ThermoHelp Study Questions-4
According to RESNET standards, what is the maximum percentage of the surface area that can be compressed for grade 1 insulation? A. 0 percent B. 2 percent C. 5 percent D. 10 percent
2 percent
What is the HERS Index of a rated home that uses twice as much energy as its corresponding reference home? a. 50 b. 100 c. 150 d. 200
200
What is the surface area of a curbed wall if the curve is a half-circle with a radius of 8 feet and the wall height is 9.5 feet? a. 250 square feet b. 879 square feet c. 477 square feet d. 239 square feet
239 square feet
Which of the following scales would produce the smallest drawing? a. 3/32" = 1" b. 3/8"=1" c. 3/4" = 1" d. 3" + 1'
3/32 = 1"
What is the R-value of an assembly that has 99 percent of its surface with an R-value ofo42, and 1 percent of its surface with a R-value of 1.5? a. 21.8 b. 40.5 c. 41.6 d. 33.1
33.1
In construction terminology, what is the most common way to express the pitch of a roof that rises 6 feet in a run of 18 feet? a. 4/12 b. 6/18 c. 6/12 d. 1/3
4/12
In an effort to promote good indoor air quality, relative humidity should be maintained at which of the following levels? a. 80-100% b. 50-80% c. 40-60% d. 0-30%
40-60%
If you are using a scale of 3/16 inch per foot, how long of a line should you draw to represent a dimension of 20 feet? a. 1-7/8 inches b. 5-1/8 inches c. 5-5/8 inches d. 7-3/8 inches
5-5/8 inches
A cathedral ceiling combers a 24 foot by 24 foot addition (as measured on the exterior). The peak in the middle of the room is 13 feet high, and the lower edge of the ceiling on each side is 8 feet high (measured on the interior). What is the area of the ceiling? a 425 square feet b. 565 square feet c. 624 square feet d. 775 square feet
624 square feet
Compact fluorescent light bulbs use approximately how much energy compared to an incandescent light bulb of the same lumen rating? a. 25 percent less b. 40 percent less c. 75 percent less d. 90 percent less
75 percent less
What does the EPA recommend as the maximum allowable concentration of carbon monoxide for 8 hours of expsure? a. 3 ppm b. 9 ppm c. 45 ppm d. 100 ppm
9 ppm
Which of the following conditions would be the most likely cause of ice dams? a. A roof leak b. A chimney chase open to the attic c. Excessive attic ventilation d. Delaminated roof sheathing
A chimney chase open to the attic
Which of the following is true about sizing a furnace in a cooling-dominated climate? a. A furnace may be over sized to provide sufficient airflow for air conditioning b. A furnace must never be larger than the design heating load c. A furnace requires a dual-stage gas valve d. A furnace requires a high-velocity ducting system
A furnace may be over sized to provide sufficient airflow for air conditioning
Which quatity of fuel contains the most Btu? a A gallon of heating oil b. A gallon of propane c. A gallon of kerosene d. A therm of natural gas
A gallon of heating oil
What causes vapor diffusion? A. Vapor Pressure difference B. Capillary action C. The stack affect D. Air pressure difference
Vapor pressure difference
Which of the following may make a tight home healthier? a. Convection b. Stack effect c. Ventilation d. Back drafting
Ventilation
Which of the following will happen when you add insulation to an attic? A. Increase the U-factor of the ceiling that is being insulated b. Decrease the R-value of the ceiling that is being insulated c. Decrease the U-factor of the ceiling that is being insulated d. Increase both the U-factor and R-value of the ceiling that is being insulated
Decrease the U-factor of the that is being insulated
A HERS Index includes an analysis of the energy use associated with which of the following appliances? a. Clothes washer b. Dryer c. Dishwasher d. Microwave
Dishwasher
Which of the following results from excessive cold -weather air leakage across the building envelope? a. Dry indoor air b. Furnace short-cycling c. High indoor humidity d. Indoor air density increases
Dry indoor air
What is the customer's net price per therm of heat delivered to the house under the following conditions: gas price of $1.60/Therm, furnace AFUE of 85, and duct system efficiency of 75 percent? a. $2.13 b. $1.36 c. $2.51 d. $1.20
$2.51
If a building uses 58.567,000 Btus annually to heat with electric resistance, how much would it cost annually if a KWh cost 13 cents? a. $2231 b. $3050 c. $3412 d. $4123
$2231
A 100 square foot wall (gross) with an R-value of 13 has 20 square foot of window with a U-factor of 0.3. What is the overall "U-factor" for this wall? A. 0.077 B. 0.103 C. 0.107 D. 0.122
0.122
