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71 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Where are you most likely to find a system with air in it in a solar energy system?
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Open-loop drain-down system
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a. closed loop system
b. open-loop system c. open-loop drain down system d. none of the above |
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Which is true about black v. chrome collectors.
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Chrome emits less energy
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If a family could save 60% in energy bills, what would you recommend?
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Reduce thermostat at night
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If a pump is to be romoved or replaced, where would you locate isolation valve?
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Before and after pump.
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Which would fail in a freeze protection system in a blackout?
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Recirculation
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In freeze-protection system, which would most likely freeze?
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Tilted: ine 1/2" riser and one 1/4" riser.
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In a recirculation system, what would cause the collector to freeze?
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chrome black
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What does C-100 refer to in a freeze-protection system?
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A storage temperature high limit control device.
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One of the following has the highest efficiency.
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y-intercept = 75%; slope = .8
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What is the disadvantage of a predetermined setting for a space-heating system with a sensor at the top of the tank and a differential pre-determined setting?
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a. it is necessary to predetermine a set temperature in space-heating systems
b. there may be times when the tank pump would work, but the solar system can't heat the house. c. there may be times when the solar pump might not work, but the solar system can heat the house. D. ALL OF THE ABOVE!!! |
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The major part of a solar storage collector is:
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The collector
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The main characteristics of an evaporated tube collector is:
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A vacuum is used as insulation.
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What is the most likely cause of a system staying on all the time with 1K & 3K ohm troubleshooting is at the controls?
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electrical connections were not sealed against moisture
(first place to start troubleshooting is at the sensor terminals). |
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Pure oxygen can be used to
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Never
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Ductwork image most efficient
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Image of air blowing up to the left through curved duct.
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What aspect will the heat loss for a swimming pool be the least?
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Volume of the pool
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Advantage of plastic fiber filled roof cement?
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a. neither expands nor contracts when dry
b. it contracts c. it expands D. NONE OF THE ABOVE |
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Which are acceptable water-tight roof penetrations?
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a. flat copper flashing penetrated by the copper fluid line
b. standard plumbing roof vent stack flashing c. supply and return lines up through a pitch pocket. D. A&B (pitch pockets are now discouraged) |
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What is the maximum live load allowed on a 200 SF flat roof?
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20 psf
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You would not use rubber flashing on...
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tar & rock
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What is resistance with a circuit with 22 amps and 110 volts?
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5 ohms
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The minimum distance between supports for flexible metal conduit?
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4.5 ft for all flexible cables too, knob & tube, non-metallic, armored.
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Subcontractors sharing conduit
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Should inform prime how much surface space they will use.
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A synchronous electrical inverter...
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Converts DC to AC in the same wavelength and voltage as the power company.
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An electrical splice is made
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Inside the box
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Circuit breaker should be placed on the
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Hot (black)
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How much will it cost to burn 2 100 watt lights for a year?
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$98
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How many amps can 12 AWG carry?
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20
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The smallest guage is
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10, the highest number.
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Hardest copper pipe
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K has the greatest wall thickness
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Blue stripe on copper
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L is most common for solar
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Type L copper
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Blue
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Leads to the most corrosion
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dissimilar metals
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Least effected by corrosion
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plastic
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pipe can't be used for water supply
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PVC
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Old solar system, open faucet and water surges/spits then runs slowly
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air in the line
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When brazing horizontal joint
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top then side then bottom
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allows 1 way flow
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check valve
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BTU
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amount of water required to raise 1 pound 1 degree F
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therm is how many BTUs?
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100,000 btu/therm
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Order of work
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design-permit-install-inspect
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Gal. per CU FT
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7.5 Gal/CU FT
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Area of a circle
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pi R squared
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To hoist collector onto roof use this type of rope
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nylon
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What will Cal OSHA not accept on a 5:13 slope?
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Warning lines and headers.
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cos=
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adjacent/hypotenuse
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sin=
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opposite/hypotenuse
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tan=
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opposite/adjacent
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when drilling a hole through a rafter for electrical wire, what is the closest you can come to an edge?
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2"
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Increase the diameter of a duct 2 fold, you increase the flow
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4 fold
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typical dimensions of collector
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8x5'
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relieves internal pressure of a vessel
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T&P valve
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Current for thermal control sensors
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milliamps
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Elec garage door requires
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circuit protection
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working clearance in front of elec panel under 600v
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36"
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used to prevent current from reversing in dc to ac applications
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diode
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storage container for 50 v battery
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ventilated box
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certify solar hot water systems
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SRCC Solar Rating and Certification Corporation
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Building officials use to approve solar hot water systems
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SRCC (not UL)
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Should not make contact with Aluminum
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Steel
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Type of warranty required to qualify for rebate
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5 year full system (Emerging Renewables Program & CEC buydown).
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drilling hole through joist or beam, be this far from edge
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2"
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Fire extinguisher for asphalt fire
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dry chemical (powder)
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Most dangerous about LP tank
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burns on contact with skin
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Dangerous about LP
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Heavier than air
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Voltage above which gloves are required
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250v
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when installing collector on gravel roof, after moving gravel
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locate center of hole
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if a tank loses heat at night
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it is likely poorly insulated
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if insulation is not UV resistant
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use UV resistant vinyl paint or tape
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How do you install on tile roof
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remove tiles
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foot protection required
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when danger of something falling on you feet.
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