ASTM E1160-13(2021)

Standard Guide for On-Site Inspection and Verification of Operation of Solar Domestic Hot Water Systems

SIGNIFICANCE AND USE
4.1 This guide is intended for on-site assessment of in-service operation by short term measurement of appropriate system functions under representative operating conditions.  
4.2 Primary application is for residential systems and medium-size multi-family units or commercial buildings. Use of back-up conventional DHW heating system is assumed to augment solar heating.  
4.3 This guide is intended for use by suppliers, installers, consultants and homeowners in evaluating on-site operation of an installed system. Emphasis is placed on simplified measurements that do not require special skills, intrusive instrumentation, system modification or interruption of service to the purchaser.  
4.4 The purpose of this guide is to verify that the system is functioning. Copies of all data and reports must be submitted by the testing group to the owner or his or her designated agent.  
4.5 Data and reports from these procedures and tests may be used to compare the system performance over time, but should not be used to compare different systems or installations.  
4.6 Test is for a newly installed system and also for periodic checking.
SCOPE
1.1 This guide covers procedures and test methods for conducting an on-site inspection and acceptance test of an installed domestic hot water system (DHW) using flat plate, concentrating-type collectors or tank absorber systems.  
1.2 It is intended as a simple and economical acceptance test to be performed by the system installer or an independent tester to verify that critical components of the system are functioning and to acquire baseline data reflecting overall short term system heat output.  
1.3 This guide is not intended to generate accurate measurements of system performance (see ASHRAE standard 95-1981 for a laboratory test) or thermal efficiency.  
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Dec-2020
• ICS: 27.160 - Solar energy engineering
• Technical Committee: E44 - Solar, Geothermal and Other Alternative Energy Sources
• Drafting Committee: E44.20 - Optical Materials for Solar Applications

Relations

• Refers: ASTM E1056-85(2007) - Standard Practice for Installation and Service of Solar Domestic Water Heating Systems for One- and Two-Family Dwellings
• Effective Date: 01-Mar-2007
• Refers: ASTM E1056-85(2001) - Standard Practice for Installation and Service of Solar Domestic Water Heating Systems for One- and Two-Family Dwellings
• Effective Date: 22-Feb-1985
• Refers: ASTM E823-81(2001) - Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)
• Effective Date: 29-May-1981

Overview

ASTM E1160-13(2021): Standard Guide for On-Site Inspection and Verification of Operation of Solar Domestic Hot Water Systems provides comprehensive procedures for assessing and verifying the operation of installed solar domestic hot water (SDHW) systems. This standard is designed for short-term, on-site inspections under representative operating conditions, focusing on the system’s critical component functionality and overall short-term heat output.

ASTM E1160-13(2021) aims to facilitate performance verification without specialized skills, intrusive instrumentation, or system modifications. It serves as an essential reference for suppliers, installers, consultants, and homeowners seeking to ensure that solar hot water systems are installed correctly and operating as intended in residential, multifamily, and commercial settings.

Key Topics

• On-Site Inspection Procedures: Step-by-step guidance for visually and functionally checking critical system components, including collectors, controls, sensors, pumps, and valves, with emphasis on straightforward, low-intrusion approaches.
• Verification of Operation: Methods for confirming that the solar domestic hot water system is functioning, including simplified measurements of temperature, flow rates, and system response under real-world conditions.
• Test Categories: Recommendations for test complexity:
  • Category A: Basic visual inspections.
  • Category B: Simple tests requiring minimal instrumentation.
  • Category C: More detailed procedures involving advanced instruments, if needed.
• Data Reporting: Requirements for recording and submitting all test data and inspection reports to system owners or their designated agents for ongoing system documentation.
• Safety Considerations: Users must ensure compliance with relevant safety, health, and environmental practices during inspection and testing.

Applications

ASTM E1160-13(2021) offers practical value in various scenarios, including:

• New Installations: Serving as an acceptance test to verify that a newly installed solar domestic hot water system is correctly installed and operating according to specifications.
• Periodic System Checks: Providing procedures for routine inspections to detect malfunctions, performance degradation, or maintenance needs, supporting long-term system reliability.
• Performance Baseline Establishment: Acquiring initial operational data to serve as a benchmark for future performance comparisons of the same system.
• Non-Invasive Assessment: Enabling verification and monitoring without requiring system shutdown, invasive modifications, or temporary discontinuation of service, thus minimizing disruption.
• For Residential and Commercial Use: Applicable to single-family homes, multi-family units, and commercial buildings that utilize flat plate collectors, concentrating collectors, or tank absorber systems with supplemental conventional water heaters.