What is the rate of heat transfer through a 400 square foot wall whose total R-value is 20 when the outside to inside temperature diffence is 50 degrees? A. 1,000 Btu B. 1,000 Btu/hr C. 1,500 Btu/hr D. 400,000 Btu/hr
1,000 Btu/hr
For a house with a volume of 23,241 ft cubed, determine the natural air change rate (ACHnatural) if the N factor is 10.9 and CFM50=6850. a. .339 b. 1.62 c. 3.39 d. 17.7
1.62
According to the RESNET Standards for quality assurance, what minimum percentage of a rater's building files must be annually reviewed by the rating provider's quality assurance designee? a. 1 percent b. 5 percent c. 10 percent d. 20 percent
10 percent
How many Btus are in a CCF of natural gas? a. 1,000 b. 3,413 c. 100,000 d. 1,000,000
100,000
If the volume of a house is 25,000 cubic feet and the blower door test result is 5,000 CFM50, then what is the ACH50? a. 500 b. 5 c. 12 d. 10
12
Which will cost the least per million Btu delivered? a. A 80 AFUE natural gas furnace burning gas that costs$12 per MCF b. A 95 AFUE natural gas furnace burning gas that costs $12 per MCF c. An air-source heat pump with aHSPF 9.4 using electricity costing $0.10/kWh d. A grougnd loop heat pump with a COP of 3.5 using electricity costing #0.10/kWh
A grougnd loop heat pump with a COP of 3.5 using electricity costing #0.10/kWh
How is Energy Efficiency Ratio (EER) defined? a. A measure of energy efficiency for cooling equipment, in units of Btu per hour of cooling capacity divided by watts of electrical input. b. The measure of energy efficiency for cooling equipment, in units of watts of cooling capacity divided by watt hours of electrical input. c. The measure of energy efficiency for heating equipment, in units of watts of heating capacity divided by watts of electrical input. d. The measure of heating energy efficiency for heat pumps, in units of Btu per hour of capacity per watt hour of electrical input.
A measure of energy efficiency for cooling equipment, in units of Btu per hour of cooling capacity divided by watts of electrical input.
Which of the following features of a rate home affects the HERS index? A. A clothes washer B. A heated pool C. A photovoltaic array D. A microwave oven
A photovoltaic array
Who is responsible for assessing the quality assurance system of an accredited HERS provider? a. A quality assurance designee b. RESNET c. EPA ENERGY STAR home program d. A local state, utility or government agency
A quality assurance designee
What is a "ton" of cooling capacity? a. A unit of air conditioner cooling capacity that equals 24,00 Btu/hour b. The wight of an ir conditioner's outdoor condensing unit c. A unit of air conditioer cooling capacity that equals 12,000 Btu/hour d. The weight of water an air conditioner condenses in 24 hours
A unit of air conditioner cooling capcity that equals 12,000 Btu/hour
What is the formula for ACH50? a. ACH50=CFMx60/Volume b. ACH50=CFM50/60xN c. ACH50=CFM50xVolume/60 d. ACH50=CFM50x60/N
ACH50=CFMx60/Volume
To measure total duct leakage in a house with two separate duct systems, what must you do after performing a duct leakage test on each system to find the total duct leakage for the home? a. Average the CFM25 results b. Add the fan pressures of the two readings and convert to CFM25 c. Add the CFM25 results d. Use the CfM25 of the system(s) that are located in unconditioned space
Add the CFM25 results
Which two conditions must be met in order to skip a duct leakage test and enter leakage as 0 CFM25? a. All of the duct work and air handling equipment must be 100 percent visible and thoroughly sealed b. All of the duct work and air handling equipment must be thoroughly sealed and located inside the boudary of the conditioned space c. All of the duct work and air handling equipment must be 100 percent visible and located inside the boundary of the conditioned space d. All of the duct work and air handling equipment must be thoroughly sealed and inspected prior to installation of duct insulation
All of the duct work and air handling equipment must be 100 percent visible and located inside the boudary of the conditioned space
When air sealing in a cold climate, where is the most effective area to seal? a. Windows and doors b. Foundation walls c. Attic plane d. Crawlspace walls
Attic plane
What are the typical units of measurement for a heating load calculation? A. Kwh-spauare foot B. Btu/minute C. Btu/hour D. Watts/hour
C. Btu/hour
Which unit of measure for expressing house leakage is the only one measured directly by the blower door? A. ACH50 B. ELA C. CFM50 D. CFMnat
CFM50
