Content Outline
Official CSLB document detailing exam sections and weightings.
Getting Started: Navigating the C-20 Exam
Free knowledge base
CSLB C-20 HVAC Contractor — key terms, tricks & tips
Everything from the course in one searchable place: 272 entries. Use it to review before a practice test or look up a word you forgot.
272 results
Multiple-choice
Question format with one correct answer out of several options.
Getting Started: Navigating the C-20 Exam
Passing Score
Minimum percentage (70%) required to pass the CSLB exam.
Getting Started: Navigating the C-20 Exam
Weighted Sections
Exam sections with different numbers of questions or importance.
Getting Started: Navigating the C-20 Exam
Test Proctor
Person supervising the exam at the testing center.
Getting Started: Navigating the C-20 Exam
Computer-based testing
Exams administered digitally at a testing facility.
Getting Started: Navigating the C-20 Exam
Understanding the CSLB C-20 Exam Structure
To remember the key exam areas, think: 'PlaFfS CoSa'. Planning, Fabrication, Service, Code, Safety.
Getting Started: Navigating the C-20 Exam
Understanding the CSLB C-20 Exam Structure
The CSLB provides a free 'Candidate Information Bulletin' for each trade, which includes the detailed Content Outline for the C-20 exam. Always download the most current version directly from the CSLB website (cslb.ca.gov) to ensure you are studying the correct material and weightings.
Getting Started: Navigating the C-20 Exam
Understanding the CSLB C-20 Exam Structure
Studying all topics equally, instead of focusing more on heavily weighted sections.
Getting Started: Navigating the C-20 Exam
Understanding the CSLB C-20 Exam Structure
Not checking the official CSLB Content Outline for the most current exam breakdown.
Getting Started: Navigating the C-20 Exam
Understanding the CSLB C-20 Exam Structure
Failing to practice time management during practice exams, leading to running out of time on the actual test.
Getting Started: Navigating the C-20 Exam
Candidate Information Bulletin (CIB)
Official CSLB document outlining exam content and structure.
Getting Started: Navigating the C-20 Exam
Active Learning
Engaging with material through summarizing, teaching, or problem-solving.
Getting Started: Navigating the C-20 Exam
Practice Tests
Simulated exams used to assess knowledge and identify weaknesses.
Getting Started: Navigating the C-20 Exam
California Mechanical Code (CMC)
State-specific regulations for mechanical systems, including HVAC.
Getting Started: Navigating the C-20 Exam
Title 24
California's energy efficiency standards for buildings.
Getting Started: Navigating the C-20 Exam
EPA Section 608
Federal regulations for refrigerant handling and technician certification.
Getting Started: Navigating the C-20 Exam
Study Schedule
A planned timetable for allocating time to study topics.
Getting Started: Navigating the C-20 Exam
Effective Study Strategies for C-20 Success
To remember key study steps: 'PLAN' - **P**ractice, **L**earn Actively, **A**ssess, **N**avigate Resources.
Getting Started: Navigating the C-20 Exam
Effective Study Strategies for C-20 Success
The CSLB C-20 exam heavily emphasizes the California Mechanical Code (CMC) and Title 24 energy efficiency standards. Be prepared to interpret and apply code requirements, not just memorize them. Keywords like 'per CMC' or 'Title 24 compliant' are common.
Getting Started: Navigating the C-20 Exam
Effective Study Strategies for C-20 Success
Only reading the textbook passively without testing knowledge.
Getting Started: Navigating the C-20 Exam
Effective Study Strategies for C-20 Success
Neglecting the Business and Law section, assuming trade knowledge is enough.
Getting Started: Navigating the C-20 Exam
Effective Study Strategies for C-20 Success
Cramming at the last minute instead of consistent, spaced-out study.
Getting Started: Navigating the C-20 Exam
Manual J
ACCA standard for residential heating/cooling load calculations.
Planning & Layout Essentials
Load Calculation
Determining heat gain/loss for HVAC system sizing.
Planning & Layout Essentials
BTUh
British Thermal Units per hour; unit of heating/cooling capacity.
Planning & Layout Essentials
Short-cycling
HVAC system turning on/off too frequently.
Planning & Layout Essentials
Infiltration
Uncontrolled air leakage into/out of a building.
Planning & Layout Essentials
U-value
Rate of heat transfer through a material; lower is better.
Planning & Layout Essentials
SHGC
Solar Heat Gain Coefficient; solar radiation passing through glass.
Planning & Layout Essentials
Design Temperature
Extreme outdoor temperatures used for load calculations.
Planning & Layout Essentials
Load Calculations: Manual J Concepts
LOADS of factors: L-Location (climate), O-Orientation (sun), A-Air leakage, D-Dimensions (size), S-Stuff inside (occupants/appliances).
Planning & Layout Essentials
Load Calculations: Manual J Concepts
The CSLB exam emphasizes that Manual J is the industry standard for residential load calculations. Be prepared for questions about what factors influence heat gain/loss, especially related to California's diverse climate zones and Title 24 energy efficiency requirements for insulation and window performance.