Related Standards

The guide references several key documents that complement and extend its procedures, including:

• ASTM E1056: Practice for Installation and Service of Solar Domestic Water Heating Systems.
• ASHRAE 93-1986 / ANSI B198.1-1977: Methods for testing solar collector performance.
• ASHRAE 95-1981: Laboratory testing standards for domestic hot water systems.
• NIST 76-1137: Requirements and procedures for system instrumentation and performance evaluation.
• ISO 9806: International test methods for solar collectors.
• ASTM E823: Practice for non-operational exposure and inspection of solar collectors.

By adhering to ASTM E1160-13(2021), industry professionals can ensure consistent, reliable, and documented operation of solar domestic hot water systems, supporting increased adoption of solar water heating technology and contributing to energy efficiency in the built environment.

Keywords: ASTM E1160, solar domestic hot water system, on-site inspection, solar water heating verification, collector operation, system acceptance test, performance monitoring, freeze protection, residential solar hot water, commercial solar water systems, SDHW standards.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:E1160 −13 (Reapproved 2021)
Standard Guide for
On-Site Inspection and Verification of Operation of Solar
Domestic Hot Water Systems
This standard is issued under the fixed designation E1160; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope of a Solar Collector (Withdrawn 2010)
E1056Practice for Installation and Service of Solar Domes-
1.1 This guide covers procedures and test methods for
tic Water Heating Systems for One- and Two-Family
conducting an on-site inspection and acceptance test of an
Dwellings
installed domestic hot water system (DHW) using flat plate,
2.2 ASHRAE Standards:
concentrating-type collectors or tank absorber systems.
93-1986(ANSI B198.1-1977) Method of Testing to Deter-
1.2 Itisintendedasasimpleandeconomicalacceptancetest 4
mine the Thermal Performance of Solar Collectors
tobeperformedbythesysteminstalleroranindependenttester
95-1981Method of Testing to Determine the Thermal Per-
toverifythatcriticalcomponentsofthesystemarefunctioning 4
formance of Domestic Water Heating System
and to acquire baseline data reflecting overall short term
2.3 NIST Standard:
system heat output.
76-1137 Thermal Data Requirements and Performance
1.3 Thisguideisnotintendedtogenerateaccuratemeasure-
Evaluation Procedures for the National Solar Heating and
ments of system performance (seeASHRAE standard 95-1981
Cooling Demonstration Program
for a laboratory test) or thermal efficiency.
2.4 ISO Standard:
9806Test Methods for Solar Collectors
1.4 The values stated in SI units are to be regarded as the
standard. The values given in parentheses are for information
3. Summary of Guide
only.
3.1 This guide recommends inspection procedures and tests
1.5 This standard does not purport to address all of the
for: general system inspection, collector efficiency, freeze
safety concerns, if any, associated with its use. It is the
protection, and controller and pump/blower operation.
responsibility of the user of this standard to establish appro-
3.1.1 Verification of satisfactory operation of these compo-
priate safety, health, and environmental practices and deter-
nents indicates that the system is functioning. Tests are
mine the applicability of regulatory limitations prior to use.
designedtotakeaminimumoftimeinpreparation,testingand
1.6 This international standard was developed in accor-
restorationofthesystem.Theymayuserelativelyinexpensive,
dance with internationally recognized principles on standard-
nonintrusive instrumentation which system installers can rea-
ization established in the Decision on Principles for the
sonably be expected to have on hand.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical 3.2 Recommended tests for each component or subsystem
Barriers to Trade (TBT) Committee. fall into categories according to the level of complexity and
cost (Note 1).
2. Referenced Documents
3.2.1 Category A—The most rudimentary tests, such as
visual inspection.
2.1 ASTM Standards:
3.2.2 Category B—Tests that require minimal instrumenta-
E823Practice for Nonoperational Exposure and Inspection
tion and skill.
3.2.3 Category C—Tests that require most expensive or
1 sophisticated instrumentation or more time to perform.
This guide is under the jurisdiction of ASTM Committee E44 on Solar,
GeothermalandOtherAlternativeEnergySourcesandisthedirectresponsibilityof
Subcommittee E44.20 on Optical Materials for Solar Applications.
