InterNACHI Heating, Ventilation, and Air Conditioning (HVAC) Practice Exam

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• What could happen if a pressure-relief valve setting is too high?
• Is the cabinet considered a structural part of an HRV?
• If a boiler in a Victorian home has a pressure-reducing valve set to 12 psi, is this setting considered too low?
• Can condensate leakage from the induced-draft fan housing cause corrosion of the primary heat exchanger?
• Is it necessary for heat pumps to have antifreeze in colder climates?
• Is it standard for high-efficiency boilers to have problems with induced-draft and forced-draft fans?
• Is lack of access to the coil a common problem with evaporators?
• What is the primary function of the oil vent pipe?
• Is an indoor compressor a component unique to heat pumps compared to central air-conditioning systems?
• What is true regarding refrigerant lines?
• Is it true that a corroded oil-storage tank is usually not worth reporting?
• Which component is essential for distributing conditioned air in HVAC systems?
• Which component is a common part of heat pumps and air conditioners?
• Should the evaporator coil be positioned upstream of the furnace’s heat exchanger?
• What function does a thermostat serve in HVAC systems?
• What is a common problem related to barometric dampers?
• Is leaking a common problem associated with condensers?
• Which safety control prevents water in a boiler system from becoming super-heated?
• What role do inlet and exhaust fans play in an HRV?
• The smaller appliance vent should connect into the chimney ________ the vent from the larger appliance.
• In HVAC systems, which factor is most important for energy efficiency?
• Is it possible for a vent damper to fail in the closed position?
• True or False: A home inspector should test all automatic safety controls.
• What action should be taken if corroded vents are found during an inspection?
• Where is the compressor typically located in an air-to-air split-system air conditioner?
• True or False: A compressor is a common component of heat pumps and air conditioners.
• What HVAC component is often used to control the overall performance of the system?
• Is a single-stage compressor a component that is common in both heat pumps and central air-conditioning systems?
• A common problem with barometric dampers is misadjusted air draft.
• True or False: Forced-air HVAC systems use fans and ducts to move air around the house.
• Is frost buildup a frequent issue with evaporator coils?
• What percentage is the threshold for high-efficiency gas furnaces in terms of AFUE?
• Are condensate handler issues commonly found in high-efficiency boilers?
• Are corroded vents a common problem with sidewall-vented mid-efficiency oil furnaces?
• Are oversized HVAC ducts commonly considered a problem?
• True or False: An auxiliary electric heating system is typically installed upstream of the heat pump coil.
• Is improper location for the vent termination a common problem with sidewall-vented mid-efficiency oil furnaces?
• What should be done if high levels of carbon monoxide are detected in a home?
• What is the normal setting for a pressure-relief valve?
• What happens when a heat exchanger fails in a boiler?
• Which component differentiates heat pumps from traditional air conditioning systems?
• What might indicate a faulty installation in a gas furnace?
• Are high-level returns more effective for heating or cooling?
• Which issue is most likely found at the condenser site of an HVAC system?
• Corrosion is a common problem found in which component of HVAC systems?
• What is the purpose of the thermostat in an HVAC system?
• Does reducing off-cycle losses improve steady-state efficiency?
• How does flexible ductwork compare to rigid ductwork in terms of friction loss?
• Furnaces rated at average efficiency tend to experience what percentage of off-cycle losses of the fuel they consume?
• A pump control is an operating control found on a hydronic system. What is the correct answer?
• Are combustion air and venting problems typical for high-efficiency boilers?
• What problem may occur if a black steel pipe connects with copper pipe?
• The vent in a high-efficiency furnace should slope in what direction?
• An indoor fan is typically found in which type of system?
• What impact does the design of return ducts have on HVAC system performance?
• Inadequate air draft is a common problem with barometric dampers.
• What is the designation of the smaller refrigerant line?
• What is the most common fuel source for residential heating systems?
• Are automatic air vents mandatory on all boilers?
• What is the typical location of the condenser fan in a split-system air-conditioning unit?
• Are zone valves considered operating controls in hydronic systems?
• Which of the following is a common problem with condensers?
• It is _______ in many jurisdictions for electrical wiring and plumbing pipes to be run inside return ducts.
• What is the minimum outdoor temperature a heat pump should not be operated in cooling mode?
• During which season does a heat pump primarily act as a heating system?
• What is the normal operating pressure for a boiler?
• Which of the following is NOT a component of HRV systems?
• What role does duct insulation play in HVAC systems?
• The vent connector should slope ______ going away from the furnace at a minimum of _____ per foot.
• Mixing convectors and radiators in a hydronic system often affects heating regulation. True or False?
• What type of efficiency does reducing off-cycle losses primarily improve?
• Which of the following components is crucial for the heat-exchange process in air conditioning?
• What is the primary function of a thermostat in an HVAC system?
• What type of heating system may operate in conjunction with a heat pump for additional backup?
• True or False: An expansion device is a common component of heat pumps and air conditioners.
• Do high-efficiency boilers frequently experience problems with heat exchangers?
• A heater thermostat located in the kitchen will tend to keep the rest of the house _______ than is desirable.