Planning & Layout Essentials
Load Calculations: Manual J Concepts
Relying on rules-of-thumb (e.g., X BTUh per square foot) instead of detailed calculations.
Planning & Layout Essentials
Load Calculations: Manual J Concepts
Ignoring internal heat gains from occupants, lighting, or appliances.
Planning & Layout Essentials
Load Calculations: Manual J Concepts
Failing to account for specific window types, shading, or building orientation.
Planning & Layout Essentials
Manual D
ACCA standard for residential duct system design.
Planning & Layout Essentials
CFM
Cubic Feet per Minute; unit of airflow.
Planning & Layout Essentials
Static Pressure
Resistance to airflow in a duct system.
Planning & Layout Essentials
Plenum
Main air distribution box connected to the air handler.
Planning & Layout Essentials
Register
Grille with a damper for supply air into a room.
Planning & Layout Essentials
Grille
Cover for an air opening, typically for return air.
Planning & Layout Essentials
Friction Loss
Pressure drop due to air rubbing against duct surfaces.
Planning & Layout Essentials
Dampers
Adjustable plates to control or balance airflow.
Planning & Layout Essentials
Duct Design Principles: Manual D
Ducts Deliver. Manual D is for Ductwork, ensuring air is Delivered correctly.
Planning & Layout Essentials
Duct Design Principles: Manual D
The CSLB exam frequently tests on the *purpose* of Manual D and its relationship to Manual J. Memorize that Manual J determines the *load* (CFM needed) and Manual D designs the *ducts* to deliver that CFM. Also, be aware that Title 24 energy standards often require compliance with ACCA Manuals.
Planning & Layout Essentials
Duct Design Principles: Manual D
Ignoring Manual D and guessing duct sizes, leading to imbalanced airflow and comfort issues.
Planning & Layout Essentials
Duct Design Principles: Manual D
Not accounting for the cumulative effect of all duct fittings (elbows, transitions) on total static pressure.
Planning & Layout Essentials
Duct Design Principles: Manual D
Using flexible ductwork excessively or improperly, which significantly increases friction loss compared to rigid duct.
Planning & Layout Essentials
Short Cycling
HVAC system turning on/off too frequently, reducing efficiency.
Planning & Layout Essentials
SEER
Seasonal Energy Efficiency Ratio; measures AC cooling efficiency.
Planning & Layout Essentials
AFUE
Annual Fuel Utilization Efficiency; measures furnace heating efficiency.
Planning & Layout Essentials
HSPF
Heating Seasonal Performance Factor; measures heat pump heating efficiency.
Planning & Layout Essentials
AHRI Certified
Indicates matched HVAC components meet performance standards.
Planning & Layout Essentials
Split System
HVAC with separate indoor and outdoor units.
Planning & Layout Essentials
Package Unit
HVAC with all components in a single outdoor cabinet.
Planning & Layout Essentials
Equipment Sizing and Selection
To remember the efficiency ratings: 'SEER' for Summer (cooling), 'AFUE' for Furnace (heating), 'HSPF' for Heat Pump (heating).
Planning & Layout Essentials
Equipment Sizing and Selection
The CSLB exam frequently tests on minimum efficiency standards for HVAC equipment as per Title 24. Be prepared to identify the meaning of SEER, AFUE, and HSPF, and understand why these ratings are crucial for compliance in California.
Planning & Layout Essentials
Equipment Sizing and Selection
Replacing old equipment with the same size without performing a new load calculation.
Planning & Layout Essentials
Equipment Sizing and Selection
Ignoring AHRI certification for matched split systems, leading to reduced efficiency.
Planning & Layout Essentials
Equipment Sizing and Selection
Not considering future building modifications (e.g., additions) when sizing new equipment.
Planning & Layout Essentials
Blueprint
Graphical construction drawings showing building plans and system layouts.
Planning & Layout Essentials
Specifications
Written documents detailing materials, quality, and installation requirements.
Planning & Layout Essentials
Legend
A key on a blueprint explaining the meaning of symbols and line types.
Planning & Layout Essentials
CSI MasterFormat
A standardized system for organizing construction specifications into divisions.
Planning & Layout Essentials
Mechanical Drawings
Blueprints specifically depicting HVAC, plumbing, and fire protection systems.
Planning & Layout Essentials
Architectural Drawings
Blueprints showing building layout, dimensions, and aesthetic features.
Planning & Layout Essentials
Structural Drawings
Blueprints detailing the building's framework, beams, and foundations.
Planning & Layout Essentials
R-value
A measure of thermal resistance, indicating insulation effectiveness.
Planning & Layout Essentials
Interpreting Blueprints and Specifications
To remember the difference: BluePrints are the 'Picture,' SpeciFications are the 'Fine Print.'
Planning & Layout Essentials
Interpreting Blueprints and Specifications
The CSLB C-20 exam will test your ability to interpret common HVAC symbols and understand the relationship between blueprints and specifications. Pay close attention to questions about duct sizing, equipment location, and material requirements as specified in project documents. Remember that specifications often contain more detailed and binding requirements than general notes on drawings.