Current edition approved Jan. 1, 2021. Published January 2021. Originally The last approved version of this historical standard is referenced on
approved in 1987. Last previous edition approved in 2013 as E1160–13. DOI: www.astm.org.
10.1520/E1160-13R21. Available from ASHRAE, 1791 Tullie Circle, N.E., Altanta, GA 30329.
2 5
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from National Institute of Standards and Technology, Gaithersburg,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM MD 20899.
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1160−13 (2021)
NOTE 1—Category B tests should include Category A tests as
4. Significance and Use
prerequisite, etc.
4.1 This guide is intended for on-site assessment of in-
3.2.4 Selection of the appropriate test is at the discretion of
service operation by short term measurement of appropriate
the tester and purchaser, who should be aware of the tradeoffs
system functions under representative operating conditions.
between cost and accuracy at each level of testing. The tester
should make these clearly known to the purchaser of the 4.2 Primary application is for residential systems and
system who may wish to assume the costs of more sophisti- medium-size multi-family units or commercial buildings. Use
cated testing (Note 2). Preferably there should be a part of the of back-up conventional DHW heating system is assumed to
installation contract between the tester and purchaser spelling augment solar heating.
out test specifics (for example, Category A, B or C for each
4.3 This guide is intended for use by suppliers, installers,
subtest).
consultants and homeowners in evaluating on-site operation of
NOTE 2—Consult your local National Balancing Bureau or Associated aninstalledsystem.Emphasisisplacedonsimplifiedmeasure-
Air Balance Council.
ments that do not require special skills, intrusive
3.3 Instrumentation includes sensors to monitor some or all instrumentation, system modification or interruption of service
of the following conditions: to the purchaser.
3.3.1 Total incident solar radiation (in the plane of the
4.4 The purpose of this guide is to verify that the system is
collector array),
functioning. Copies of all data and reports must be submitted
3.3.2 Outdoor ambient temperature,
bythetestinggrouptotheownerorhisorherdesignatedagent.
3.3.3 Internal building temperature near storage system,
3.3.4 Collector loop flow rate and temperatures, and 4.5 Dataandreportsfromtheseproceduresandtestsmaybe
3.3.5 Storage temperature. used to compare the system performance over time, but should
3.3.6 Each system should be instrumented to the practical not be used to compare different systems or installations.
level required for calculation (see NIST standard 76-1137 for
4.6 Testisforanewlyinstalledsystemandalsoforperiodic
another method to instrument and evaluate solar systems).
checking.
Some sites may need additional instrumentation as a result of
their unique requirements. Fig. 1 shows a typical closed loop
5. Procedures
system with the instrumentation required for the various tests.
5.1 Preparation:
3.4 Thevarioustypesofavailableinstrumentationarelisted
5.1.1 Install and operate components and controls in accor-
in Tables 1-4.Approximate cost ranges, accuracy and applica-
dance with manufacturer’s instructions.
tion information are given. Most of the necessary instruments
arepresentlyusedinconventionalheatingandairconditioning 5.1.2 Usetemporaryportableinstrumentationoranyperma-
work except the pyranometer or solar radiation flux-measuring nent instruments installed for continuous monitoring to evalu-
instruments. ate system performance as long as accuracy is 62% of full
FIG. 1 Closed Loop System—One Tank
E1160−13 (2021)
TABLE 1 Solar Radiation Probes
Approximate
Type of Sensor Accuracy Type of Output Special Comments
Cost (dollars)
Pyranometer 150 to 1000 1–3 % of instantaneous Analog electrical millivolt Mounting point must be
value output, may need amplifier unshaded; some models
increase error increase error
by tilting
Integrating pyranometer 150 to 1000 5 % of integrated value Mechanical totalizer (and Some models provide
analog electrical on some instantaneous reading
models)
Photovoltaic solar cell 25 to 150 ±5 % of instantaneous Analog Drift or degradation over
value long periods
TABLE 2 Thermal Sensors
Approximate
Type of Sensor Accuracy Convenience Type of Output Special Comments
Cost (dollars)
Bi-metallic 25 to 50 High; 1 % or less of Good, when installed correctly Visual Not reliable for differential temperatures,
thermometer full scale time lag present; clip on type available
Bulb type 25 High Difficult to read because of Visual Very fragile
thermometer small scale
