Current through Register Vol. 50, No. 3, March 20, 2024
A.
Solar energy systems used for heating potable water or using an independent
medium for heating potable water shall comply with the applicable requirements
of this code. The use of solar energy shall not compromise the requirements for
cross connection or protection of the potable water distribution system, water
service pipe, or water supply system required by this code. Solar energy
systems shall also meet the applicable requirements of the state-adopted energy
code and the applicable codes adopted under the authority of Act 12 of the 2005
First Extraordinary Session.
B.
Definitions. Definitions contained in Chapter 2 of this code shall also apply
to this Section except where the following special definitions shall
apply.
Active Solar System - a solar water heating
system that utilizes an electric pump and controllers to circulate heat
transfer fluid through the solar collectors.
Auxiliary Heating Equipment - equipment
utilizing energy other than solar, to supplement the output provided by the
solar energy system.
Closed Loop System - system where the collector loop heat
transfer fluid is enclosed in a piping loop separate from the potable water
supply.
Collector Loop - the piping of a collector
system in which a heat transfer fluid circulates between the
solar collector(s) and a heat exchanger.
Direct-Circulation System - a system where
the potable water is heated as a result of being circulated
directly through the collectors (these systems are prohibited).
Double Wall Heat Exchanger - a heat
exchanger design in which a single failure of any fluid barrier will not cause
a cross connection or permit back siphonage of heat transfer
fluid into the potable water supply. Any barrier
which fails shall allow the discharge of heat transfer fluid
and/or potable water to the atmosphere at a location visible
to the operator or owner.
Drainback System - liquid system that only
fills the collector when the temperature differential is appropriate. The water
that is circulated through the collectors is stored in a reservoir.
Engineered Solar System - a system designed
for a specific building project with drawings and specifications indicating
materials to be installed, all as prepared by a person registered or licensed
to perform solar design work.
Heat Transfer Fluid - the operating or
thermal storage liquid in a mechanical system, including water or other liquid
base, and additives at the concentration present under operating conditions
used to move heat from one location to another. Refrigerants are not included
as heat transfer fluids.
Human Consumption - the use of water by
humans for drinking, cooking, bathing, showering, hand washing, dishwashing, or
maintaining oral hygiene.
IAF - International Accreditation Forum,
the world association of Conformity Assessment Accreditation Bodies and other
bodies interested in conformity assessment in the fields of management systems,
products, services, personnel and other similar programs of conformity
assessment. Its primary function is to develop a single worldwide program of
conformity assessment which reduces risk for business and its customers by
assuring them that accredited certificates may be relied upon. Accreditation
assures users of the competence and impartiality of the body accredited.
IAF MLA Signatory - The objective of the
IAF MLA is to ensure that the personnel certifications granted
by signatories of the IAF MLA can be recognized by other
signatories, increasing the worldwide employability of the certified
professionals. Mutual recognition is based on peer evaluations between
signatories to ensure each other's personnel certifications are equivalent and
that each certified professional can perform the required tasks. Once an
accreditation body is a signatory of the IAF MLA it is
required to recognize the certificates issued by conformity assessment bodies
accredited by all other signatories of the IAF MLA, with the
appropriate scope. Accreditations granted by IAF MLA
signatories are recognized worldwide based on their equivalent accreditation
programs, therefore reducing costs and adding value to business and consumers.
Accreditation body members of IAF are admitted to the
MLA only after stringent evaluation of their operations by a
peer evaluation team. For a complete list of IAF members and
signatories visit:
http://www.iaf.nu/articles/
IAF_MEM_USA__all/112.
IECI - International Electrotechnical
Commission.
Indirect-Circulation System - a
closed loop solar water heating system which prohibits contact
between the heat transfer fluid and the potable water by the
use of a heat exchanger to transfer the collected heat from the heat transfer
fluid to the potable water.
ISO - International Organization for
Standardization.