Planning & Layout Essentials
Interpreting Blueprints and Specifications
Only reviewing mechanical drawings and ignoring architectural or structural plans, leading to conflicts.
Planning & Layout Essentials
Interpreting Blueprints and Specifications
Skimming specifications instead of reading them thoroughly, missing critical material or installation requirements.
Planning & Layout Essentials
Interpreting Blueprints and Specifications
Assuming a symbol's meaning without checking the drawing legend, leading to incorrect component identification.
Planning & Layout Essentials
Gas Furnace
Appliance that heats air by burning natural gas or propane for distribution.
Heating Systems Fundamentals
Heat Exchanger
Component separating combustion gases from indoor air, transferring heat.
Heating Systems Fundamentals
Blower Motor
Fan that circulates air through the furnace and ductwork.
Heating Systems Fundamentals
Igniter
Device that lights the gas at the burners in a furnace.
Heating Systems Fundamentals
Limit Switch
Safety control that shuts off the burner if the furnace overheats.
Heating Systems Fundamentals
Flame Sensor
Safety device that confirms the presence of a flame.
Heating Systems Fundamentals
Carbon Monoxide
Colorless, odorless, toxic gas, a byproduct of incomplete combustion.
Heating Systems Fundamentals
Gas Furnaces and Heat Exchangers
Imagine a 'Hot Ex-Girlfriend' (Heat Exchanger) who keeps the 'Toxic Ex-Boyfriend' (Combustion Gases) separate from 'You' (Indoor Air) for your safety!
Heating Systems Fundamentals
Gas Furnaces and Heat Exchangers
The CSLB C-20 exam frequently tests on the safety aspects of gas furnaces, particularly regarding heat exchanger integrity and carbon monoxide. Memorize the function of the limit switch, flame sensor, and pressure switch. Understand that a cracked heat exchanger is a critical safety issue requiring immediate action.
Heating Systems Fundamentals
Gas Furnaces and Heat Exchangers
Ignoring faint odors or discoloration around the furnace, which can be signs of a heat exchanger issue.
Heating Systems Fundamentals
Gas Furnaces and Heat Exchangers
Attempting to patch a cracked heat exchanger instead of recommending full replacement.
Heating Systems Fundamentals
Gas Furnaces and Heat Exchangers
Not checking for proper carbon monoxide levels during furnace maintenance or after repairs.
Heating Systems Fundamentals
Combustion Air
Air supplied for complete burning of fuel.
Heating Systems Fundamentals
Backdrafting
Reverse flow of combustion gases into living space.
Heating Systems Fundamentals
Vent Static Pressure
Pressure inside the vent system during operation.
Heating Systems Fundamentals
Dew Point
Temperature at which water vapor condenses.
Heating Systems Fundamentals
Category I Vent
Non-positive pressure, above dew point flue gas.
Heating Systems Fundamentals
Category IV Vent
Positive pressure, below dew point flue gas, requires condensate drain.
Heating Systems Fundamentals
Flue Gas
Products of combustion exhausted through the vent.
Heating Systems Fundamentals
Combustion Air and Venting Categories
To remember Venting Categories: 'I'm Hot, II'm Cool, III'm Pushed, IV'm Pushed and Cool.' (Hot = above dew point, Cool = below dew point, Pushed = positive pressure).
Heating Systems Fundamentals
Combustion Air and Venting Categories
The California Mechanical Code (CMC) is the primary reference for combustion air and venting requirements. Pay close attention to sections regarding minimum free area for combustion air openings, clearances to combustibles, and vent termination locations. Title 24 energy standards also influence the efficiency of venting systems.
Heating Systems Fundamentals
Combustion Air and Venting Categories
Under-sizing combustion air openings, leading to incomplete combustion and CO production.
Heating Systems Fundamentals
Combustion Air and Venting Categories
Using incorrect vent material for the appliance's category, causing heat damage or condensation issues.
Heating Systems Fundamentals
Combustion Air and Venting Categories
Improperly terminating vents too close to windows or air intakes, allowing exhaust gases to re-enter the building.
Heating Systems Fundamentals
Reversing Valve
Component that switches refrigerant flow for heating/cooling.
Heating Systems Fundamentals
Defrost Cycle
Process to melt ice from outdoor coil during heating.
Heating Systems Fundamentals
Coefficient of Performance (COP)
Ratio of heating/cooling output to energy input.
Heating Systems Fundamentals
Auxiliary Heat
Supplemental electric resistance heat for cold conditions.
Heating Systems Fundamentals
Air-Source Heat Pump
Extracts/rejects heat from/to ambient air.
Heating Systems Fundamentals
Geothermal Heat Pump
Uses stable ground temperature for heat exchange.
Heating Systems Fundamentals
Heat Pumps: Operation and Applications
To remember the heat pump cycle: 'Cold OUT, Compressor HOT, Reverse IN, Warm HOME, Expand COLD.'
