Florida Certified Rooftop Solar Heating Installation Specialty Contractor Exam

The DBPR/CILB Rooftop Solar Heating Installation Specialty Contractor trade knowledge exam is organized into how many content areas, and what is the largest weighted area?

• A10 content areas; Installation Practices for Solar Heating Systems at 18.5%
• B8 content areas; Solar Thermal System Design at 15.5%
• C10 content areas; Hydraulics and Plumbing at 20%
• D7 content areas; Electrical Basics for Solar Installers at 15%

The Rooftop Solar Heating Installation exam has 50 scored questions with a 70% passing score. How many questions must a candidate answer correctly to pass?

• A35
• B30
• C38
• D40

Which statement correctly distinguishes the Rooftop Solar Heating Installation specialty contractor license from the Certified Solar Contractor (CV) license?

• AThe rooftop solar heating license is limited to residential solar domestic hot water and…
• BThe rooftop solar heating license covers photovoltaic installations on one-to-three famil…
• CBoth licenses have identical scope; the rooftop solar heating license is simply the regis…
• DThe rooftop solar heating license allows commercial solar water heating, while the CV lic…

Solar radiation reaching a collector includes direct (beam), diffuse, and reflected components. On a clear Florida day at solar noon, which component typically contributes the most energy to a south-facing tilted collector?

• ADirect (beam) radiation
• BDiffuse radiation
• CReflected (albedo) radiation
• DAll three components contribute equally

What is the key distinction between an active and a passive solar water heating system?

• AActive systems use a pump or controller to circulate fluid; passive systems rely on natur…
• BActive systems use photovoltaic panels; passive systems use thermal collectors
• CActive systems require antifreeze; passive systems use only water
• DActive systems are grid-tied; passive systems are off-grid

A flat-plate solar thermal collector consists of several key layers. Which assembly correctly lists the absorbing component that converts solar radiation to heat?

• AAn absorber plate with a selective surface coating, bonded to flow tubes
• BA tempered glass cover with low-iron content
• CA layer of polyisocyanurate rigid insulation behind the frame
• DAn aluminum extrusion frame with weep holes

Evacuated tube collectors generally outperform flat-plate collectors under which condition?

• AAt high collector operating temperatures and low ambient temperatures, because the vacuum…
• BAt low operating temperatures close to ambient, because the tubes have more surface area
• COn hot Florida summer days with high irradiance and warm air, due to lower reflectance
• DFor swimming pool heating where water temperature is near ambient

What is the purpose of a selective surface coating on a solar thermal absorber plate?

• AHigh absorptance in the solar spectrum with low emittance in the infrared, reducing radia…
• BTo reflect visible light away from the absorber to prevent overheating
• CTo increase the collector's reflectance so it can be used with concentrating optics
• DTo provide corrosion resistance to the copper flow tubes only

Which storage tank material is most commonly used in residential solar domestic hot water systems and is favored for its corrosion resistance when paired with a sacrificial anode?

• AGlass-lined (vitreous enamel) steel tank
• BUnlined carbon steel tank
• CAluminum tank with no lining
• DGalvanized steel tank without an anode

In an indirect (closed-loop) solar water heating system, what is the primary function of the heat exchanger?

• ATo transfer heat from the collector loop fluid to the potable water without mixing the tw…
• BTo increase system pressure above the supply water pressure
• CTo filter sediment out of the potable water before it enters the tank
• DTo convert solar thermal energy directly into electricity for the pump

A closed-loop solar thermal collector array has 80 ft² of collector area. Using the FSEC-recommended flow rate of about 1 gpm per 40 ft² of collector, what is the recommended circulating pump flow rate?

• A2 gpm
• B1 gpm
• C4 gpm
• D0.5 gpm

What does a differential temperature controller do in an active solar water heating system?

• ATurns the circulator pump on when the collector is warmer than the storage tank by a set…
• BMaintains a constant water temperature at the tap by mixing cold water
• CMeasures solar irradiance and shuts the system down at night
• DRegulates the pressure of the closed-loop antifreeze circuit

Why do quality flat-plate solar collectors use low-iron, tempered glass as the glazing material?