Digital thermometer 100 + Depends on type of Excellent, one indicator can Visual (digital) Probes typically cost $50
probe(s), typically serve several locations (probes)
0.5°C (1°F)
Thermocouple 25 to 30 Fair, 1°C (2°F) Excellent when coupled with Analog (electrical) Not reliable for measuring temperature
indicator differences; requires special wire for
installation
Resistance 60 High 0.25°C (0.5°F) or Excellent when coupled with Analog (electrical) Especially suited for measuring
temperature better indicator temperature differences
detectors (HTD)
Thermistors 1 to 30 Good, 0.5°C (1°F) Excellent when coupled with Analog (electrical) Not available in proper housing; can be
indicator damaged
Tapes 2 to 3 Fair, 1–3°C (2–5°F) Excellent, reusable Visual Inexpensive
steps
TABLE 3 Liquid Flow Sensors and Indicators
Approximate
Type of Sensor Accuracy Convenience Type of Output
Cost (dollars)
Pressure gages 50 Strictly a flow indicator Low Visual
Float type 30 Fair, + 5 % full scale accuracy Moderate Visual
TABLE 4 Air Flowmeters
Approximate
Type of Sensor Accuracy Type of Output Special Comments
A
Cost (dollars)
Hot wire anemometer 600 to 1000 Moderate, 2 % of full scale; Analog (electrical) Some models easily damaged by debris and improper
recalibration necessary handling; must be properly located in order to determine
mean flow
Turbine 300 Good, 1 % of flow Analog (electrical) Must be properly located in order to determine mean flow
Pitot tube 300 Fair, 1 to 5 % Visual or analog (electrical) Standard for measuring duct velocities
A
Includes readout device or transmitter.
scale and reproducibility is ≥5% and instrumentation is subsystems. The manual containing drawings, specifications,
installed properly in accordance with manufacturer’s instruc- and engineering data shall serve as a benchmark for the
tion. inspection.
5.1.3 Operate the system in a normal and satisfactory
5.2.2 The following components should be inspected for
manner for several days before the on-site performance test. properinstallation(seePracticeE1056)andoperationtocheck
Operate the entire system at a nearly steady-state condition for
for any malfunctions, leaks or improper adjustments. See Ref
at least a 2-h period before testing. Conduct tests for collector (1) for an Installation Checklist.
effectiveness under clear, sunny conditions.
5.2.2.1 Collectors and connections,
5.2.2.2 Controls and sensors,
5.2 General Inspection:
5.2.2.3 Insulation,
5.2.1 The ability to perform as intended for the specified
5.2.2.4 Interconnections—mechanical and electrical,
periodoftimedefinessystemdurabilityandreliability.System
performance depends on the proper operation of each of the 5.2.2.5 Pumps and motors,
E1160−13 (2021)
5.2.2.6 Valves and fittings, installed. The return temperature should also show a gradual
5.2.2.7 Storage containers and media, increase during daylight hours (will fluctuate depending on
5.2.2.8 Heat exchangers, water usage).
5.2.2.9 Dampers and ducting,
6.2 Interpretation and Report of Results—If temperature
5.2.2.10 Air or liquid systems leaks,
rise is unreasonable (too little or too much—see 6.1) check
5.2.2.11 Interrelated support systems, including other air
pump or blower for proper operation and fluid level in system.
handlers, chillers, heaters, or heat pumps, and
5.2.2.12 Fans and air handlers.
7. Test Level B—Estimation of Flow Rates
5.2.3 Mostofthefailuresreportedhavebeeninthecollector
7.1 Procedures:
subsystem and connections and controls with considerably
7.1.1 In indirect system, record total head (discharge
fewerfailuresreportedforvalvesandpumpsubsystems.There
pressure-suction pressure), and establish flow rate using inter-
has been a high incidence of improper system operation due to
section of system curve with blower curve provided by
controls improperly connected or adjusted.
manufacturer(seeFig.2correctforantifreezepercentage).See
5.2.4 Avisual inspection should be made of all connections
Ref (2) for more information.
(see Practice E1056, 6.7.6) to check for evidence of leaks or
7.1.2 In-direct or open system measure discharge pressure
potential future corrosion due to improper use of materials
with drain valve and makeup valve closed.Then open makeup
(Practice E1056, 6.7.2), improper joining of dissimilar metals
valve, turn on pump and adjust the drain valve until the
(Practice E1056, 6.7.14), or improper fluids (Practice E1056,
pressureisthesameasin7.1.1(seeFig.3foroperatingpoint).
6.5). See Ref (2) for a leak check on air systems. A pressure
7.2 Instrumentation—Apressure gage (see Fig. 4 and Table
check on liquid systems should be done to see if it meets
3), a stopwatch, and a container may be needed for this test.
...