Wisconsin (WI) HVAC QUALIFIER Exam
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1. A technician is installing a new forced-air furnace in a residential garage in
Wisconsin. Where must the furnace be located relative to the floor to comply
with safety codes?
A) At any height, as long as it is accessible
B) Directly on the garage floor for stability
C) At least 18 inches above the floor
D) At least 6 inches above the floor
Answer: C
Explanation: The Wisconsin Uniform Dwelling Code (UDC) and mechanical codes
require that ignition sources, including furnaces and water heaters, be installed at
least 18 inches above the floor in garages to prevent ignition of flammable vapors
(e.g., gasoline fumes), which are heavier than air and accumulate near the floor.
2. What is the minimum allowable SEER rating for a new split-system air conditioner
installed in Wisconsin under federal law?
A) 13 SEER
B) 14 SEER (Northern region)
C) 15 SEER
D) 16 SEER
Answer: B
*Explanation: The U.S. Department of Energy regional standards divide the
country into North, South, and Southwest. Wisconsin is in the Northern region,
, where the minimum SEER for new split-system AC units (as of 2015 and later) is
14 SEER.*
3. A homeowner requests a furnace with 95% AFUE. Which venting system is
required for this high-efficiency unit?
A) Masonry chimney
B) Type B double-wall metal vent
C) PVC or CPVC plastic vent pipe
D) Single-wall galvanized vent
Answer: C
*Explanation: Furnaces with 90%+ AFUE produce flue gases that are cool (low
temperature) and acidic. Standard metal vents corrode quickly. These units
require sealed plastic venting (PVC, CPVC, or polypropylene) because the exhaust
temperature is low enough not to melt the plastic.*
4. According to the Wisconsin Commercial Building Code, what is the maximum
allowable length of a flexible duct connector used to reduce vibration?
A) 6 inches
B) 14 inches
C) 24 inches
D) 36 inches
Answer: B
Explanation: The Wisconsin code (based on IMC) limits flexible duct connectors to
14 inches in length for vibration isolation. This prevents sagging, tearing, and
excessive pressure drop.
5. A technician finds a cracked heat exchanger in a furnace. What must be done
immediately?
A) Seal the crack with high-temperature tape
B) Reduce gas pressure to lower flame temperature
C) Deactivate the furnace and tag it as unsafe
D) Clean the heat exchanger to improve airflow
Answer: C
, Explanation: A cracked heat exchanger can allow carbon monoxide (CO) to enter
the supply air. Wisconsin code and safety protocols require immediate deactivation
of the appliance, tagging it as unsafe, and notifying the owner in writing.
6. What is the required minimum clearance for a Type B gas vent passing through a
combustible wall in Wisconsin?
A) 0 inches (zero clearance)
B) 1 inch
C) 2 inches
D) 6 inches
Answer: B
*Explanation: Type B vents require a minimum 1-inch clearance to combustibles.
This is specified in NFPA 54/National Fuel Gas Code, adopted by Wisconsin, to
prevent heat transfer and potential fire.*
7. When brazing copper refrigerant lines, what protective gas must be flowed
through the lines to prevent oxidation?
A) Oxygen
B) Acetylene
C) Nitrogen
D) Compressed air
Answer: C
Explanation: Dry nitrogen is flowed through copper lines during brazing to displace
oxygen. Without it, copper oxide (scale) forms inside the pipes, which can
contaminate the system, clog metering devices, and damage compressors.
8. In Wisconsin, a furnace located in an unconditioned attic must have what feature
regarding its condensate drain?
A) No condensate drain is needed
B) A drain line with heat tape or insulation to prevent freezing
C) A drain line directed into the attic insulation
D) A dry trap with no water
Answer: B
, Explanation: In Wisconsin’s cold climate, condensate in unheated attics can freeze
and crack pipes or cause overflow. The code requires that condensate drains in
unconditioned spaces be protected from freezing, typically by heat tape, insulation,
or routing to a conditioned space.
9. A replacement air conditioner has a higher cooling capacity than the existing
evaporator coil. What is the most likely result?
A) Increased system efficiency
B) Liquid refrigerant floodback to the compressor
C) Reduced risk of freezing
D) Improved humidity control
Answer: B
Explanation: If the condenser is oversized relative to the evaporator, refrigerant
may not fully vaporize, leading to liquid refrigerant returning to the compressor.
Liquid is incompressible and can cause severe mechanical damage (valve failure,
broken rods).
10. What is the maximum allowable total pressure drop (static pressure) for a
residential duct system at nominal airflow?
A) 0.1 in. w.c.
B) 0.5 in. w.c.
C) 1.0 in. w.c.
D) 2.0 in. w.c.
Answer: B
Explanation: Industry standards (ACCA Manual D) and typical Wisconsin code
expectations for residential systems allow up to 0.5 in. w.c. total external static
pressure. Higher pressure drops indicate undersized ducts, causing high noise, high
energy use, and equipment failure.
11. A homeowner in Madison, WI, wants to install a ground-source (geothermal) heat
pump. What is the minimum efficiency requirement for the equipment?
