South Carolina Packaged Equipment Heat Pump Contractor Examination

Field refrigerant lines serving packaged heat-pump equipment should be installed with which copper product?

• AType M plumbing copper that has been used for potable water
• BACR (air-conditioning and refrigeration) copper tubing that is cleaned, dehydrated, and c…
• CSchedule 40 PVC pressure pipe
• DGalvanized steel sprinkler pipe

Per 2021 IMC Table 305.4 as adopted in the South Carolina Mechanical Code, what is the maximum horizontal hanger spacing for copper or copper-alloy tubing?

• A4 feet
• B8 feet
• C12 feet
• D15 feet

While brazing copper refrigerant tubing, dry nitrogen should be flowed through the tube primarily to:

• ARaise the brazing temperature so the alloy flows faster
• BPrevent internal copper oxide scale from forming on the tube wall
• CPressure-test the finished joint at the same time it is heated
• DReplace the need for a phosphorus-bearing filler metal

Refrigerant piping located in areas other than the room or space that contains the refrigerating equipment shall be identified at intervals not exceeding:

• A10 feet
• B20 feet
• C30 feet
• D50 feet

Exposed refrigerant piping installed in open spaces that afford passage shall be not less than how far above the finished floor?

• A6 feet 0 inches
• B6 feet 8 inches
• C7 feet 3 inches
• D8 feet 0 inches

Condensate piping from a cooling coil shall have a minimum slope in the direction of discharge of:

• A1/16 inch per foot
• B1/8 inch per foot
• C1/2 inch per foot
• DNo slope if a condensate pump is used at the end of a long level run

Outdoor refrigerant-circuit access ports on packaged equipment shall be:

• ALeft as open Schrader cores so gauges can be attached quickly
• BFitted with locking-type tamper-resistant caps or otherwise secured against unauthorized…
• CReplaced with solid plugs after charging so they can never be reused
• DPainted the same color as the cabinet and left uncapped

Suction (cold-gas) refrigerant lines are insulated primarily to:

• AIncrease compressor superheat by adding heat to the vapor
• BPrevent surface condensation and reduce unwanted heat gain into the refrigerant
• CSatisfy a fire-resistance rating in place of a shaft enclosure
• DProtect the line from ultraviolet light only

Per IMC Table 305.4, the maximum horizontal support spacing for steel pipe is:

• A4 feet
• B8 feet
• C12 feet
• D15 feet

Where vibration isolation is used under packaged mechanical equipment, IMC 301.13 also requires:

• AThat the isolators be the sole means of resisting wind and seismic loads
• BAn approved means of supplemental restraint
• CThat isolation be omitted on all rooftop units in South Carolina
• DSteel springs without limit stops or snubbers

A packaged rooftop heat pump is set on spring isolators on a steel dunnage frame. The isolators' primary purpose is to:

• AIncrease the unit's heating capacity at low outdoor temperatures
• BReduce structure-borne vibration and sound transmitted into the building
• CReplace the need for seismic or wind restraint
• DSupport snow drift loads in place of the roof structure

One refrigeration ton is equal to:

• A1,000 Btu/h
• B10,000 Btu/h
• C12,000 Btu/h
• D15,000 Btu/h

Sensible heat is the heat that:

• AChanges only the moisture content of air
• BChanges the dry-bulb temperature of air without a change of state of the moisture
• CIs released only when refrigerant condenses in the outdoor coil
• DExists only as solar radiation through glass

R-410A is classified by ASHRAE 34 / IMC Table 1103.1 as which safety group?