Heating Systems Fundamentals
Heat Pumps: Operation and Applications
California's Title 24 Energy Code heavily promotes heat pump technology due to its energy efficiency. Expect questions on SEER (Seasonal Energy Efficiency Ratio), EER (Energy Efficiency Ratio), and HSPF (Heating Seasonal Performance Factor) ratings, and how they relate to compliance.
Heating Systems Fundamentals
Heat Pumps: Operation and Applications
Assuming a heat pump only provides heating; it provides both heating and cooling.
Heating Systems Fundamentals
Heat Pumps: Operation and Applications
Ignoring the importance of the defrost cycle in cold weather, leading to efficiency loss or damage.
Heating Systems Fundamentals
Heat Pumps: Operation and Applications
Not understanding that auxiliary heat is normal and necessary in very cold conditions for heat pumps.
Heating Systems Fundamentals
Hydronic Heating
Heating system using water or fluid to transfer heat.
Heating Systems Fundamentals
Boiler
Device that heats water for a hydronic system.
Heating Systems Fundamentals
Circulator Pump
Component that moves water through the piping.
Heating Systems Fundamentals
Expansion Tank
Manages water volume changes due to temperature.
Heating Systems Fundamentals
Terminal Unit
Component that emits heat into the conditioned space.
Heating Systems Fundamentals
Closed System
Sealed hydronic system, not exposed to atmosphere.
Heating Systems Fundamentals
Radiant Heating
Heat transfer via electromagnetic waves from a warm surface.
Heating Systems Fundamentals
Basic Hydronic Heating Systems
To remember hydronic components: 'B-C-P-E-A-T-R' - Boiler, Circulator, Pipes, Expansion, Air, Terminal, Return. Or, think 'Hot Water Runs Through Pipes Efficiently And To Rooms'.
Heating Systems Fundamentals
Basic Hydronic Heating Systems
The CSLB exam may ask about Title 24 energy efficiency requirements for hydronic systems, particularly regarding pump sizing, insulation, and controls. Memorize the basic function of each major component.
Heating Systems Fundamentals
Basic Hydronic Heating Systems
Confusing hydronic systems with forced-air systems; hydronic uses water, forced-air uses air.
Heating Systems Fundamentals
Basic Hydronic Heating Systems
Ignoring the importance of air elimination in hydronic systems; trapped air causes cold spots and inefficiency.
Heating Systems Fundamentals
Basic Hydronic Heating Systems
Underestimating the role of the expansion tank; it's not just a storage tank, it's a pressure regulator.
Heating Systems Fundamentals
Refrigerant
A substance that readily absorbs and releases heat during phase changes.
Cooling & Refrigeration Mastery
Compressor
Pumps refrigerant, increasing its pressure and temperature.
Cooling & Refrigeration Mastery
Condenser
Releases heat from refrigerant, causing it to condense into a liquid.
Cooling & Refrigeration Mastery
Metering Device
Reduces refrigerant pressure and temperature before the evaporator.
Cooling & Refrigeration Mastery
Evaporator
Absorbs heat from the conditioned space, causing refrigerant to vaporize.
Cooling & Refrigeration Mastery
Latent Heat
Heat absorbed or released during a phase change without temperature change.
Cooling & Refrigeration Mastery
High-Pressure Side
Portion of system from compressor outlet to metering device inlet.
Cooling & Refrigeration Mastery
Low-Pressure Side
Portion of system from metering device outlet to compressor inlet.
Cooling & Refrigeration Mastery
The Refrigeration Cycle Explained
Compressor, Condenser, Metering Device, Evaporator: 'Can Coolers Make Everything Easy?'
Cooling & Refrigeration Mastery
The Refrigeration Cycle Explained
The CSLB exam frequently asks about the state of the refrigerant (liquid/vapor, high/low pressure/temperature) at specific points in the cycle, especially entering and leaving each major component. Memorize the phase and pressure/temperature changes at each step.
Cooling & Refrigeration Mastery
The Refrigeration Cycle Explained
Confusing the roles of the condenser and evaporator, especially which one absorbs heat and which rejects it.
Cooling & Refrigeration Mastery
The Refrigeration Cycle Explained
Incorrectly identifying the refrigerant's state (liquid vs. vapor, high vs. low pressure/temperature) at different points.
Cooling & Refrigeration Mastery
The Refrigeration Cycle Explained
Forgetting that the compressor handles vapor, not liquid, and that liquid refrigerant entering the compressor can cause damage.
Cooling & Refrigeration Mastery
Superheat
Heat absorbed by vapor after evaporation.
Cooling & Refrigeration Mastery
Subcooling
Heat removed from liquid after condensation.
Cooling & Refrigeration Mastery
Saturation Temperature
Temperature at which a substance changes phase.
Cooling & Refrigeration Mastery
P/T Chart
Pressure-temperature chart for refrigerants.
Cooling & Refrigeration Mastery
Fixed Orifice
Metering device, charges by superheat.