ISO/IEC Guide 65 - a document that
specifies requirements for bodies that operate third-party certifications of
products to ensure that those bodies conduct their certification processes in
an impartial, reliable, and consistent manner. Conformity to these standards
provides assurance that a certification program is of high quality, integrity,
and competency, and that it is free of any conflicts of interest, such as
financial, commercial, or social influences.
Listed - equipment or materials included in
a list published by an approved nationally recognized testing laboratory,
inspection agency or other organization concerned with product evaluation that
maintains periodic inspection of production of listed equipment or materials,
and whose listing states either that the equipment or material meets nationally
recognized standards or has been tested and found suitable for use in a
specified manner. The means for identifying listed equipment may vary for each
testing laboratory, inspection agency, or other organization concerned with
product evaluation, some of which do not recognize equipment as listed unless
it is also labeled. The plumbing official should utilize the system employed by
the listing organization to identify a listed product.
MLA - Multilateral Recognition Arrangement,
to ensure mutual recognition of accredited certification between signatories to
the MLA, and subsequently acceptance of accredited
certification in many markets based on one accreditation.
Potable Water - water having
bacteriological, physical, radiological and chemical qualities that make it
safe and suitable for human consumption.
Potable Water Supply - a publicly owned or
privately owned water supply system which purveys potable
water.
Readily Accessible - having direct access
without the need of removing any panel, door or similar covering of the item
described and without requiring the use of portable ladders, chairs,
etc.
Solar Collector - a device designed to
absorb radiation from the sun and transfer this energy to a fluid which passes
through the collector.
Solar Water Heating System - any unit or
package of components designed to collect, convey, store, and convert the sun's
energy for the purpose of heating potable water
SRCC - Solar Rating and Certification
Corporation
Toxic - a substance that causes injury,
illness, or death, especially by chemical means.
C. General. The following general
requirements shall be applicable to solar water heating systems.
1. Certification. Solar water heating systems
shall be certified to the Solar Rating and Certification Corporation's (SRCC)
OG-300 document, 2010 edition (Operating Guidelines and Minimum Standards for
Certifying Solar Water Heating Systems) by the SRCC themselves or by listing
agencies [such as the International Association of Plumbing and Mechanical
Officials (IAPMO)] which are currently accredited as meeting the ISO/IEC Guide
65 by the American National Standards Institute (ANSI) or other IAF MLA
signatory accreditation bodies.
2.
Installation. Solar water heating systems and appurtenances shall comply with
the requirements of this Section, other applicable provisions of this code, and
any other applicable requirements of the codes adopted under the authority of
Act 12 of the 2005 First Extraordinary Session. All parts of a solar water
heating system involving plumbing shall be installed by individuals holding a
valid plumber's license issued by the State Plumbing Board of Louisiana
(SPBLA), subject to any exceptions thereto as may be authorized under the
SPBLA's law and regulations.
a. Solar water
heating systems shall be installed in a manner conforming to this Section,
other applicable provisions of this code, applicable standards, and the
manufacturers' installation instructions. In instances where this Section,
other applicable provisions of this code, applicable standards, or the
manufacturers' instructions conflict, the more stringent provisions shall
prevail.
3. Maintenance.
Solar water heating systems shall be maintained in proper safe and sanitary
operating condition, and the owner shall be responsible for maintenance.
a. Access for maintenance and repair shall be
provided to solar water heating system equipment, components, valves, etc.
Solar water heating equipment and appurtenances shall not obstruct or interfere
with the operation of any doors, windows, or other building components
requiring operation or access.
4. Safety. Any solar water heating system
capable of providing hot water in excess of 140° F (60°C) shall be equipped
with a listed tempering valve or temperature-limiting device to limit the
temperature of water delivered to the domestic hot water system to a maximum of
140° F (60°C).
a. Solar water heating
equipment that could generate a glow, spark, or flame capable of igniting
flammable vapors may be installed in a residential garage provided the pilots
and burners, heating elements, motors, controllers, or switches are at least 18
inches (457 mm) above the floor level.