• AA1
• BA2L
• CB1
• DA3

ACCA Manual N is the procedure used to calculate:

• AResidential room-by-room loads only
• BHeating and cooling loads for small commercial buildings
• CResidential duct sizes and equivalent lengths
• DManufacturer expanded ratings for equipment selection only

Unless a code, regulation, or documented health requirement supersedes them, ACCA Manual J indoor design dry-bulb temperatures are:

• A65°F heating and 80°F cooling
• B68°F heating and 78°F cooling
• C70°F heating and 75°F cooling
• D72°F heating and 72°F cooling

As outdoor dry-bulb temperature falls, the heating capacity of an air-source packaged heat pump:

• AIncreases because the compressor works harder
• BRemains equal to the AHRI 47°F rating at all outdoor temperatures
• CDecreases because less heat is available to absorb at the outdoor coil
• DChanges only the latent capacity, not the sensible heating output

Using Q = 1.08 × cfm × ΔT, the sensible heating delivered by 1,600 cfm of air with a 20°F temperature rise is approximately:

• A16,000 Btu/h
• B32,000 Btu/h
• C34,560 Btu/h
• D48,000 Btu/h

Using Q = 0.68 × cfm × Δgrains, the latent load for 1,200 cfm and a 40-grain humidity-ratio difference is:

• A16,320 Btu/h
• B32,640 Btu/h
• C48,000 Btu/h
• D1,200 Btu/h

In a Manual J or Manual N load, outdoor air that leaks unintentionally through the building envelope is called:

• AVentilation
• BInfiltration
• CExhaust
• DTransfer air

Oversizing a packaged cooling unit well beyond the calculated sensible and latent loads most commonly causes:

• ALonger run times and better dehumidification
• BShort cycling and poor humidity control
• CA guaranteed increase in SEER
• DLower supply-air temperature that always improves comfort

Compared with a typical Manual J residential calculation, a Manual N commercial load must also include:

• AOnly wall and roof conduction, because internal gains are ignored
• BOccupant density, lighting, and process or equipment gains at the peak hour
• COnly infiltration, because commercial buildings have no ventilation
• DA flat 400 square feet per ton factor in place of room loads

For a packaged air-source heat pump in a South Carolina cooling-dominant climate, the preferred load-and-selection approach is to:

• ASize the unit only to the winter heating load and ignore latent cooling
• BSize cooling to the peak sensible and latent cooling load, then check heating capacity at…
• CDouble a square-footage rule of thumb so the unit never runs continuously
• DSelect heating capacity at the 47°F AHRI point and assume it holds at design winter tempe…

A packaged rooftop heat pump typically contains which of the following in one outdoor cabinet?

• AOnly the compressor; the indoor blower and coil are always in a remote air handler
• BCompressor, indoor (supply) blower, indoor coil, outdoor coil, and outdoor fan
• CA hydronic boiler and a chilled-water coil only
• DOnly a gas furnace heat exchanger with no refrigerant circuit

External static pressure (ESP) is:

• AThe difference between indoor and outdoor barometric pressure
• BThe fan pressure available to overcome the resistance of ducts, filters, coils, and fitti…
• CThe refrigerant high-side pressure converted to inches of water
• DOnly the pressure drop of the throwaway filter

A duct traverse with a pitot tube and manometer is used during TAB to measure:

• ARefrigerant superheat
• BVelocity pressure, which is converted to air velocity and then to cfm
• CGas manifold pressure in inches of water column
• DCompressor oil pressure

If a packaged-unit supply fan's speed increases 10 percent and the system remains the same type of resistance, airflow (cfm) will:

• ARemain the same because duct size did not change
• BIncrease approximately 10 percent, because cfm varies directly with rpm (Fan Law 1)
• CIncrease approximately 21 percent, because cfm varies with the square of rpm
• DDecrease 10 percent because static pressure rose

The preferred sequence to air-balance a packaged rooftop system is to:

• AClose every branch damper, then open them at random until the thermostat is satisfied
• BVerify nameplate data and rotation, confirm filters and coil cleanliness, set fan speed t…
• CCharge refrigerant first and skip airflow measurements if the unit is new
• DAdjust only the room thermostat anticipator

The minimum circuit ampacity (MCA) on a packaged-unit nameplate is used to:

• ASize the branch-circuit conductors feeding the unit
• BSelect a fuse larger than the maximum overcurrent protection (MOP)
• CSize the gas supply pipe
• DSize the supply duct

Packaged heat-pump thermostat control circuits are most commonly:

• A12-volt DC automotive circuits
• B24-volt Class 2 circuits supplied by a control transformer
• C480-volt three-phase line voltage to the subbase
• DThermocouple millivolt circuits only