• Is a triple-split system found in some heat pumps while absent in central air-conditioning systems?
• What type of wall is recommended for radiator installation?
• Is a dry evaporator top considered a common issue for evaporators?
• When there is one large return register located in the center hallway, what is the first course of action?
• An unprotected oil-storage tank is a concern in the context of a general home inspection.
• Is an outdoor air-temperature sensor a component of heat pumps that differs from central air-conditioning systems?
• In heat pump systems, the primary role of the condenser coil is to __________.
• Do mono-port burners typically have a larger output than ribbon burners?
• A common problem with oil furnace vent connectors is that they can become loose. True or False?
• Which component is responsible for exhausting products of combustion in a gas furnace?
• The indoor coil on a heat pump acts as an evaporator coil in the summer and a __________ coil in the winter.
• What does the classification of a thermostat as an operating control imply?
• What is a significant issue affecting the efficiency of tankless coil systems?
• Is it possible for a boiler to operate without a pressure-reducing valve?
• Does flexible ductwork experience more or less friction loss compared to rigid ductwork?
• Which of the following components is common to both heat pumps and air conditioners?
• The post-purge cycle on an induced-draft fan ensures that what is exhausted?
• What does a circulator do in a hydronic system?
• Is it acceptable to install a gas meter under the drip line of a roof?
• Are heat pumps distinctively regulated by a specific code from central air-conditioning systems?
• What common problem do high-efficiency boilers face regarding their ignitions?
• What is the typical cooling load in a southern U.S. climate per ton?
• True or False: Accumulation of dirt on condensers can lead to reduced efficiency.
• What type of draft do forced oil burners rely on?
• What is a common indication of a malfunctioning air-conditioning system?
• Power venters are never allowed on conventional oil furnaces. True or False?
• In most HVAC systems, where is the evaporator coil typically located?
• What is the typical setting for a low temperature limit or primary control at a boiler?
• It's common to find inadequate clearance from oil furnace vent connectors to nearby combustibles. True or False?
• Does a heating climate require less air to cross an evaporator coil compared to a conventional furnace's heat exchanger?
• Do flow-measuring stations exist as components of an HRV?
• What is a typical problem with supply registers located in individual rooms without proper return paths?
• What is a disadvantage of oversized ducts in HVAC systems?
• Which component is critical for filtering air in HVAC systems?
• What is the primary function of the heat exchanger in HVAC systems?
• Is it common for high-efficiency boilers to have problems with the cabinet?
• True or False: An outdoor coil is a common component of heat pumps and air conditioners.
• Should hydronic systems be tested for adequate capacity during an inspection?
• Are pressure-reducing valves necessary for functionality in all boiler systems?
• What is the typical lifespan of a conventional gas furnace?
• Which of the following is a component of a Heat Recovery Ventilator (HRV)?
• What type of HVAC system is most commonly found in residential settings?
• What should home inspectors check in the air-handling system?
• Most residential heating systems are of _______ output.
• Heat pumps are generally sized based on the __________.
• Is it necessary for the inspector to report on the presence of a cool-air supply to each room?
• Does a two-stage thermostat differentiate heat pumps from central air-conditioning systems?
• What component helps in distributing hot water in a hot-water heating system?
• Must the vent connector from an oil-fired furnace connect to the chimney above the vent connector from the water heater?
• When gas is compressed, what happens to its temperature?
• Which refrigerant line is larger and commonly contains a liquid?
• Do evaporators often encounter issues due to not being cleaned regularly?
• What is an important function of duct insulation in HVAC systems?
• The first type of heating system that didn't require manual stoking was fueled by _________.
• What is a common operational issue faced by barometric dampers?
• An underground oil-storage tank falls outside what aspect of inspection?
• Are safety and operating control issues common in high-efficiency boilers?
• Do sidewall-vented mid-efficiency oil furnaces often suffer from poor reliability?
• What is the method to test the air-conditioning system?
• Which of the following does NOT describe a characteristic of radiant heating systems?
• Is a pump considered a component in a hot-water distribution system?
• What operational aspect can lead to inefficiency in high-efficiency boilers?
• The typical cooling load in a moderate climate is how many square feet per ton?
• Is a heat exchanger a component of an HRV?
• Are distribution problems common with high-efficiency boilers?
• Which type of heating system is known for being energy efficient and environmentally friendly?
• What is a common problem found with central air conditioning systems?
• What is the consequence of a malfunctioning high-temperature limit switch?
• What is the average temperature setting for a high-temperature limit switch?
• What is a common problem found with water-cooled coils?
• What is generally not a result of scorching inside a burner access door?
• Inspectors should check for poor slope at oil furnace vent connectors. True or False?
• Which situation is a direct result of not having adequate combustion air?
• True or False: A balancing valve completely shut off will result in no water flow in the radiator.
• Which issue can cause sidewall-vented mid-efficiency oil furnaces to function poorly?
• What is a potential consequence of vent blockage in a gas furnace?
• Do radiant piping systems require bleed valves?
• True or False: An indoor coil is a common component of heat pumps and air conditioners.
• When considering whether an automatic air vent is needed, what code should be followed?