D. Solar Water Heating System Design
Criteria. Solar water heating system design criteria shall be as follows.
1. Overall System Design. All solar water
heating systems shall be of the closed loop type, utilizing an indirect
circulation system. Direct circulation systems are prohibited.
a. Solar water heating systems shall have
flow directions indicated on system components and piping or shall have flow
directions indicated on a diagrammatic representation of the system as
installed, permanently affixed to the system hardware in a readily accessible
and visible location.
b. The solar
water heating system shall be valved to provide for shut-off from the service
water supply without interrupting normal cold water service to the residence
(see §509. A of this code and apply).
2. Freeze Protection. Solar water heating
system components shall be protected from damage resulting by freezing of heat
transfer liquids at the lowest ambient temperatures that will be encountered
during the operation of the system.
a. Solar
water heating systems, where the design requires piping to be drained to
protect the system from freezing, or where the heat transfer fluid must be
replaced as part of regular maintenance, shall have all piping pitched toward a
designated point in the system to accomplish the intended purpose.
3. Temperature and Pressure. Solar
water heating system components (i.e., solar collector, storage tank, heat
exchanger, piping) containing pressurized fluids shall be protected against
pressures and temperatures exceeding design limitations with a properly
installed temperature and pressure (T and P) relief valve. Each section of the
system in which excessive temperatures and pressures are capable of developing
shall have a T and P relief valve located so that a section cannot be valved
off or otherwise isolated from protection by a properly installed a T and P
relief valve.
a. Relief valves and its
discharge piping and appurtenances shall meet the requirements listed in §511.
E through 511.H.5 of this code.
b.
Vacuum relief valves shall be installed at the high point of the solar system
for drain back systems unless specifically not required by the system
design.
4. Thermal
Contraction and Expansion. The solar water heating system design, components
and subassemblies shall include adequate provisions for the thermal contraction
and expansion of heat transfer fluids and system components that will occur
over the design temperature range.
a.
Provisions for thermal contraction and expansion within the potable water
system shall be installed in accordance with the requirements of §623. D of
this code, as it relates to the water being heated for consumer use.
5. Solar Collectors. Collectors
that are manufactured as a complete component shall be listed by a recognized
third party listing agency. Collectors shall be listed and labeled to show the
manufacturer's name, model number, serial number, collector weight, collector
maximum allowable temperatures and pressures, and the type of heat transfer
fluids that are compatible with the collector. The label shall clarify that
these specifications apply only to the collector.
a. Valves shall be installed to allow the
solar collectors to be isolated from the remainder of the solar water heating
system. Each isolation valve shall be labeled with the open and closed
position.
b. Collectors shall be
anchored to roof structures or other surfaces in a manner to resist wind, snow,
or seismic loadings in compliance with the applicable(s) codes adopted under
the authority of Act 12 of the 2005 First Extraordinary Session. Anchors
secured to and through a roofing material shall be made in a manner to maintain
the water integrity of the roof covering. Roof drainage shall not be impaired
by the installation of collectors. Collector panels that are not an integral
part of the roofing system shall be installed in a manner so as to preserve the
integrity of the roof surface.
6. Heat Exchangers. Heat exchangers used for
potable water heating shall protect the potable water system from being
contaminated by the heat transfer fluid.
a.
Heat exchangers that are of double-walled construction shall be utilized that
separate the potable water from the heat transfer fluid by providing a space
between the two walls that is vented to the atmosphere. The heat exchanger
design shall be such that any failure of a barrier material shall allow the
discharge of exchanger fluid and/or potable water to the atmosphere. The
discharge location shall be visible to the operator or owner of the system and
be located so that no hazards are created by such discharge.
b. Single-walled heat exchangers are
prohibited.
7. Heat
Transfer Fluid. Heat transfer fluid shall be compatible with all materials in
the system. The flash point of the actual heat transfer fluid utilized in a
solar water heating system shall be not less than 50°F (10°C) above the design
maximum stagnation (no-flow) temperature of the fluid attained in the
collector.
a. Only non-toxic fluids shall be
utilized as the heat transfer fluid, including additives, such as anti-freeze
agents, conditioners, or corrosion inhibitors.