• ALow-iron glass transmits more solar radiation than ordinary glass, and tempering provides…
• BLow-iron glass reflects infrared heat back into the absorber while blocking all visible l…
• CLow-iron glass is chosen because it is cheaper than普通 glass
• DTempered glass blocks ultraviolet radiation to protect the absorber coating from fading

What does the SRCC OG-100 standard certify for a solar thermal collector?

• ACollector thermal performance ratings, including efficiency, heat loss coefficient, and i…
• BComplete solar water heating system durability and energy savings
• COnly the structural wind load rating of the collector mounting frame
• DThe minimum warranty period the manufacturer must offer

In Florida (roughly 25-30 degrees north latitude), what collector tilt angle is generally recommended for a year-round solar domestic hot water system to maximize annual energy collection?

• AApproximately equal to the local latitude
• BLatitude plus 15 degrees to favor winter collection
• CLatitude minus 15 degrees to favor summer collection
• DFlat (0 degrees) horizontal on the rooftop

For a solar thermal collector in the northern hemisphere, which azimuth orientation maximizes annual energy collection, and within what approximate range of east or west of true south is performance loss generally acceptable?

• ATrue south, within about 30 degrees east or west
• BTrue north, within 15 degrees
• CDue east, within 10 degrees of east
• DDue west, within 5 degrees

A contractor is selecting a solar water heating system for a home in central Florida where freezing temperatures occur a few nights per year. Which system type is generally most appropriate to provide reliable freeze protection with reasonable efficiency?

• AIndirect (closed-loop) antifreeze system with a propylene glycol heat-transfer fluid and…
• BDirect open-loop system with no freeze protection, relying on a manual drain valve
• CThermosiphon system with the tank mounted outdoors above the collector on the roof
• DIntegrated collector storage (ICS) system with no freeze protection

How does a drainback solar water heating system provide freeze protection?

• AThe collector fluid drains into a reservoir each time the pump stops, leaving the collect…
• BAn antifreeze solution circulates continuously through the collectors at all times
• CA electric heating tape warms the collector piping when the temperature drops below 32 F
• DThe system automatically recirculates warm tank water through the collectors whenever fre…

In a thermosiphon solar water heating system, where must the storage tank be located relative to the collector for the system to circulate without a pump?

• AAbove the collector, so warmer, less dense water rises from the collector into the tank a…
• BBelow the collector, so gravity pushes water downward into the collector
• CAt the same elevation as the collector to keep pressures balanced
• DInside the living space regardless of the collector position

Integrated collector storage (ICS) systems are best suited for which climate and application?

• AWarm, mild climates where freezing is rare, serving a household with moderate daytime hot…
• BCold climates with frequent hard freezes, serving a large family with high demand
• CAny climate, because the stored water provides built-in freeze protection
• DOnly for swimming pool heating, not for domestic hot water

A residence has 4 occupants. Using the common FSEC sizing guideline of about 20 gallons of daily hot water use per person, what is the estimated daily hot water load?

• A80 gallons per day
• B40 gallons per day
• C100 gallons per day
• D60 gallons per day

Using the FSEC guideline of roughly 20 ft² of collector per occupant for a domestic hot water system, how much collector area should a contractor plan for a 3-person household?

• A60 ft²
• B40 ft²
• C80 ft²
• D100 ft²

Water flows through a solar collector loop at 2 gpm and enters the collector at 80 F, leaving at 100 F. Using the formula BTU/hr = gpm x 500 x temperature rise, what is the rate of heat collected?

• A20,000 BTU/hr
• B10,000 BTU/hr
• C40,000 BTU/hr
• D5,000 BTU/hr

What does the solar fraction of a solar water heating system represent?