In what duct system location would an opening of a given size leak the most during system operation? a. The supply side b. The return side c. Far from the air handler d. Close to the air handler
Close to the air handler
Which of the following will result from replacing incandescent bulbs with fluorescent bulbs? a. cooling load increases b. Heating load decreases c. Cooling load decreases and the heating load increases d. Cooling load increases and the heating load decreases
Cooling load decreases and the heating load increases
What organization rates new wood stoves for energy efficiency? a. Environmental Protection Agency b. American Society of heating, Refrigerating and Air-Conditioning Engineers c. Department of Energy d. Gas Appliance Manufacturers Association
Environmental Protection Agency
Besides convection and radiation, how else can a person lose heat from their body? A. Evaporation B. Diffusion C. Condensation D. Emissivity
Evaporation
Sweating cools your body primarily by which of the following? a. Conduction b. Radiation c. Infiltration d. Evaporation
Evaporation
Which of the following is rated by AFUE? a. Heat pumps b. Window units c. Solar systems d. Gas furnace
Gas furnace
The term for an air-source heat pump"s heating efficiency in the heating mode is: a. Seasonal Energy Efficiency Ratio b. Annual Fuel Utilization Efficiency c. Heating Energy Factor d. Heating Seasonal Performance Factor
Heating Seasonal Performance Factor
Which way does heat always flow? a. Higher to lower temperature b. Low level to higher level c. Light to dark d. Cold to hot
Higher to lower temperature
How should batt insulation be installed in a frame floor above unconditioned space? a. In contact with the bottom of the floor b. With a 1" gap between the insulation and surface it is warming c. Resting on the drywall or other material at the bottom of the joists d. With a 12" gap at the perimeter to allow for rim joist inspection
In contact with the bottom of the floor
Which home energy feature is typically found in building specifications? a. Building dimensions b. Orientation c. Thermostat set point d. InsulationR-value
Insulation R-value
Which of the following describes the portion of ahome's cooling load caused by water vapor that must be removed from an air conditioner? a. Sensible load b. Specific load c. Latent load d. Transient load
Latent load
Which strategy is an effective way to reduce mold growth in a cold climate? a. Install a forced air heating system b. Install a hydronic heating system c. Maintain indoor relative humidity below 50 percent d. Install vapor retarders on both sides of the walls
Maintain indoor relative humidity below 50 percent
What is the term for the average temperature of the surfaces surrounding a person? a. Air temperature b. Mean radiant temperature c. Relative humidity d. Average surrounding temperature
Mean radiant temperature
Which of the following materials generall has the highest conductivity? A. Metal B. Wood C. Vinyl D. Foam
Metal
During a blower door test, you can only get the house pressure to 35 Pa. the flow rate at this house pressue is 4250 CGM. what shoud you do to determine the CFM at 50 Pa? A. Install a low-flow ring and test again B. Multiply 4250 by the CRF factor for 50 Pa C. Multiply 4250 by the CRF factor for 35 Pa D. Successibely close off parts of the house until you can reach 50 Pa
Multiply 4250 by the CRF factor for 35 Pa
As outside temperature rises, how is combustion appliance draft pressure affected generally? a. Increases b. Decreases c. No change d. Can't tell with this data
No change
What does an elevation drawing show? A. One side of a house as viewed from straight on B. Two or more walls as viewed from an angle C. A detailed view of the wall, ceiling and floor construction D. The roof as viewed from above
One side of a house as viewed from straight on
What is the general formula for efficiency? a. Output/input b. Input/output c. Output x input d. (1-input)/output
Output/input
What trend(s) in new home construction has resulted in reduced air leakage compared with older (pre-1960) homes? A. Platform framing and the use of "sheet" sheathing materials B. Superior workmanship C. Building materials that are less air permeable D. Installation of fiberglass batt insulation
Platform framing and the use of "sheet" sheathing materials
When the HVAC system is operating, what is the main potential health consequence of dominate supply duct leakage located in the attic? a Pollutant may be drawn into the house b. The house may be over-pressurized by the duct leakage c. Mold may form inside the supply ducts d. Air infiltration may be less effective