On a ladder (line) diagram, electrical loads are typically shown:

• AIn a pictorial outline of the cabinet only, with no circuit logic
• BAcross the two vertical power rails, with their controlling contacts in series with each…
• CAs a three-dimensional isometric of the rooftop curb
• DOnly as refrigerant flow arrows

On most North American packaged heat-pump thermostats, the O terminal:

• AEnergizes the indoor fan only
• BEnergizes the reversing valve in cooling
• CIs the 24-volt common
• DIs used only for emergency heat

A refrigeration machinery room is required when:

• AAny split-system condensing unit is installed outdoors
• BThe refrigerant quantity in an independent circuit exceeds the amounts in IMC Table 1103.…
• CA packaged rooftop unit is set on a curb
• DOnly ammonia is used, never halogenated refrigerants

Unless the outdoor-penthouse exception applies, machinery rooms shall be:

• ASealed with no outdoor air so leaked refrigerant cannot escape
• BMechanically ventilated to the outdoors
• CExhausted into an exit corridor to dilute the leak
• DAllowed to use only operable windows for emergency ventilation

The defining feature of packaged air-conditioning or heat-pump equipment is that:

• AThe complete refrigerant circuit is factory-assembled in a single cabinet, typically inst…
• BIt is always water-cooled
• CIt never uses ductwork
• DIt can include hot-water or steam boilers under the South Carolina packaged-equipment lic…

Direct-expansion (DX) cooling means that:

• AChilled water is the only fluid in the indoor coil
• BRefrigerant evaporates directly in the coil that cools the airstream
• COnly an evaporative cooler wets a pad to cool the air
• DA heat wheel is the sole means of cooling

A packaged heat pump that uses a thermostatic expansion valve (TXV) is typically charged by measuring:

• ASuperheat only, as if it had a fixed orifice
• BSubcooling
• CCompressor oil pressure
• DOnly the nameplate factory charge, with no field check of temperatures

A packaged unit with a fixed-orifice (piston) metering device is typically charged by measuring:

• ASubcooling
• BSuperheat
• COnly the high-side pressure at any outdoor temperature
• DOnly compressor amperage

Typical design supply airflow across a packaged DX cooling coil is about:

• A150 cfm per ton
• B350 to 450 cfm per ton (commonly 400 cfm per ton)
• C800 cfm per ton
• D1,200 cfm per ton

SEER (Seasonal Energy Efficiency Ratio) rates:

• ASeasonal heating efficiency of a heat pump
• BSeasonal cooling efficiency in Btu of cooling per watt-hour of electricity
• CAnnual fuel utilization of a gas furnace
• DOnly the single-point EER at 95°F outdoor

The primary purpose of the reversing valve in a packaged heat pump is to:

• AMeter refrigerant into the evaporator
• BReverse refrigerant flow so the indoor and outdoor coils swap evaporator and condenser ro…
• CUnload the compressor cylinders
• DReplace the need for a defrost control

In heating mode, the outdoor coil of an air-source packaged heat pump:

• AActs as the condenser and rejects heat outdoors
• BActs as the evaporator and absorbs heat from outdoor air
• CIs valved off and unused
• DOnly subcools liquid after the indoor coil

HSPF (Heating Seasonal Performance Factor) measures:

• ASeasonal cooling efficiency of an air conditioner
• BSeasonal heating efficiency of a heat pump, in Btu of heat per watt-hour
• CAnnual fuel utilization of a gas furnace
• DOnly the COP at a single 47°F rating point

The balance point of a heat-pump system is:

• AThe outdoor temperature at which heat-pump output equals the building heat loss
• BThe temperature at which the reversing valve automatically shifts
• CThe point at which superheat equals subcooling
• DThe pressure at which the high-pressure switch opens

Auxiliary (supplemental) heat on a packaged heat pump:

• AIs identical to emergency heat and always locks the compressor out
• BStages on when the heat pump cannot meet the load, while the compressor continues to run
• COperates only in the cooling season
• DMay be used only on gas-fired packaged units