Cooling & Refrigeration Mastery
TXV
Thermostatic Expansion Valve, charges by subcooling.
Cooling & Refrigeration Mastery
Flash Gas
Vapor in liquid line before metering device.
Cooling & Refrigeration Mastery
Superheat, Subcooling, and System Charging
Remember 'Superheat is for Suction, Subcooling is for Sliquid (Liquid)'. Both start with 'S' and relate to the 'S'ides of the system.
Cooling & Refrigeration Mastery
Superheat, Subcooling, and System Charging
The CSLB C-20 exam will test your ability to interpret P/T charts and apply superheat/subcooling calculations. Pay close attention to refrigerant types (e.g., R-410A, R-22) and their corresponding pressure-temperature relationships. Memorize the definitions and the impact of incorrect values.
Cooling & Refrigeration Mastery
Superheat, Subcooling, and System Charging
Confusing superheat and subcooling definitions or their measurement points.
Cooling & Refrigeration Mastery
Superheat, Subcooling, and System Charging
Using the wrong P/T chart for the specific refrigerant in the system.
Cooling & Refrigeration Mastery
Superheat, Subcooling, and System Charging
Adjusting refrigerant charge without considering both superheat and subcooling, or manufacturer's target values.
Cooling & Refrigeration Mastery
Superheat, Subcooling, and System Charging
Not allowing the system to stabilize before taking final readings.
Cooling & Refrigeration Mastery
CFC
Chlorofluorocarbon; high ODP, phased out.
Cooling & Refrigeration Mastery
HCFC
Hydrochlorofluorocarbon; high ODP, being phased out.
Cooling & Refrigeration Mastery
HFC
Hydrofluorocarbon; zero ODP, high GWP, phasedown.
Cooling & Refrigeration Mastery
ODP
Ozone Depletion Potential; measure of harm to ozone.
Cooling & Refrigeration Mastery
GWP
Global Warming Potential; measure of climate impact.
Cooling & Refrigeration Mastery
EPA 608
Certification for refrigerant handling in the US.
Cooling & Refrigeration Mastery
Recovery
Removing refrigerant from a system into a container.
Cooling & Refrigeration Mastery
Refrigerants and EPA 608 Certification
To remember the order of refrigerant phase-outs: 'CFCs Came First, HCFCs Came Next, HFCs Have a Future (but are Phasing Down).'
Cooling & Refrigeration Mastery
Refrigerants and EPA 608 Certification
The CSLB C-20 exam will test your knowledge of EPA 608 regulations, particularly the prohibition against venting refrigerants and the requirements for certification types (Type I, II, III, Universal). Know the difference between ODP and GWP and which refrigerant types are associated with each.
Cooling & Refrigeration Mastery
Refrigerants and EPA 608 Certification
Venting refrigerants into the atmosphere instead of recovering them.
Cooling & Refrigeration Mastery
Refrigerants and EPA 608 Certification
Not verifying refrigerant type before adding to a system, leading to contamination.
Cooling & Refrigeration Mastery
Refrigerants and EPA 608 Certification
Working on refrigerant-containing systems without proper EPA 608 certification.
Cooling & Refrigeration Mastery
Reciprocating Compressor
Uses pistons to compress refrigerant vapor.
Cooling & Refrigeration Mastery
Scroll Compressor
Uses two interleaved scrolls for efficient compression.
Cooling & Refrigeration Mastery
Capillary Tube
A fixed-orifice metering device, simple and inexpensive.
Cooling & Refrigeration Mastery
TXV (Thermostatic Expansion Valve)
Adjusts refrigerant flow based on evaporator superheat.
Cooling & Refrigeration Mastery
EEV (Electronic Expansion Valve)
Precisely controls refrigerant flow using electronic signals.
Cooling & Refrigeration Mastery
Compressors and Metering Devices
To remember the compressor's job: 'Compressor Crushes Coolant' – it crushes the low-pressure coolant to make it hot and high-pressure!
Cooling & Refrigeration Mastery
Compressors and Metering Devices
The CSLB C-20 exam frequently tests on the function of TXVs and EEVs, particularly their role in maintaining superheat and system efficiency. Be ready to distinguish between fixed-orifice and thermostatic/electronic devices. Also, understand Title 24 implications for high-efficiency compressors and EEVs in new installations.
Cooling & Refrigeration Mastery
Compressors and Metering Devices
Confusing the function of the compressor with the condenser (compressor adds pressure, condenser removes heat).
Cooling & Refrigeration Mastery
Compressors and Metering Devices
Believing all metering devices respond to system load (only TXVs and EEVs do).
Cooling & Refrigeration Mastery
Compressors and Metering Devices
Ignoring superheat readings when troubleshooting metering device issues.
Cooling & Refrigeration Mastery
SEER2
Seasonal Energy Efficiency Ratio 2; cooling efficiency over a season.
Cooling & Refrigeration Mastery
EER
Energy Efficiency Ratio; cooling efficiency at peak conditions.
Cooling & Refrigeration Mastery
DOE
Department of Energy; sets federal efficiency standards.