Pollutant may be drawn into the house
Which of the following is likely to occur as a result of a return duct disconnected in the attic? a. Back drafting of combustion appliances within the house when the air handler runs b. A deceased whole-house infiltration rate when the air handler runs c. Poor heating or cooling distribution to one or more rooms d. Pressurization of the house with respect to the outdoors
Pressurization of the house with respect to the outdoors
High relative humidity causes people to perceive a higher temperature by which of the following? a. Reducing the rate at which perspiration can evaporate from the skin b. Making it impossible for the body to achieve thermal equilibrium c. Increasing the rate at which latent heat is transferred from the air to the skin d. Increasing the air density, making it feel heavier and hotter than it actually is
Reducing the rate at wich perspiration cann evaporated from the skin
Which two aspects of the installation of a central heat pump or air conditioning system are critical to ensure rated equipment efficiency? A. Refrigerant charge and airflow B. Air handler location and duct insulation C. Airflow and thermostat setting D. Air handler location and refrigerant charge
Refrigerant charge and airflow
Which two aspects of the installation of a central heat pump or air conditioning system are critical to ensure rated equipment efficiency? A. Refrigerant charge and airflow b. Air handler location and duct insulation C. Airflow and thermostat setting D. Air handler location and refrigerant charge
Refrigerant charge and airflow
When setting up a duct tester at a filter-backed return grill, the filter should be? A. Cleaned or replaced prior to testeing B. Removed from the return grill C. Replaced with cardboard to prevent air from passing through D. Left as is
Removed from the return grill
In addition to U-factor, SHGC, surface area and orientation, what other aspect affecting window performance must be determined? a. Shading b. Window type (casement, slider, etc.) c. Sash type d. Manufacturer
Shading
When conducting a HERS rating, what about the rated home and the corresponding "reference: home will always be the same? a. Window orientation b. Amount of air leakage c. Air conditioner efficiency d. Site location
Site location
Which of the following has direct impact of the energy consumption of the HERS reference home? a. Site location of the rated home b. Air infiltration rate of the rated home c. Compass orientation of the rated home d. Combustion zone depressurization in the rated home
Site location of the rated home
Which of the following has direct impact on the energy consumption of the HERS reference home? a. Site location of the rated home b. Air infiltration rate of the rated home c. Compass orientation of the rated home d. Combustion zone depressurization in the rated home
Site location of the rated home
What does the term "Photovotaic" refer to? a. Solar Thermal Systems b. Solar water heating c. Solar day lighting d. Solar electricity
Solar electricy
Which window orientation benefits from fixed overhangs? a. North b. East c. South d. West
South
What might excessive de-pressurization in a house cause? a. Spillage or backdrafting of combustion appliances b. Moisure damage in wall cavities c. Condensation on window d. None of the above
Spillage or backdrafting of combustion appliances
Which of the following always happens when the R-value of an assembly doubles? a. The U-factor decreases by 1/2 b. The mean radiant temperature decreases c. The U-factor doubles d. The mean radiant temperature increases
The U-factor decreases by 1/2
In an existing home there is no access to the attic side of the knee wall. With the house depressurized to 50 pascals, you measure the pressure across the knee wall. The manometer reads +15 pascals with respect to the house. What does this tell you? a. There are no big leaks between the house and the attic side of the kneewall b. The attic side of the kneewall is well-vented to the outdoors c. The boundary between the attic side of the kneewall and outdoors is tighter than the boundary between the attic side of the kneewall and house d. The boundary between the attic side of the kneewall and outdoors
The boundary between the attic side of the knee wall and outdoors is tighter that the boundary between the attic side of knee wall and the house
Which of the following affects the locations of the neutral pressure plane? a. The distribution of the leaks in a building b. The magnitude of the stack effect c. The magnitude of the leaks in the building d. Whether the building is being heated or cooled
