NATE AC Service study plan
NATE AC Service · Give each week a clear focus.
8 weeks · About 6 hours per week
Air Conditioning Service
Map the NATE Air Conditioning Service task list into a personal checklist of every listed skill area, marking each as confident, shaky, or unknown
Explain the refrigeration cycle from compressor discharge through metering device, evaporator, and suction return, naming pressure and state changes at each point
Identify the four major components and the accessories (accumulator, filter-drier, muffler, service valves) on a split system and a packaged unit
Define superheat and subcooling in your own words and state what each indicates about charge and metering
Set up a study notebook with one page per task-list item for logging measured values and notes
Your checkpoint
A completed self-assessment checklist scoring every task-list item plus a hand-drawn refrigeration cycle diagram labeled with pressures, states, and component names
Air Conditioning Service
Describe the function and failure symptoms of compressors, condensers, evaporators, and metering devices (TXV, fixed orifice, capillary)
Explain how indoor and outdoor ambient conditions shift operating pressures and what normal ranges look like for common refrigerants
Differentiate R-410A, R-32, and R-454B pressure-temperature behavior and identify which require different gauges or recovery practices
Trace the electrical path from disconnect through contactor, compressor, and fan motors on a typical condensing unit
Practice reading a pressure-temperature chart to convert gauge readings into saturation temperatures
Your checkpoint
A one-page refrigerant comparison table with saturation temperatures at five pressures for each refrigerant studied, plus a labeled wiring-path sketch
Air Conditioning Service
Perform a charging workflow using superheat for fixed-orifice systems and subcooling for TXV systems, stating the target values and correction steps
Calculate target superheat from indoor wet-bulb and outdoor dry-bulb readings using a manufacturer chart
List the sequence for verifying airflow before adjusting charge and explain why airflow errors mimic charge errors
Describe how to measure static pressure and use it to diagnose duct restriction
Explain the consequences of overcharge and undercharge on compressor current, suction pressure, and superheat
Your checkpoint
A written charging procedure for both metering types, including a worked example with numbers and a decision tree for what to check first when readings are off
Air Conditioning Service
Diagnose five common no-cooling scenarios (dirty condenser, low airflow, restricted metering device, low charge, failed capacitor) from a given set of symptoms
Explain how to use a clamp meter, manifold gauges, and a thermometer set together to confirm a diagnosis
Describe the correct method for checking and adjusting refrigerant charge without venting refrigerant
Outline the steps for leak detection and evacuation to a target micron level before recharging
State the safety procedures for handling refrigerant, including PPE and cylinder storage
Your checkpoint
Five written diagnostic case studies, each with symptoms, measurements, the most likely fault, and the confirming test, scored against a self-made answer key
Air Conditioning Service
Explain the function of capacitors, contactors, relays, thermostats, and pressure switches in an AC circuit
Read a ladder schematic and identify where to place meter probes to test each component
Describe how to test a run capacitor and a dual capacitor safely, including discharge procedure
Explain how to check compressor windings for opens, shorts, and grounds
Describe blower motor types (PSC, ECM, variable-speed) and how each is diagnosed differently
Your checkpoint
A component-by-component test sheet listing the meter setting, expected reading, and failure reading for at least eight electrical components
Air Conditioning Service
Explain the role of airflow in capacity, efficiency, and equipment life, including target CFM per ton
Describe how to measure external static pressure and total airflow using a flow hood or pressure-based method
Identify duct design faults (undersized returns, excessive flex runs, sharp transitions) and their symptoms
Explain how to balance airflow between rooms and when to recommend duct modifications
Describe indoor air quality accessories (filters, UV, humidifiers) and how each affects airflow and service
Your checkpoint
An airflow audit worksheet with static pressure readings, a CFM estimate, and a written recommendation for at least one duct correction
Air Conditioning Service
Walk through a complete preventive maintenance visit in order, from thermostat check to final readings
List the measurements to record at every maintenance visit and the acceptable ranges for each
Explain heat pump heating-mode checks (defrost cycle, reversing valve, auxiliary heat) at a level sufficient for AC service calls
Describe how to document a service call so a second technician can repeat the diagnosis
Practice explaining a repair recommendation to a customer in plain language
Your checkpoint
A complete maintenance checklist with measurement fields and acceptable ranges, plus a one-page sample service report written as if for a real customer
Air Conditioning Service
Review every task-list item marked shaky or unknown in week one and re-test yourself on each
Complete timed practice sets covering the full domain and score them
Re-derive superheat and subcooling targets from charts without notes
Recite the safety and refrigerant-handling rules from memory
Plan the exam-day logistics and confirm which credentials and prerequisites apply to your certification path
Your checkpoint
A scored full-length practice result with a written list of remaining weak areas and a remediation plan for each
Milestones
Week 2: Can draw the refrigeration cycle and label all four components, states, and pressures without notes, and can convert gauge pressure to saturation temperature for R-410A on five readings
Week 4: Scores at least 80 percent on the five diagnostic case studies and can state the correct charging method for fixed-orifice versus TXV systems without reference
Week 6: Can identify probe placement for eight electrical components from a schematic and can calculate target CFM for a given system size
Week 8: Scores at least 85 percent on a timed full-domain practice set and has zero task-list items still marked unknown