• AThe fraction of the total annual hot water energy load supplied by the solar system, with…
• BThe ratio of collector area to storage tank volume
• CThe percentage of available sunlight that the collector absorbs
• DThe fraction of the total system cost paid through incentives

An indirect solar loop needs a heat exchanger with an effectiveness of 0.5. The collector delivers 20,000 BTU/hr and the design temperature difference between the collector fluid and the potable water is 40 F. What minimum UA (heat transfer capacity, BTU/hr-F) must the exchanger provide?

• A1,000 BTU/hr-F
• B500 BTU/hr-F
• C2,000 BTU/hr-F
• D4,000 BTU/hr-F

Why is an expansion tank required in a closed-loop antifreeze solar thermal system?

• ATo accommodate the volume change of the heat-transfer fluid as it heats and cools, keepin…
• BTo store extra antifreeze for topping off the collector loop during routine maintenance
• CTo act as the primary heat exchanger between the antifreeze loop and the potable water
• DTo replace the need for a pressure relief valve on the collector loop

Which freeze-protection method relies on a controller opening a valve to drain collector water into the plumbing whenever freezing is detected, and is generally considered less reliable than drainback or closed-loop antifreeze designs?

• ADraindown (automatic drain valve) system
• BDrainback (reservoir) system
• CClosed-loop propylene glycol system
• DRecirculation warm-water system

When a solar thermal pump stops on a sunny day, the collector can reach very high stagnation temperatures. Which design feature helps protect the collector loop fluid from thermal degradation in this condition?

• AUsing a high-quality propylene glycol formulated for solar stagnation temperatures, combi…
• BAdding more water to the collector loop to absorb the extra heat
• CPainting the collector absorber white to reduce absorption
• DRemoving the glazing so the collector can cool by convection

A solar storage tank routinely stratifies far hotter than a conventional water heater setpoint. Which pair of devices addresses the two distinct hazards that creates?

• AA T&P relief valve to protect the tank against over-temperature and over-pressure, plus a…
• BA T&P relief valve alone, since it both relieves pressure and regulates the temperature d…
• CA cold-inlet check valve plus a thermal expansion tank, which together cap the tank tempe…
• DA differential controller and collector sensor, which shut the system down before the tan…

A collector absorbs 1,000 BTU/hr per ft² under full sun (about 317 BTU/hr per ft² of net useful heat after losses) over a 40 ft² collector. If 12,680 BTU/hr of useful heat is delivered to the tank, what is the system efficiency based on the incident 40,000 BTU/hr of solar energy?

• AApproximately 32 percent
• BApproximately 50 percent
• CApproximately 20 percent
• DApproximately 75 percent

When penetrating a shingle roof to mount solar collectors, which flashing method is most appropriate to prevent water intrusion at the stanchion or bracket?

• AInstall a metal or plastic roof jack/flashing integrated with the underlayment and shingl…
• BApply silicone caulk around the penetration after driving lag bolts through the shingles
• CDrill through the shingle and sheathing with no flashing, relying only on roof sealant ta…
• DCut a large opening in the roof deck and seal it with spray foam only

What is the primary structural purpose of collector mounting standoffs or stanchions attached to the roof rafters?

• ATo transfer the collector wind and gravity loads directly into the roof framing rather th…
• BTo tilt the collector to the optimal angle on a flat roof only
• CTo provide a path for piping and wiring to enter the attic
• DTo act as a gutter to direct rainwater away from the collector

Solar thermal piping exposed outdoors should be insulated and the insulation protected from the environment. What is the standard protection for exterior pipe insulation in a Florida solar installation?

• AA UV-resistant jacket or coating (such as PVC or aluminum jacket) over flexible closed-ce…
• BBare fiberglass batts wrapped loosely with painter's tape
• CNo protection is needed because closed-cell foam is inherently UV-stable for decades
• DA coat of ordinary latex house paint applied once over bare foam

Copper supply and return piping for a rooftop solar collector is run horizontally across an attic. What is a reasonable maximum support spacing for insulated copper piping per common plumbing practice?