The distribution of the leaks in a building
A house with an attched garage is depressurized to 50 pascals with reference to outdoors. At the same time, the pressure difference between the house and garage is found to be 1 pascal. Whisch of the following observations would support this condition? a. The door between the house and the garage is not fully closed b. The door between the garage and the outside is not fully closed c. There is a well installed, effective air barrier between the house and the garage d. There is a hidden leakage pathway between the garage and a well-bented attic
The door between the house and the garage is not fully closed
To measure airflow, what is required to change from depressurization to pressurization of a house during a blower door test? a. The fan direction switch must be changed to reverse the direction of fan flow b. The hoses must be changed from the input to the reference tap on the digital manometer c. The fan must be turned around in the opening and the fan pressure reference positioned outside the house c. No change is required, the blower door setup may be left in the sam configuration
The fan direction switch must be changed to reverse the direction of fan flow
When conducting a rating, the ceiling height should be measured between which two surfaces? a. The finished floor of one level to the finished floor of the level above b. The finished floor of one level to the ceiling of that same level c. The finished floor of one level to the underside of the sheathing of the level above d. The bottom of the floor joists of one level to the finished floor above
The finished floor of one level to the ceiling of that same level
Which of the following equals the net wall area of a home? A. The gross wall area of the home plus the area of the window B. The gross wall area of the home minus the area of windows C. The gross wall area of the home minus the area of windows and doors D. The gross wall area of the home minus the area of windows, doors, chimneys, and deck overhangs
The gross wall area of the home minus the area of windows and doors
Which is true when over-sizing an air conditioning system? a. The blower will run more of the time b. The house temperature will be more uniform c. The indoor humidity will be higher d. The unit will last longer because it shuts off more
The indoor humidity will be higher
What is the U-factor of an assembly? A. The resistance to heat tranger per square foot at a given temperature difference B. the rate of heat transger per square foot per degree of temperature C. The temperature difference needed to transmit heat through a given object D. R-value of the uninsulated portions of a wall assembly
The rate of heat transfer per square foot per degree of temperature
What does the term "conditioned space boundary" mean as it relates to a house? a. What you see when you look at a house from the outside b. A temperature range in which mos occupants will be comfortable c. The surfaces that separate the conditioned area of a house from unconditioned spaces to the outdoors d. The interior surfaces of a house
The surfaces that separate the conditioned area of a house from unconditioned spaces and the outdoors
Energy improvement mortgages are usually based on a comparison of which of the following? a. The total monthly cost of the mortgage plus the energy cost before and after improvements b. The appraised value of the home before and after the improvements c. The cost of energy improvements compared to the loan amount d. The present value of energy improvements compared to the projected savings
The total monthly cost of the mortgage plus the energy cost before and after the improvements
What does the term "thermal break" mean in reference to a window? a. The window frame is broken, so the thermal performance is compromised b. The glass in the window frame has a low emissivity coating that enhances thermal performance c. The dual-pane edge spacer is made of a less conductive material separating the interior from the exterior d. The window frame is constructed with less conductive material separating the interior from the exterior portion of the frame to reduce heat transfer
The window frame is constructed with less conductive material separating the interior from the exterior portion of the frame to reduce heat transfer
