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SPS 371.23(3)(c) (c) Glass. Glass used in collector construction shall be tempered.
SPS 371.23(3)(d) (d) Glazings. Glazings subject to human impact and within 7 feet of ground level shall be safety glazing material constructed, treated or combined with other materials so as to minimize the likelihood of cutting and piercing injuries resulting from human impact with the glazing material.
SPS 371.23(3)(e) (e) Plastic. Plastic used in collector construction shall be capable of withstanding the maximum operating pressure and temperature, and shall be used in accordance with manufacturer's recommendations.
SPS 371.23(3)(f) (f) No-flow. The collector shall be capable of withstanding no-flow conditions.
SPS 371.23(3)(g) (g) Leakage. The construction of the collector shall provide protection against:
SPS 371.23(3)(g)1. 1. External leakage of the heat transfer fluid from the collector;
SPS 371.23(3)(g)2. 2. Internal leakage into the collector from environmental conditions; and
SPS 371.23(3)(g)3. 3. Internal leakage of the heat transfer fluid from the collector from cleaning operations as performed during routine maintenance as specified in the operation and maintenance manual.
SPS 371.23(3)(h) (h) Corrosion.
SPS 371.23(3)(h)1.1. All materials used in the absorber or heat transfer fluid conduits may not be pitted, corroded, or otherwise degraded by the heat transfer fluid to an extent that will result in failure during its design life.
SPS 371.23(3)(h)2. 2. In closed loop systems, aluminum may not be connected with copper or iron. Separation of different pipe materials by isolating bushings is not acceptable.
SPS 371.23(3)(i) (i) Ultraviolet stability. All materials used in the collector may not degrade when exposed to ultraviolet radiation to an extent that will reduce the collector performance below the declared collector performance.
SPS 371.23(3)(j) (j) Insulation. Collector insulation shall be capable of withstanding moisture, ultraviolet radiation, and environmental exposure.
SPS 371.23(4) (4)Collector mounting and installation.
SPS 371.23(4)(a)(a) Mounting.
SPS 371.23(4)(a)1.1. `Mounting on roofs.' Load design requirements shall be in accordance with s. SPS 371.21 (7).
SPS 371.23(4)(a)2. 2. `Mounting on the ground.' When collectors are located on concrete slabs, the slab shall be a minimum of 4 inches thick. Collectors shall be located a minimum of 6 inches above the ground surface. Collectors installed on the ground shall be adequately supported and anchored.
SPS 371.23(4)(a)3. 3. `Collector stresses.' Structural supports may not impose undue stresses on the collector.
SPS 371.23(4)(a)4. 4. `Wood.' All wood components used in collector mounting which are exposed to the environment shall be resistant to decay in accordance with s. SPS 371.21 (4) (d). Wood used in collector frames or housings shall be protected against structural degradation due to high temperature exposure.
SPS 371.23(4)(a)5. 5. `Metal.' All metal parts shall be protected from environmental conditions in accordance with s. SPS 371.22 (7) (b) and (c).
SPS 371.23(4)(a)6. 6. `Tilt and orientation.' Structural supports shall be constructed to maintain collector tilt and orientation within design conditions throughout the life of the solar energy system.
SPS 371.23(4)(b) (b) Installation.
SPS 371.23(4)(b)1.1. `Instructions.' Collectors shall be installed in accordance with the instructions provided by the system designer.
SPS 371.23(4)(b)2. 2. `Fire protection.' Collectors made of combustible materials may not be located on or adjacent to construction required to be of noncombustible materials. Collector installation shall also comply with s. SPS 371.21 (6).
SPS 371.23(4)(b)3. 3. `Safety.' Safe access to components subject to deterioration or failure, such as rubber hoses, joint sealants, and cover plates, shall be provided to allow for maintenance or repair. For roof-mounted collectors, the work space adjacent to collectors and provisions for safe placement of ladders shall be considered.
SPS 371.23(4)(b)4. 4. `Moisture protection.' Collector installation may not contribute to moisture buildup, rotting, or other accelerated deterioration of roofing materials. Collectors and structural supports shall be installed in a manner such that water flowing off the collector surface and structural supports will not accelerate formation of ice dams or cause water damage to the building or dwelling. Provisions shall be taken to minimize buildup of snow upon collectors, which may reduce their effectiveness.
SPS 371.23(4)(b)5. 5. `Caulking and sealing.' Joints between structural supports and buildings or dwellings shall be caulked and flashed to prevent water leakage. Bolts or other means of fastening the collector or structural supports to the roof shall be sealed from water penetration.
SPS 371.23(4)(b)6. 6. `Filling and draining.' Interconnecting piping or ducting shall be installed to minimize flow restrictions and to provide balanced flow. Piping shall be installed to allow for filling and draining.
SPS 371.23 History History: Cr. Register, June, 1986, No. 366, eff. 7-1-86; correction in (4) (a) 1., 4., 5., (b) 2. made under s. 13.92 (4) (b) 7., Stats., Register December 2011 No. 672.
SPS 371.24 SPS 371.24Air systems. This section shall apply to active solar energy systems and components that use air as a heat transfer fluid.