• AEvery 6 to 8 feet along the run
• BEvery 2 inches
• CEvery 20 feet or only at turns
• DNo supports are needed in an attic because the piping rests on the ceiling joists

Before installing a solar collector array on a residential roof, which roof characteristic must the contractor verify to ensure the structure can safely carry the added dead load of collectors, fluid, and mounting hardware?

• AThe rafters or trusses are adequately sized and spaced to carry the additional concentrat…
• BThe roof shingle color matches the collector frame
• CThe roof pitch is steeper than 45 degrees
• DThe roof has at least three plumbing vents to balance pressures

Florida building code requires rooftop solar equipment to resist wind uplift. Which installation practice most directly helps meet wind load requirements on a pitched residential roof?

• ALag-bolting mounting stanchions through the roof deck and into the rafter or a structural…
• BSecuring collectors with sheet-metal screws into the roof decking only
• CBallasting the collectors with sandbags placed on the roof around the frame
• DTying the collector frame to the nearest plumbing vent with wire

When mounting a flat-plate collector on a shingle roof, how should the stanchions be spaced along a collector rail to distribute the load?

• AAt intervals specified by the collector and mounting manufacturer, typically every 4 to 6…
• BOnly at the two extreme corners of the collector, with no intermediate supports
• CRandomly wherever a rafter is closest, without regard to manufacturer spacing
• DEvery 10 feet regardless of collector size or manufacturer instructions

A contractor needs to tilt a collector about 20 degrees on a flat low-slope roof to face it south. Which mounting method is appropriate?

• AUse angled rack or triangular support frames anchored to the roof structure or curb, desi…
• BStack wood blocking under the collector bottom edge without fastening
• CBend copper pipe risers to prop the collector up at the desired angle
• DHang the collector from a parapet wall with chain to achieve the tilt

In a multi-collector array, which piping configuration ensures balanced flow through each collector so that no unit is starved or over-fed?

• AReverse-return (supply and return headers arranged so the path length through each collec…
• BSerpentine piping that runs through one collector then the next in series
• CA single supply tee feeding all collectors from one end with returns collected at the opp…
• DRandom tee connections with no consideration of path length

Where should the collector temperature sensor be mounted for a differential controller to accurately reflect the temperature of fluid leaving the collector?

• AStrapped to the collector outlet pipe near the top header, with insulation over the sensor
• BTaped to the collector glazing on the front face in full sun
• CDropped into the storage tank near the heating coil
• DMounted on the roof surface next to the collector frame

A three-collector array uses a reverse-return header. If the target total flow is 3 gpm, what flow should pass through each collector assuming balanced flow?

• A1 gpm per collector
• B3 gpm per collector
• C0.5 gpm per collector
• D2 gpm per collector

Before insulating and commissioning a new solar thermal piping installation, what test should the contractor perform to verify the integrity of all soldered, brazed, and mechanical joints?

• AA hydrostatic pressure test at 1.5 times the working pressure for a prescribed duration,…
• BA visual inspection only, looking for green patina at joints
• CRunning hot water through the system for five minutes and feeling for warmth
• DAn air test with no pressure gauge, listening for hissing sounds

Where should an automatic air vent be installed in a closed-loop solar thermal system to remove trapped air that could block circulation?

• AAt the highest point in the collector loop piping
• BAt the lowest point near the pump suction
• CMidway along the return pipe where it is easiest to reach
• DInside the storage tank at the bottom

A solar storage tank for an indirect system is being installed in a residential garage. Which placement consideration is most important for both performance and code compliance?

• APlace the tank on a load-bearing floor or pad near the backup heater, with a drain pan pi…
• BPlace the tank directly on bare ground outdoors exposed to weather
• CMount the tank horizontally above the ceiling joists to save floor space
• DPlace the tank as far as possible from the existing water heater to maximize pipe length

In a closed-loop antifreeze solar system, where should the expansion tank be installed relative to the pump?

• AOn the suction side of the pump, between the collector return and the pump inlet, where s…
• BOn the discharge side of the pump at the highest point in the loop
• CDirectly inside the collector at the top header
• DAnywhere in the loop, since location does not matter