MS HVAC study plan
MS HVAC · Give each week a clear focus.
8 weeks · About 6 hours per week
HVACR Core Knowledge and Skills
Define and correctly apply the core thermodynamics terms used across the exam: sensible heat, latent heat, superheat, subcooling, enthalpy, and saturation.
Convert between Fahrenheit, Celsius, PSIG, PSIA, and absolute temperature without a reference sheet, showing unit labels at each step.
Interpret a standard pressure-enthalpy diagram well enough to locate the four basic cycle points for a simple vapor-compression system.
Explain the function of each major HVACR system component (compressor, condenser, metering device, evaporator) in plain language.
Your checkpoint
A one-page handwritten conversion and formula sheet (temperature, pressure, superheat/subcooling, airflow equations) solved cold with no notes, scored at 90% or better on a 20-item self-quiz.
Refrigeration Systems and Components
Trace refrigerant flow through a vapor-compression circuit and state the phase and pressure at each of the four points.
Calculate superheat and subcooling from gauge and line temperatures for both a fixed-orifice and a TXV system.
Identify the symptoms of common faults (undercharge, overcharge, restricted filter-drier, non-condensables) on the pressure-enthalpy diagram.
Describe safe refrigerant handling, recovery, and evacuation practices to the level of EPA Section 608 concepts.
Your checkpoint
A completed fault-diagnosis chart listing at least six refrigerant-side faults with the expected suction pressure, head pressure, superheat, and subcooling signature for each.
Refrigeration Systems and Components & HVACR Core Knowledge and Skills
Compare compressor types (reciprocating, scroll, screw, rotary) by application, capacity range, and common failure modes.
Explain how each metering device type (capillary tube, fixed orifice, TXV, EEV) responds to changing load and ambient conditions.
Size and select evaporator/condenser coils using approach temperature and airflow assumptions, and justify the selection.
Diagnose a system that is running but not cooling using a structured sequence: airflow, charge, then refrigerant-side restriction.
Your checkpoint
A written case diagnosis of two instructor-style scenarios (one low-superheat, one high-superheat) with the recommended corrective action and the reasoning behind each step.
Electrical Systems and Controls
Read a ladder diagram and a wiring schematic and trace a call for cooling from thermostat through contactor to compressor.
Apply Ohm's law and the power equation to compute current, voltage drop, and resistance in a control and load circuit.
Test capacitors, contactors, relays, and thermistors with a multimeter and state the pass/fail criteria for each.
Explain the role of safeties (high/low pressure switches, overloads, freeze stats) and how each interrupts the circuit.
Your checkpoint
A redrawn ladder diagram of a basic residential cooling circuit with every component labeled and a measured-versus-expected value table for a live or simulated test.
Electrical Systems and Controls & Heating Systems and System Performance
Differentiate line-voltage from low-voltage control wiring and identify code-relevant installation requirements for each.
Describe how a heat pump defrost control, reversing valve, and auxiliary heat staging interact during a heating call.
Calculate electric-resistance heat capacity in kW and BTUH and verify it against nameplate data.
Diagnose a no-heat call on a heat pump by isolating the thermostat, control board, and outdoor unit in sequence.
Your checkpoint
A troubleshooting flowchart for a heat pump no-heat complaint with at least eight decision points and the expected reading at each test location.
Air Distribution, Ductwork, and Indoor Air Quality
Apply the sensible heat equation to compute required airflow from load, temperature rise, and CFM relationships.
Measure external static pressure and use a fan performance table to determine delivered CFM.
Size and lay out a simple trunk-and-branch duct system, accounting for friction loss and equivalent length of fittings.
Identify the causes and corrections for common duct defects: leakage, undersized returns, excessive flex sag, and poor transitions.
Your checkpoint
A duct layout sketch for a single-zone system with a static pressure budget and a calculated CFM at each branch, checked against a fan curve.
Air Distribution, Ductwork, and Indoor Air Quality & Heating Systems and System Performance
Explain the three pillars of indoor air quality (source control, ventilation, filtration) and how each is applied in a residential retrofit.
Interpret MERV ratings and select filtration appropriate to a given equipment static pressure limit.
Compute combustion air requirements and identify venting and draft problems on a natural-gas furnace.
Measure temperature rise across a furnace and compare it to the nameplate range to judge airflow and combustion adequacy.
Your checkpoint
A combustion-analysis and airflow verification report for one furnace scenario, including temperature rise, expected versus measured, and a written recommendation.
HVACR Core Knowledge and Skills & Refrigeration Systems and Components & Electrical Systems and Controls & Air Distribution, Ductwork, and Indoor Air Quality & Heating Systems and System Performance
Integrate all five domains by diagnosing two full-system scenarios that combine refrigerant, electrical, airflow, and heating faults.
Complete timed practice sets under exam conditions to build pacing and reduce careless errors.
Review every missed item from weeks 1 through 7 and restate the underlying principle in your own words.
Confirm readiness by scoring consistently above the target threshold on mixed-domain practice.
Your checkpoint
Two full-length timed practice exams completed with a written error log; every missed question corrected with the governing principle and the reference source.
Milestones
Week 2: Score 80% or better on a 25-item mixed quiz covering domains 1 and 2, and correctly compute superheat and subcooling for four sample systems without notes.
Week 4: Trace a cooling call through a ladder diagram end-to-end in under five minutes and correctly identify the fault in three of four injected electrical scenarios.
Week 6: Compute required CFM from a given load and temperature difference and match it to within 10% of the value derived from a fan performance table.
Week 8: Achieve the target passing score on two consecutive timed full-length practice exams, with no domain scoring below 70%.