SPS 371.24(1) (1)Air distribution.
SPS 371.24(1)(a)(a) Size. Air distribution components shall be adequately sized to insure a uniform distribution of air.
SPS 371.24(1)(b) (b) Dust and dirt prevention.
SPS 371.24(1)(b)1.1. `Flow efficiency and health hazard.' Duct and fan systems shall be protected against accumulation of deposits of dust or dirt that could reduce flow and efficiency or create a potential health hazard when admitted into occupied spaces.
SPS 371.24(1)(b)2. 2. `Air filters'. Air filters shall be installed on the outlet side of the thermal storage in solar energy systems. Air filters shall be removable to allow cleaning. Solar energy systems used for space heating shall incorporate the use of a high efficiency air filter installed in the cold air riser duct to the collectors unless the air does not pass over the absorber.
SPS 371.24(1)(c) (c) Insulation. The primary solar duct system shall be insulated as specified in s. SPS 371.21 (3).
SPS 371.24(1)(d) (d) Ductwork.
SPS 371.24(1)(d)1.1. `Interior ducts'. Interior ducts shall comply with chs. SPS 320 to 325 for one- and 2-family dwellings or chs. SPS 361 to 366 for commercial buildings.
SPS 371.24(1)(d)2. 2. `Exterior ducts'. Ducts located outside the dwelling or building shall be constructed of galvanized steel or corrosion-resistant metal.
SPS 371.24(1)(e) (e) Temperature, pressure and exposure. Ducts, insulation, gaskets, sealants and adhesives shall be capable of withstanding maximum operating temperatures, pressures and environmental exposure.
SPS 371.24(1)(f) (f) Bypass. Solar energy systems providing both space heating and domestic water heating shall be equipped with a bypass of the thermal storage during the nonheating season.
SPS 371.24(2) (2)Sealing of air systems.
SPS 371.24(2)(a)(a) Duct system. The primary solar duct system shall be sealed in accordance with the following requirements:
SPS 371.24(2)(a)1. 1. All joints in metal ducts shall be made with good fit-up and closure.
SPS 371.24(2)(a)2. 2. Joints and seams shall be sealed with adhesives, mastics or compatible combinations of tape binders and adhesives in ducts conveying air to and from storage units and solar collectors and in ducts conveying air from such circuits to points of connections with ducts circulating air to and from the occupied space.
SPS 371.24(2)(a)3. 3. Tapes shall be used in accordance with manufacturer's recommendations.
SPS 371.24(2)(a)4. 4. Oil-base caulking and glazing compounds may not be used.
SPS 371.24(2)(a)5. 5. Stapled closures of duct connections and stapled fitting assemblies shall be sealed.
SPS 371.24 Note Note: The purpose of these requirements is to reduce the duct loss to 10% or less. It is not the intent to require testing of the installed system to determine duct leakage, but to assure construction standards which will essentially provide the required degree of airtightness in the primary solar duct system. Construction which will provide equivalent airtightness will be allowed in lieu of the sealing requirements.
SPS 371.24(2)(b) (b) Thermal storage. Thermal storage shall be constructed and sealed or otherwise fabricated to limit air leakage. Sealing shall include joints in thermal storage, duct and access openings.
SPS 371.24 Note Note: This is not intended to apply to thermal storage which is thermally coupled to heated spaces. Concrete should be considered potentially porous and may require lining and sealing to limit air leakage. Problems associated with shrinking, warping and cracking should be considered for thermal storage constructed of wood.
SPS 371.24(2)(c) (c) Collectors and components. Collectors and other components, such as air handling units, heat exchangers and filters, shall be assembled and sealed in accordance with manufacturer's and system designer's instructions. Sealing shall include all joints between components and ducts. Equivalent airtightness shall be provided for site-built collectors.
SPS 371.24(3) (3)Freeze protection.
SPS 371.24(3)(a)(a) Cold airflow prevention. The solar energy system shall be designed and installed to prevent cold airflow across the water heater coil. If mechanical dampers are used to meet this requirement, they shall not allow leakage of more than 5% of the solar energy system design airflow rate at one-inch water column.
SPS 371.24(3)(b) (b) Secondary freeze protection. Solar energy systems using electrical or mechanical devices for freeze protection, shall incorporate a secondary freeze protection system in case of mechanical failure. An electrical freeze sensor which activates the pump to circulate fluid through the water heater coil may be used to meet this requirement.
SPS 371.24(3)(c) (c) Nonautomatic freeze protection. Any nonautomatic freeze protection shall be noted as such in the operation and maintenance manual.
SPS 371.24(4) (4)Thermal storage.
SPS 371.24(4)(a)(a) Air quality. Heat transfer fluid, heat storage media and thermal storage materials, including any interior protective coating, may not impart toxic elements or offensive odors to air distributed to areas of human occupancy.
SPS 371.24(4)(b) (b) Insulation. Thermal storage shall be insulated in accordance with s. SPS 371.21 (3).
SPS 371.24(4)(c) (c) Loads and environmental conditions. Loads shall meet the requirements of s. SPS 371.21 (7). Thermal storage located outside or underground shall be waterproof.
