claims.
Customer Support
For technical assistance, service, or warranty inquiries, please contact your installing HVAC professional or the manufacturer's customer support. Ensure you have your model number (GLZS4BA4210 / AMST42CU1300) and serial number ready when contacting support.