A 2200 square foot home has its central air handler unit located in an attached, unconditioned garage with a through-the wall return from the conditioned space. All suppy ducts are in the attic of the home, the tested air leakage to outdoors for the air distribution system is found to be 232 CFM at 25 Pascals. When measured with reference to the outdoors, the house pressue does not change when the air handler unit is turned on and off. wWhat is the likely reason? A. There is amajor air handler supply leak in the garage B. There are equal supply and return leaks C. The builing envelope is very tightly constructed D. the filter grill on the return is very dirty, preventing airflow back the iar handler unit
Ther are equal supply and return leaks
Which of the following phrases is commonly used to describe a building material or part of an assembly that allow heat energy to transmit more rapidly from one side to the other? a. Thermal bridge b. Thermal barrier c. Thermal break d. Thermal current
Thermal bridge
When solar radiation strikes untreated single glazing at a 90 degree angle, most of it is: a. Absorbed b. Reflected c. Transmitted d. Concentrated
Transmitted
`a house has two thermostatically controlled attic power vent fans. What should you do when performing a building air-tightness test on this house? a. Turn off the fans and leave any louvers or dampers "as is" b. Tell the homeowner to remove them c. Attic fan operation has no affect on building air-tightness testing d. Turn off the fans and temporarily seal off the fan opening
Turn off the fans and leave any louvers or dampers "as is"
Injected foam insulation installed in the 1970's may have contained which of the following chemicals? a. Bora silicate b. Hydrogen sulfide c. Urea-formaldehyde d. Dihydrogen monoxide
Urea-formaldehyde
When may a HERS rater be allowed to install the same energy improvements that they recommend to a customer? a. When the rater is well qualified to perform that work b. When the rater fully disclosed the potential for a conflict of interest to exist c. When the rater obtains permission from RESNET d. When the rater is proposing to work as part of a utility program
When the rater fully disclosed the potential for a conflict of interest to exist
What does measuring overhang dimensions allow a rater to determine? a. Window shading b. Roof type c. Roof area d. Window SHGC
Window shading
One difference between an EEM and a conventional mortgage is: a. an EEM is limited to a 20-year authorization b. there is no income qualification for an EEM c. an EEM is never sold on the secondary mortgage market d.an EEM may allow a homebuer to borrow more money
an EEM may allow a homebuyer to borrow more money
When a house pressure is -25 Pa WRT to outside, the pressure reading from a pressure pan covering an outlet is 3 Pa with referent (WRT) the room, the wall cavity is: A very leaky B. better connected to the inside that the outside C. better connected to the outside than the inside D. equally connected to both inside and outside
better connected to the inside than the outside
An energy rater: a. cannot be associated with the rated house in any manneyr, even if disclosed b. cannot be related to the buyer of the rated house, even if disclosed c. can rate any house as as full disclosure if conflict of interest is given d. can rate any house as long as there is not conflict of interest
can rate any house as as full disclosure if conflict of interest is given
Which is the slowest form of heat transfer? a. convection b. radiation c. conduction d. evaporation
conduction
When cool air is warmed up, its relative humidity will: A. decrease B. increase C. stay the same D. can't tell
decrease
A leak in a supply duct located in conditiond space will" A. have no affect on the house pressure with respect to outside b. make the house negative with respect to outside C. make the house positive with respect to outside D. cause the delivery air temperature to be uncomfortable
have no affect on the house pressure with respect to outside
When measuring an existing window, your height and width measurements should include: a. only the glass are b. the entire sash are c. the approximate rough opening of the window d. the window and trim
the approximate rough opening of the window
A return leak in a vented crawlspace is most likely to cause: A. the house pressure to be positive with respct to outside B. the house pressure to be negative with respect to ouside C. the house pressure will not change D. can't tell
the house pressure to be positive with respect to outside
When conducting a HERS rating on an existing home, which of the following details are essential to include on an elevation sketch of a home? A Windos B. Termite infestations C. Attic ventilation D. Evidence of moisutre damage
windows