SPS 371.24(4)(d) (d) Rock storage. When rock is utilized for thermal storage, the rock shall be cleaned and dried before it is placed into the storage area. The thermal storage shall be provided with an inlet and an outlet plenum.
SPS 371.24(4)(e) (e) Phase change. If phase change storage materials are used, they shall be placed in sealed containers.
SPS 371.24(5) (5)Dampers.
SPS 371.24(5)(a)(a) Volume control dampers shall be installed in each branch or zone duct. Single leaf dampers which are a part of a manufactured air grille may not be used.
SPS 371.24(5)(b) (b) Opposed blade dampers which are a part of a manufactured air grille shall be acceptable if sufficient space is provided behind the grille face for proper operation of the damper. Where space prohibits the use of an opposed blade damper behind the grille face, an opposed blade damper may be installed in the register stack at a location where it is accessible from the grille opening.
SPS 371.24(5)(c) (c) Volume control dampers shall be of a type and size that will satisfy the design conditions of the duct system.
SPS 371.24(5)(d) (d) Backdraft dampers or motorized dampers shall be installed so as to prevent air passage through the collectors when solar energy is not being collected.
SPS 371.24(5)(e) (e) Dampers installed in the primary solar duct system shall have felted blade edges or otherwise be treated to insure tight cutoff of the airstream.
SPS 371.24(5)(f) (f) Volume control dampers shall be furnished with a locking control device to hold the damper in its fixed control position unless the damper is motor controlled.
SPS 371.24(6) (6)Blowers.
SPS 371.24(6)(a)(a) Blowers shall be of a type and size that will satisfy the design conditions of the solar energy system.
SPS 371.24(6)(b) (b) All blowers shall be rated by the manufacturers in cfm capacity against a specific external static pressure.
SPS 371.24 History History: Cr. Register, June, 1986, No. 366, eff. 7-1-86; CR 01-139: am. (1) (d) 1. Register June 2002 No. 558, eff. 7-1-02; correction in (1) (c), (d) 1., (4) (b), (c) made under s. 13.92 (4) (b) 7., Stats., Register December 2011 No. 672.
SPS 371.25 SPS 371.25Liquid systems. This section shall apply to active solar energy systems and components that use liquid as a heat transfer fluid.
SPS 371.25 Note Note: The connection of a solar energy system to the potable water supply system may require the obtaining of a local plumbing permit.
SPS 371.25(1) (1)Liquid distribution.
SPS 371.25(1)(a)(a) Design. Components shall be designed for flow rates, temperatures, pressures, mechanical stresses, material properties and heat transfer fluid characteristics to provide proper and efficient performance.
SPS 371.25(1)(b) (b) Pipe.
SPS 371.25(1)(b)1.1. `Size.' Pipe sizing shall be in accordance with accepted design practice or recognized methods.
SPS 371.25 Note Note: The sizes of pipe to be used for mains and risers may be selected from the ASHRAE Guide and Data Book, published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers; or from the manuals published by The Hydronics Institute, 35 Russo Place, Berkely Heights, New Jersey 07922 or the Mechanical Contractors Association of America, 5410 Grosvenor Lane, Suite 120, Bethesda, Maryland 20814.
SPS 371.25(1)(b)2. 2. `Pipe materials.' Piping materials for open loop systems shall comply with s. SPS 384.30. Piping materials for closed loop systems shall be schedule 40 black pipe, type K, L or M copper, or other pipe approved by the department. Unglazed, nonconcentrating collectors, limited to unpressurized systems for swimming pool and spa heating applications, with a maximum operating temperature of 200ºF, may utilize rubber or plastic plates and piping.
SPS 371.25(1)(b)3. 3. `Draining and filling.' Where the design requires piping to be drained to protect the solar energy system from freezing or where the heat transfer fluid must be replaced as part of regular maintenance, the piping shall be pitched toward a designated point in the solar energy system to permit drainage. Appropriate valving to drain and fill the solar energy system shall also be supplied.
SPS 371.25(1)(b)4. 4. `Hangers and supports'. Pipe hangers and supports shall be in accordance with s. SPS 382.60.
SPS 371.25(1)(b)5. 5. `Identification of potable and nonpotable water.' The identification of potable and nonpotable water piping systems shall be in accordance with s. SPS 382.40 (3) (b).
SPS 371.25(1)(b)6. 6. `Insulation.' Piping shall be insulated in accordance with s. SPS 371.21 (3).
SPS 371.25(1)(c) (c) Valves.
SPS 371.25(1)(c)1.1. Relief valves shall be designed and installed in accordance with s. SPS 371.22 (3).
SPS 371.25(1)(c)2. 2. All required shutoff or control valves shall be readily accessible.
SPS 371.25(1)(c)3. 3. Valves used to charge or drain closed loop systems shall be the loose-key type, have valve outlets capped or have handles removed when the solar energy system is operational.
Published under s. 35.93, Stats. Updated on the first day of each month. Entire code is always current. The Register date on each page is the date the chapter was last published.