Cooling & Refrigeration Mastery
CEC
California Energy Commission; sets state efficiency standards.
Cooling & Refrigeration Mastery
SEER2, EER, and Energy Efficiency Ratings
SEER2 is for Summer, EER for Extreme, HSPF for Heat Pump. Remember the 'S' for Seasonal, 'E' for Extreme, 'H' for Heating.
Cooling & Refrigeration Mastery
SEER2, EER, and Energy Efficiency Ratings
Memorize the current minimum SEER2, EER, and HSPF2 requirements for residential split systems in California, as these are frequently tested. Pay attention to regional variations for SEER2.
Cooling & Refrigeration Mastery
SEER2, EER, and Energy Efficiency Ratings
Confusing SEER2 with EER: SEER2 is seasonal average, EER is peak performance.
Cooling & Refrigeration Mastery
SEER2, EER, and Energy Efficiency Ratings
Not knowing the current minimum efficiency standards for California's Title 24.
Cooling & Refrigeration Mastery
SEER2, EER, and Energy Efficiency Ratings
Failing to account for regional differences in minimum SEER2 requirements.
Cooling & Refrigeration Mastery
Inches of Water Column
Standard unit for measuring static pressure.
Ventilation & Air Distribution
Airflow Dynamics
Study of how air moves through a system.
Ventilation & Air Distribution
Pressure Drop
Reduction in pressure due to friction or resistance.
Ventilation & Air Distribution
Turbulence
Irregular, chaotic air movement, increasing resistance.
Ventilation & Air Distribution
Laminar Flow
Smooth, orderly air movement with minimal resistance.
Ventilation & Air Distribution
CFM, Static Pressure, and Airflow Dynamics
Think 'CFM is how much, Static is how hard.' CFM is the volume of air, static pressure is the 'push' needed to get it through the system.
Ventilation & Air Distribution
CFM, Static Pressure, and Airflow Dynamics
The CSLB exam often asks about the relationship between static pressure and airflow, and how duct design impacts system performance. Memorize that high static pressure restricts CFM. Also, be aware of Title 24 requirements for duct sealing and sizing to minimize static pressure losses and improve energy efficiency.
Ventilation & Air Distribution
CFM, Static Pressure, and Airflow Dynamics
Ignoring static pressure when troubleshooting low airflow, focusing only on fan speed.
Ventilation & Air Distribution
CFM, Static Pressure, and Airflow Dynamics
Assuming all duct runs of the same length have the same pressure drop.
Ventilation & Air Distribution
CFM, Static Pressure, and Airflow Dynamics
Failing to account for filter and coil resistance in static pressure calculations.
Ventilation & Air Distribution
Mastic
A thick, paste-like sealant used for durable, airtight duct connections.
Ventilation & Air Distribution
UL 181
Underwriters Laboratories standard for duct and closure materials.
Ventilation & Air Distribution
Duct Leakage Test
A diagnostic procedure to measure air loss from a duct system.
Ventilation & Air Distribution
Duct Blaster
Equipment used to pressurize ducts and measure air leakage.
Ventilation & Air Distribution
HERS Rater
Home Energy Rating System rater, certified to perform energy code verifications.
Ventilation & Air Distribution
Duct Sealing, Testing, and Efficiency
Think 'Seal It Tight, Save the Light!' – Sealing ducts tightly saves energy (light bill) and ensures comfort.
Ventilation & Air Distribution
Duct Sealing, Testing, and Efficiency
The C-20 exam will heavily emphasize Title 24 requirements for duct sealing and leakage testing. Know the typical maximum allowable leakage rates (e.g., 6% of nominal airflow at 25 Pascals for ducts outside conditioned space) and the role of a HERS Rater in verification.
Ventilation & Air Distribution
Duct Sealing, Testing, and Efficiency
Using unapproved tapes (like cloth-backed duct tape) for sealing, which degrade quickly and fail.
Ventilation & Air Distribution
Duct Sealing, Testing, and Efficiency
Not cleaning surfaces before applying mastic or tape, leading to poor adhesion and premature failure.
Ventilation & Air Distribution
Duct Sealing, Testing, and Efficiency
Neglecting to seal all connections, including plenum connections, take-offs, and return air pathways.
Ventilation & Air Distribution
MERV
Minimum Efficiency Reporting Value; filter efficiency rating.
Ventilation & Air Distribution
IAQ
Indoor Air Quality; air health inside buildings.
Ventilation & Air Distribution
Pleated Filter
Filter with folds for increased surface area.
Ventilation & Air Distribution
HEPA Filter
High-Efficiency Particulate Air; captures tiny particles.
Ventilation & Air Distribution
Micron
Unit of measurement for small particles.
Ventilation & Air Distribution
Adsorption
Process of gas/liquid molecules adhering to a surface.
Ventilation & Air Distribution
Filtration: MERV Ratings and IAQ
MERV: M is for 'Most' particles, E is for 'Efficiently' removed, R is for 'Rating' the filter, V is for 'Value' to your health.