• If high levels of carbon monoxide are detected at the furnace supply registers, what should the inspector do first?
• What type of system primarily relies on refrigerant lines?
• What is typically the main concern with rooftop package units regarding the heat exchanger?
• What is a typical cause of malfunction in barometric dampers during an inspection?
• What is a common characteristic of air filters in HVAC systems?
• The minimum required clearance from a single-wall exhaust flue at an oil furnace to combustibles is _____ inches.
• What maintenance issue can arise with high-efficiency boiler fans?
• True or False: A home inspection includes using normal operating controls to check the heating system.
• Is it mandatory for every oil furnace to have a barometric damper?
• Oil furnace vent connectors are often poorly supported. True or False?
• Which material is rarely used as an exhaust vent for oil combustion gases due to their temperature?
• What is easier to diagnose when compared to furnaces, according to heating system characteristics?
• Why is the placement of the vent pipe important in high-efficiency furnaces?
• What is the purpose of a backflow preventer in a hydronic system?
• Does a leaking oil tank fall outside the scope of a general home inspection?
• Is an outdoor air thermostat classified as an operating control in hydronic systems?
• Which is preferred: an undersized air conditioner or an oversized one?
• When extending a black steel pipe with copper pipe, what potential issue may arise at the junction?
• Is a radiant piping system considered a style of heat delivery used with boilers?
• Which issue is commonly associated with barometric dampers?
• Under proper tension, a belt should deflect about _____ inch(es).
• What is the primary purpose of duct systems in HVAC?
• What type of water is commonly used to cool a coil that is part of an HVAC system?
• The purpose of the HVAC portion of a general home inspection is to ensure that the system _________.
• Are issues with boiler water temperature common in tankless coil water heaters?
• What does the term 'suction line' refer to in HVAC terminology?
• What is the typical temperature drop from outdoors to indoors with a properly operating air-conditioning system?
• Should a home inspector test a pressure-relief valve for functionality?
• What is one major benefit of using a condensing furnace?
• Warm air rising off the pavement on a hot day is an example of heat transfer by __________.
• Which statement is true regarding a compressor in HVAC systems?
• Is corrosion a common issue encountered on evaporators in HVAC systems?
• What is likely causing a wavering flame at one burner in a gas furnace when the blower activates?
• Is a pressure-reducing valve an operating control found on a hydronic system?
• What is the purpose of the primary controller on a conventional oil furnace?
• What is the main concern regarding condensation in high-efficiency furnaces?
• Is rusting a common problem found on vent connectors of oil-fired furnaces?
• Is a duct system considered a component of an HRV?
• Should an inspector activate the air-conditioning system to test it if it has been shut down?
• What is the primary function of the compressor in a heat pump?
• Do heat pumps require specific refrigerants that differ from those in central air-conditioning systems?
• In a hydronic system, mixing two types of heat delivery devices can lead to what outcome?
• In a heating-only climate, an uninsulated heating duct running through a garage will deliver ______ air to the room at the other end of the duct.
• Vent connectors should be less than ____ feet long.
• Which of the following problems is considered commong for condensers?
• Is it essential to perform regular maintenance on heat pumps to avoid efficiency problems?
• True or False: A convector is a style of heat-delivery system used with boilers.
• Is a thermostat considered an operating control found on hydronic systems?
• Which component is essential for improving air quality in HVAC systems?
• Under sizing is a common problem found with oil furnace vent connectors. True or False?
• True or False: A return grille allows the user to modulate the air flow.
• Is it common to find insulation on both refrigerant lines of heat pumps and air conditioners?
• What does HRV stand for in HVAC terminology?
• What type of contaminants typically accumulate on condensers over time?
• Is the evaporator coil designed to function effectively in a heating climate?
• The oil burner in a conventional furnace requires oil to be what before it can be ignited?
• What can indicate that an exhaust vent material is inappropriate for hot gases?
• What is the maximum desirable temperature for an 8-foot ceiling in a room with radiant pipe heating?
• Which component in a heat pump system helps regulate the flow of refrigerant?
• Leakage is frequently seen in which type of HVAC coil?
• Why are boilers with tankless coil domestic water heaters considered inefficient?
• Using a mirror and flashlight to view the heat exchanger on a gas furnace allows the inspector to see _________ heat exchanger.
• The evaporator coil on a split system is typically located in which area?
• True or False: A gas furnace back-up system typically has the heat exchanger located upstream of the heat pump coil.
• A heat pump may detect a temperature difference between the outdoors and indoors that is __________ what an air conditioner would detect.
• How do copper-tube boilers typically compare to cast-iron boilers in terms of heat-transfer characteristics?
• The average seasonal efficiency of a condensing furnace is what percentage?
• What is the typical pressure of a residential oil-burner pump?
• What type of air does an evaporative cooler recirculate across itself?
• A common problem with barometric dampers is lack of air draft.
• Before ignition, oil must be what?
• Is a crack in the heat exchanger of a rooftop package unit considered a concern?
• If a radiator's balancing valve is completely shut off, will there be water in the radiator?
• What component of a forced-air system is used to distribute heated air throughout a home?
• What is the primary purpose of an HVAC air filter?