8. Storage or Heat Exchanger Tank
Construction. All tanks shall be tested and listed by an approved agency.
Pressurized thermal storage units shall be listed and labeled to show the
manufacturer's name, model number, serial number, storage unit maximum and
minimum allowable operating temperatures and pressures, and the type of heat
transfer fluids that are compatible with the storage unit. The label shall
clarify that these specifications apply only to the thermal storage unit.
a. Tank covers shall be structurally designed
to withstand all anticipated loads and pressures.
b. All devices attached to or within the tank
shall be accessible for repair and replacement.
9. Auxiliary Heating System. Auxiliary water
heating equipment shall be provided such that the combined system (i.e., solar
water heating system and the auxiliary water heating equipment) will provide
the same degree of reliability and performance as a conventional water heating
system.
a. Auxiliary (non-solar) water
heating equipment shall be compatible with the solar system heat output,
temperatures, flow rates and fluid types. Auxiliary water heating equipment
shall be listed and labeled by a recognized third party listing
agency.
b. The piping system shall
be provided with valves which can be closed for the purpose of isolating the
solar hot water heating system from the auxiliary water heater, thereby
permitting operation of the auxiliary water heating system when the solar water
heating system is inoperative or being serviced.
c. Auxiliary water heaters shall meet all
applicable requirements set forth in this Chapter.
E. Potable Water Supply. The
potable water supply shall be protected from an actual or potential cross
connection to any nonpotable water piping by having any nonpotable water piping
(e.g., heat transfer fluid piping) color coded/identified in
accordance with
§607 of this code.
F. Materials. Subject to any additionally
limitations below, all plumbing used in the solar water heating system
including, but not limited to the collector loop, shall consist of the water
distribution pipe, tubing and fittings materials specified in
§619 of this code. Such materials shall
comply with the standards listed in Table 603 of this code.
1. All hard-drawn copper tubing, in addition
to the required incised marking, shall be marked in accordance with Sections
19.3 1 and 19.3.2 of ASTM B88-99 Standard Specification for Seamless
Copper Water Tube. The colors shall be: Type K, green; Type L, blue.
(Please note that Type M is not approved for plumbing uses in
Louisiana).
2. Cast-iron fittings
up to and including 2 inches in size, when used in connection with piping,
shall be galvanized.
3. All
malleable iron fittings shall be galvanized.
4. Flexible corrugated water heater
connectors of copper or stainless steel shall be limited to 24 inches in
length.
5. PEX tubing shall not be
installed within the first 18 inches of piping connected to a water
heater.
6. In no case shall plastic
pipe including, but not limited to chlorinated polyvinyl chloride (CPVC) pipe
and fittings, be used in a collector loop.
7. The piping of the collector loop shall be
insulated to a minimum R-value of 2.6.
G. Testing. Testing of solar water heating
systems and its components shall be performed in accordance with the following.
1. Closed Loop System. Closed loop or other
type pressure systems shall be tested at one and one-half times maximum
designed operating pressure. All systems shall withstand the test without
leaking for a period of not less than 15 minutes.
2. Storage Tanks. Storage tanks associated
with solar water heating systems shall be tested in accordance with the
following.
a. Pressure type storage tanks
shall be tested as prescribed in §513. G.1 of this code above.
b. Non-pressure type storage tanks shall be
tested by filling it with water for a period of 24 hours prior to inspection
and shall withstand the test without leaking. No tank or portion thereof shall
be covered or concealed prior to approval.
H. Abandonment. Every abandoned solar water
heating system or part thereof shall be physically disconnected from any
remaining part of the plumbing system, drained, and plugged or capped in an
approved manner.
AUTHORITY NOTE:
Promulgated in accordance with
R.S.
40:4(A)(7) and
R.S.
40:5(2)(3)(7)(9)(16)(17)(20).
