Closed loop or other type pressure systems shall be tested at one and one- half (1-1/2) times maximum designed operating pressure. (Section 316.2.3 of the Solar Energy Code) Manual air release vents shall be installed at all high points of the solar system as required by the system design requirements and installation instructions. (Automatic air release vents not recommended for glycol systems) Section 409.0 of the Solar Code Pressure relief valves at150 psi or needs to be equal to the expansion tank rating (Section 405.1.1b of the Solar Code) Double wall heat exchanger required (94.506.4.2 or Section 405.1 of the Solar Code) Expansion tank must be sized properly (Section 602 of the Solar Code) Temperature sensor Pump Air separator (optional) Charging Station (glycol) NO makeup water Drainback: Collectors must be rated for empty exposure (evacuated tube collector for example) Collectors must be sloped to drain Piping must be sloped to drain: ¼” per foot on exterior piping No air traps allowed in piping Vacuum relief valves shall be installed at the high point of the solar system for drain down or drain back system as required by the system design requirements and installation instructions. (Section 410 of the Solar Code) Piping and system components must be rated to take occasional high temp steam exposure No expansion tank necessary if system has an air gap Pump must be below drainback tank level Integral Collector Storage (ICS) or Batch Heater: Enclosed storage tank that acts as a collector. Cold water is supplied at the bottom of the tank (open loop). Generally used in single family dwellings. Storage Tanks: With heat exchangers must be double wall vented to atmosphere (look for discharge vent) Tankless type heaters used in conjunction with solar system must be approved for use Heat Exchangers: UL or other approved testing agency listing (Section 301 of the Solar Code) Double wall and vented to atmosphere (94.603.4.4 or Section 405.1 of the Solar Code) Tanks with coils (double wall) Drainback systems using non-potable heat transfer fluids Expansion Tanks: For all closed loop systems Properly sized Separate expansion tank for Glycol systems Most closed Loop glycol systems using Pressure Stagnation Prevention method
Closed loop or other type pressure systems shall be tested at one and one- half (1-1/2) times maximum designed operating pressure. (Section 316.2.3 of the Solar Energy Code) Manual air release vents shall be installed at all high points of the solar system as required by the system design requirements and installation instructions. (Automatic air release vents not recommended for glycol systems) Section 409.0 of the Solar Code Pressure relief valves at150 psi or needs to be equal to the expansion tank rating (Section 405.1.1b of the Solar Code) Double wall heat exchanger required (94.506.4.2 or Section 405.1 of the Solar Code) Expansion tank must be sized properly (Section 602 of the Solar Code) Temperature sensor Pump Air separator (optional) Charging Station (glycol) NO makeup water Drainback: Collectors must be rated for empty exposure (evacuated tube collector for example) Collectors must be sloped to drain Piping must be sloped to drain: ¼” per foot on exterior piping No air traps allowed in piping Vacuum relief valves shall be installed at the high point of the solar system for drain down or drain back system as required by the system design requirements and installation instructions. (Section 410 of the Solar Code) Piping and system components must be rated to take occasional high temp steam exposure No expansion tank necessary if system has an air gap Pump must be below drainback tank level Integral Collector Storage (ICS) or Batch Heater: Enclosed storage tank that acts as a collector. Cold water is supplied at the bottom of the tank (open loop). Generally used in single family dwellings. Storage Tanks: With heat exchangers must be double wall vented to atmosphere (look for discharge vent) Tankless type heaters used in conjunction with solar system must be approved for use Heat Exchangers: UL or other approved testing agency listing (Section 301 of the Solar Code) Double wall and vented to atmosphere (94.603.4.4 or Section 405.1 of the Solar Code) Tanks with coils (double wall) Drainback systems using non-potable heat transfer fluids Expansion Tanks: For all closed loop systems Properly sized Separate expansion tank for Glycol systems Most closed Loop glycol systems using Pressure Stagnation Prevention method
Solar-Water-heating-requirements-Los-Angeles.docx