Ventilation & Air Distribution
Filtration: MERV Ratings and IAQ
The CSLB exam frequently tests on the implications of MERV ratings for different applications. Remember that higher MERV ratings mean greater filtration but can also increase static pressure, potentially requiring system adjustments or a more robust fan. Pay attention to questions about filter compatibility and energy efficiency.
Ventilation & Air Distribution
Filtration: MERV Ratings and IAQ
Installing a filter with too high a MERV rating without checking system compatibility, leading to reduced airflow and potential equipment damage.
Ventilation & Air Distribution
Filtration: MERV Ratings and IAQ
Neglecting regular filter replacement, which causes increased energy consumption and poor indoor air quality.
Ventilation & Air Distribution
Filtration: MERV Ratings and IAQ
Assuming all filters are the same; not understanding the specific benefits and limitations of different filter types.
Ventilation & Air Distribution
Spot Exhaust
Ventilation targeting specific contaminant sources.
Ventilation & Air Distribution
General Exhaust
Ventilation for an entire room or building.
Ventilation & Air Distribution
Natural Ventilation
Air movement via wind or stack effect.
Ventilation & Air Distribution
Mechanical Ventilation
Air movement using fans.
Ventilation & Air Distribution
Make-up Air
Outdoor air supplied to balance exhaust.
Ventilation & Air Distribution
Demand-Controlled Ventilation (DCV)
Ventilation adjusted by occupancy/contaminant levels.
Ventilation & Air Distribution
Stack Effect
Air movement due to temperature differences.
Ventilation & Air Distribution
HRV/ERV
Recovers heat/energy from exhaust air.
Ventilation & Air Distribution
Exhaust Systems and Ventilation Strategies
Think 'V.E.N.T.' for Ventilation: Volume, Energy, Natural/Mechanical, Title 24.
Ventilation & Air Distribution
Exhaust Systems and Ventilation Strategies
California's Title 24, Part 6 (Energy Code) mandates specific ventilation requirements and encourages energy-efficient strategies like demand-controlled ventilation (DCV) for non-residential buildings. Be prepared for questions on minimum ventilation rates for various spaces (e.g., cubic feet per minute per person or per square foot) and the role of CO2 sensors in DCV systems.
Ventilation & Air Distribution
Exhaust Systems and Ventilation Strategies
Failing to provide adequate make-up air for exhaust systems, leading to negative pressure and reduced effectiveness.
Ventilation & Air Distribution
Exhaust Systems and Ventilation Strategies
Ignoring code-mandated minimum ventilation rates, resulting in poor indoor air quality or non-compliance.
Ventilation & Air Distribution
Exhaust Systems and Ventilation Strategies
Improperly locating exhaust outlets, which can lead to re-entrainment of contaminated air into the building.
Ventilation & Air Distribution
Exhaust Systems and Ventilation Strategies
Not considering energy recovery (HRV/ERV) for mechanical ventilation, leading to higher energy consumption.
Ventilation & Air Distribution
Thermostat
Device sensing temperature to control HVAC equipment.
Controls, Electrical & Safety
Low-Voltage Control
24V AC circuit controlling HVAC components.
Controls, Electrical & Safety
Transformer
Converts high-voltage to 24V AC for controls.
Controls, Electrical & Safety
R Terminal
Provides 24V AC 'hot' power to the thermostat.
Controls, Electrical & Safety
C Terminal
Provides 24V AC 'common' return path.
Controls, Electrical & Safety
Bimetallic Strip
Temperature-sensitive element in mechanical thermostats.
Controls, Electrical & Safety
Programmable Thermostat
Allows setting temperature schedules for efficiency.
Controls, Electrical & Safety
Smart Thermostat
Advanced thermostat with remote access and learning.
Controls, Electrical & Safety
Thermostats and Low-Voltage Controls
Remember 'RCGYW' for 'Red, Common, Green, Yellow, White' – the common colors and terminals for thermostat wiring!
Controls, Electrical & Safety
Thermostats and Low-Voltage Controls
The C-20 exam will test your knowledge of basic thermostat wiring diagrams and the function of common terminals (R, C, G, Y, W) for both conventional and heat pump systems. Pay close attention to how a thermostat 'calls' for a specific function by completing a 24V circuit.
Controls, Electrical & Safety
Thermostats and Low-Voltage Controls
Assuming a blank thermostat display means no power to the thermostat itself; it could just be dead batteries.
Controls, Electrical & Safety
Thermostats and Low-Voltage Controls
Not checking the low-voltage fuse on the control board when troubleshooting a 'no power' issue.
Controls, Electrical & Safety
Thermostats and Low-Voltage Controls
Connecting high-voltage (120V/240V) directly to thermostat terminals, which will damage the thermostat and potentially the equipment.
Controls, Electrical & Safety
Capacitor
Component storing electrical energy in an electric field.
Controls, Electrical & Safety
Start Capacitor
Provides temporary torque boost for motor startup.