A) No minimum efficiency required
B) 14 EER / 3.6 COP
Questions And Answers Rated A+ New
Update Assured Satisfaction
1. A technician is installing a new forced-air furnace in a residential garage in
Wisconsin. Where must the furnace be located relative to the floor to comply
with safety codes?
A) At any height, as long as it is accessible
B) Directly on the garage floor for stability
C) At least 18 inches above the floor
D) At least 6 inches above the floor
Answer: C
Explanation: The Wisconsin Uniform Dwelling Code (UDC) and mechanical codes
require that ignition sources, including furnaces and water heaters, be installed at
least 18 inches above the floor in garages to prevent ignition of flammable vapors
(e.g., gasoline fumes), which are heavier than air and accumulate near the floor.
2. What is the minimum allowable SEER rating for a new split-system air conditioner
installed in Wisconsin under federal law?
A) 13 SEER
B) 14 SEER (Northern region)
C) 15 SEER
D) 16 SEER
Answer: B
*Explanation: The U.S. Department of Energy regional standards divide the
country into North, South, and Southwest. Wisconsin is in the Northern region,
, where the minimum SEER for new split-system AC units (as of 2015 and later) is
14 SEER.*
3. A homeowner requests a furnace with 95% AFUE. Which venting system is
required for this high-efficiency unit?
A) Masonry chimney
B) Type B double-wall metal vent
C) PVC or CPVC plastic vent pipe
D) Single-wall galvanized vent
Answer: C
*Explanation: Furnaces with 90%+ AFUE produce flue gases that are cool (low
temperature) and acidic. Standard metal vents corrode quickly. These units
require sealed plastic venting (PVC, CPVC, or polypropylene) because the exhaust
temperature is low enough not to melt the plastic.*
4. According to the Wisconsin Commercial Building Code, what is the maximum
allowable length of a flexible duct connector used to reduce vibration?
A) 6 inches
B) 14 inches
C) 24 inches
D) 36 inches
Answer: B
Explanation: The Wisconsin code (based on IMC) limits flexible duct connectors to
14 inches in length for vibration isolation. This prevents sagging, tearing, and
excessive pressure drop.
5. A technician finds a cracked heat exchanger in a furnace. What must be done
immediately?
A) Seal the crack with high-temperature tape
B) Reduce gas pressure to lower flame temperature
C) Deactivate the furnace and tag it as unsafe
D) Clean the heat exchanger to improve airflow
Answer: C
, Explanation: A cracked heat exchanger can allow carbon monoxide (CO) to enter
the supply air. Wisconsin code and safety protocols require immediate deactivation
of the appliance, tagging it as unsafe, and notifying the owner in writing.
6. What is the required minimum clearance for a Type B gas vent passing through a
combustible wall in Wisconsin?
A) 0 inches (zero clearance)
B) 1 inch
C) 2 inches
D) 6 inches
Answer: B
*Explanation: Type B vents require a minimum 1-inch clearance to combustibles.
This is specified in NFPA 54/National Fuel Gas Code, adopted by Wisconsin, to
prevent heat transfer and potential fire.*
7. When brazing copper refrigerant lines, what protective gas must be flowed
through the lines to prevent oxidation?
A) Oxygen
B) Acetylene
C) Nitrogen
D) Compressed air
Answer: C
Explanation: Dry nitrogen is flowed through copper lines during brazing to displace
oxygen. Without it, copper oxide (scale) forms inside the pipes, which can
contaminate the system, clog metering devices, and damage compressors.
8. In Wisconsin, a furnace located in an unconditioned attic must have what feature
regarding its condensate drain?
A) No condensate drain is needed
B) A drain line with heat tape or insulation to prevent freezing
C) A drain line directed into the attic insulation
D) A dry trap with no water
Answer: B
, Explanation: In Wisconsin’s cold climate, condensate in unheated attics can freeze
and crack pipes or cause overflow. The code requires that condensate drains in
unconditioned spaces be protected from freezing, typically by heat tape, insulation,
or routing to a conditioned space.
9. A replacement air conditioner has a higher cooling capacity than the existing
evaporator coil. What is the most likely result?
A) Increased system efficiency
B) Liquid refrigerant floodback to the compressor
C) Reduced risk of freezing
D) Improved humidity control
Answer: B
Explanation: If the condenser is oversized relative to the evaporator, refrigerant
may not fully vaporize, leading to liquid refrigerant returning to the compressor.
Liquid is incompressible and can cause severe mechanical damage (valve failure,
broken rods).
10. What is the maximum allowable total pressure drop (static pressure) for a
residential duct system at nominal airflow?
A) 0.1 in. w.c.
B) 0.5 in. w.c.
C) 1.0 in. w.c.
D) 2.0 in. w.c.
Answer: B
Explanation: Industry standards (ACCA Manual D) and typical Wisconsin code
expectations for residential systems allow up to 0.5 in. w.c. total external static
pressure. Higher pressure drops indicate undersized ducts, causing high noise, high
energy use, and equipment failure.
11. A homeowner in Madison, WI, wants to install a ground-source (geothermal) heat
pump. What is the minimum efficiency requirement for the equipment?
A) No minimum efficiency required
B) 14 EER / 3.6 COP
