IA HVAC study plan

IA HVAC · Give each week a clear focus.

8 weeks · About 7 hours per week

Week 1

HVAC Fundamentals and Psychrometrics

Define dry-bulb, wet-bulb, dew point, relative humidity, humidity ratio, and enthalpy, and state which pairs fully fix a moist-air state point.
Read psychrometric chart values for at least 12 given state points and convert between humidity ratio and relative humidity without a calculator shortcut.
Compute sensible heat ratio and identify the apparatus dew point for a simple cooling-coil process line on the chart.
Sketch and label the four basic air processes (sensible heating, sensible cooling, humidification, dehumidification) with the direction of state-point movement.

A one-page psychrometric cheat sheet plus 15 worked chart-reading problems solved with answers and units shown.

Week 2

Perform a manual block load for a single-zone space: conduction through walls, roof, and glass, plus solar, internal, infiltration, and ventilation loads.
Distinguish heating design load from cooling design load and justify why they use different outdoor design conditions.
Apply the sensible heat equation Q = 1.08 x cfm x delta-T and the latent form Q = 4.5 x cfm x delta-W to at least six load scenarios.
Estimate ventilation load using outdoor-air fraction and compare it against total coil load.
Explain how load calculation output feeds equipment selection, including safety factor and oversizing penalties.

A completed room-by-room load estimate for a sample single-story building with totals, assumptions, and a short note on oversizing risk.

Week 3

Trace the vapor-compression cycle on a pressure-enthalpy diagram and label all four components and state points.
Calculate cooling capacity, compressor power, and coefficient of performance from given enthalpy values.
Explain superheat, subcooling, and how each is measured and used as a charging and diagnostic indicator.
Compare the operating characteristics of reciprocating, scroll, and screw compressors and of air-cooled versus water-cooled condensers.
Match system type (split, packaged, chiller, VRF) to a given load profile and building constraint.

A labeled P-h diagram with a solved example cycle (capacity, power, COP) plus a one-page equipment selection comparison table.

Week 4

Size supply and return ducts using the equal-friction and velocity-reduction methods and compare the results.
Calculate friction loss, equivalent length, and available static pressure for a simple duct run.
Select grilles and diffusers to meet throw, drop, and noise criteria for a given room.
Apply the ASHRAE 62.1 ventilation-rate procedure to compute outdoor air required for a multi-zone system.
Identify causes of poor air balance and describe how to correct them.

A duct layout with sizing table, static pressure budget, and calculated outdoor-air requirement for a three-zone example.

Week 5

Compare furnace types (natural draft, induced draft, condensing) and state efficiency ranges and venting implications for each.
Compute heating output from fuel input and steady-state efficiency, and explain derating for altitude.
Describe hydronic boiler components, expansion tank sizing logic, and the role of circulators and air elimination.
Explain combustion safety checks: draft, carbon monoxide, excess air, and flue gas temperature.
Select a heat pump and explain balance point, auxiliary heat, and defrost behavior.

A heating equipment comparison matrix with efficiency, venting, and control requirements, plus three solved output and balance-point problems.

Week 6

Read a ladder diagram for a basic fan and compressor circuit and identify the control, safety, and load devices.
Explain thermostat types, deadband, staging, and proportional versus on/off control behavior.
Size overcurrent protection and conductor ampacity for a given motor using nameplate data and standard tables.
List required safety devices (high-limit, low-pressure, freeze stat, flow switch) and state what each protects.
Describe a commissioning sequence for a new rooftop unit from pre-start checks through functional performance testing.

An annotated control schematic plus a one-page commissioning checklist with acceptance criteria for each step.

Week 7

Build a troubleshooting decision tree for low suction pressure, high head pressure, and low capacity.
Interpret superheat, subcooling, delta-T, and amp draw together to isolate a fault rather than guess.
Distinguish airflow problems from refrigerant problems using measured data.
Write preventive maintenance tasks with frequencies for coils, belts, filters, drains, and safeties.
Practice documenting a fault, the evidence, and the corrective action in a service report format.

Three completed case-study diagnostics with measured readings, the fault identified, and the corrective action written as a service report.

Week 8

Summarize the scope of the key codes and standards affecting HVAC design, installation, and energy use without quoting them verbatim.
Explain how energy code requirements drive equipment efficiency minimums, economizer use, and duct insulation.
Apply economizer and outside-air control logic to a given climate and load scenario.
Review your week 2 load estimate against energy code ventilation and insulation assumptions and correct any gaps.
Complete a timed mixed-domain practice set and review every missed item to its root concept.

A two-page code and efficiency summary plus a scored 60-question mixed practice exam with a written error log.

Week 2: Can complete a single-zone cooling and heating load estimate unaided and explain each load component.

Week 4: Can size a simple duct run, produce a static pressure budget, and calculate outdoor air by procedure without notes.

Week 6: Can read a control schematic, identify safety devices, and describe a commissioning sequence from memory.

Week 8: Scores at least 75 percent on the 60-question mixed practice exam with every miss traced to a domain.