Controls, Electrical & Safety
Run Capacitor
Continuously improves motor efficiency and power factor.
Controls, Electrical & Safety
Microfarad (µF)
Unit of capacitance, indicating energy storage capacity.
Controls, Electrical & Safety
PSC Motor
Permanent Split Capacitor motor, common in HVAC.
Controls, Electrical & Safety
ECM Motor
Electronically Commutated Motor, highly efficient variable speed.
Controls, Electrical & Safety
Discharge
Safely release stored electrical charge from a capacitor.
Controls, Electrical & Safety
Dual-Run Capacitor
Single unit containing two run capacitors for compressor and fan.
Controls, Electrical & Safety
Capacitors and HVAC Motors
To remember capacitor types: 'Start' with a big 'S' (for Surge of power) and 'Run' with an 'R' (for Regular, steady operation).
Controls, Electrical & Safety
Capacitors and HVAC Motors
The CSLB C-20 exam will test your knowledge of capacitor safety, identification of capacitor types (start vs. run), and their role in motor operation. Pay close attention to voltage and microfarad ratings and the importance of discharging capacitors before handling. Expect questions on troubleshooting common motor issues related to capacitors.
Controls, Electrical & Safety
Capacitors and HVAC Motors
Forgetting to discharge a capacitor before touching it, risking severe electrical shock.
Controls, Electrical & Safety
Capacitors and HVAC Motors
Replacing a capacitor with the wrong microfarad (µF) or voltage rating, leading to motor damage.
Controls, Electrical & Safety
Capacitors and HVAC Motors
Assuming a capacitor is good just because it doesn't look visibly damaged; always test with a multimeter.
Controls, Electrical & Safety
Carbon Monoxide (CO)
Odorless, colorless, toxic gas from incomplete combustion.
Controls, Electrical & Safety
Incomplete Combustion
Burning fuel with insufficient oxygen, producing CO.
Controls, Electrical & Safety
Flue
Pipe or duct for exhausting combustion gases.
Controls, Electrical & Safety
CO Detector
Device sensing and alarming dangerous carbon monoxide levels.
Controls, Electrical & Safety
Carbon Monoxide Safety and Detection
CO: C-O-LD. C-Olorless, O-dorless, L-ethal, D-etect with an alarm!
Controls, Electrical & Safety
Carbon Monoxide Safety and Detection
The California Building Code (CBC) and California Residential Code (CRC) mandate carbon monoxide detectors in dwelling units with fuel-burning appliances, fireplaces, or attached garages. Memorize the general placement rule: outside each separate sleeping area and on every level of the dwelling.
Controls, Electrical & Safety
Carbon Monoxide Safety and Detection
Ignoring flu-like symptoms, assuming it's just a cold, when it could be CO poisoning.
Controls, Electrical & Safety
Carbon Monoxide Safety and Detection
Placing CO detectors too close to fuel-burning appliances, leading to nuisance alarms.
Controls, Electrical & Safety
Carbon Monoxide Safety and Detection
Failing to replace CO detectors according to manufacturer's recommendations (typically 5-7 years).
Controls, Electrical & Safety
Carbon Monoxide Safety and Detection
Re-entering a building after a CO alarm without professional clearance.
Controls, Electrical & Safety
Cal/OSHA
California's occupational safety and health agency.
Controls, Electrical & Safety
IIPP
Injury and Illness Prevention Program, required by Cal/OSHA.
Controls, Electrical & Safety
Lockout/Tagout
Procedure to de-energize and secure equipment.
Controls, Electrical & Safety
PPE
Personal Protective Equipment, protects against hazards.
Controls, Electrical & Safety
Hazard Communication
Informing employees about chemical risks.
Controls, Electrical & Safety
Fall Protection
Measures to prevent falls from heights.
Controls, Electrical & Safety
Confined Space
Limited entry/exit, not for continuous occupancy.
Controls, Electrical & Safety
Hot Work Permit
Authorization for operations producing heat/sparks.
Controls, Electrical & Safety
Cal/OSHA Regulations and Jobsite Safety
To remember key Cal/OSHA responsibilities, think 'SAFETY': S-afety plan (IIPP), A-ssess hazards, F-all protection, E-lectrical safety, T-raining, Y-our PPE.
Controls, Electrical & Safety
Cal/OSHA Regulations and Jobsite Safety
The C-20 exam frequently tests knowledge of Cal/OSHA's Injury and Illness Prevention Program (IIPP) requirements, including its core elements. Be prepared to identify employer responsibilities regarding safety training and providing PPE.
Controls, Electrical & Safety
Cal/OSHA Regulations and Jobsite Safety
Assuming a jobsite is safe without conducting a hazard assessment.
Controls, Electrical & Safety
Cal/OSHA Regulations and Jobsite Safety
Not using required PPE because it's uncomfortable or 'just for a minute'.
Controls, Electrical & Safety
Cal/OSHA Regulations and Jobsite Safety
Failing to report near misses, which are crucial for preventing future incidents.
Controls, Electrical & Safety