S-12 - Valves.

S-12.1   General.

Valves shall be rated for the operating temperature and pressures of the solar thermal system and shall be compatible with the type of heat transfer medium and piping materials. Valves shall be installed in accordance with this Section.

(Ord. 2016-0055 § 20, 2016: Ord. 2013-0050 § 22, 2013.)

S-12.2   Heat Exchanger.

Isolation valves shall be installed on the supply and return side of the heat exchanger.

(Ord. 2016-0055 § 20, 2016.)

S-12.3   Pressure Vessels.

Isolation valves shall be installed on connections to pressure vessels.

(Ord. 2016-0055 § 20, 2016.)

S-12.4   Pressure Reducing Valves.

Isolation valves shall be installed on both sides of a pressure reducing valve.

(Ord. 2016-0055 § 20, 2016.)

S-12.5   Equipment, Components, and Appliances.

Serviceable equipment, components, and appliances within the system shall have isolation valves installed upstream and downstream of such devices.

(Ord. 2016-0055 § 20, 2016.)

S-12.6   Expansion Tanks.

Isolation valves shall be installed at connections to non-diaphragm-type expansions tanks.

(Ord. 2016-0055 § 20, 2016.)

S-12.7   Flow Balancing Valves.

Where flow balancing valves are installed, such valves shall be capable of increasing or decreasing the amount of flow by means of adjustment.

(Ord. 2016-0055 § 20, 2016.)

S-12.7.1   Location.

Balancing valves shall be installed at the outlet of each group of collectors.

(Ord. 2016-0055 § 20, 2016.)

S-12.8   Control Valves.

An approved three-way valve shall be permitted to be installed for manual control systems. An approved electric control valve shall be permitted to be installed for automatic control systems. The installation and operation of automatic control valves shall comply with the manufacturer's instructions.

(Ord. 2016-0055 § 20, 2016.)

S-12.8.1   Mixing or Temperature Control Valves.

Where mixing or temperature control valves are installed, such valves shall be capable of obtaining the design water temperature and design flow requirements.

(Ord. 2016-0055 § 20, 2016.)

S-12.9   Thermosiphoning.

An approved type check valve shall be installed on liquid heat transfer piping to control thermosiphoning of heated liquids.

(Ord. 2016-0055 § 20, 2016.)

S-12.10   Air Removal Device or Air Vents.

Isolation valves shall be installed where air removal devices or automatic air vents are utilized to permit cleaning, inspection, or repair without shutting the system down.

(Ord. 2016-0055 § 20, 2016.)

S-12.11   Closed Loop Systems.

Closed loop systems, where hose bibbs or similar valves are used to charge or drain the system, shall be of loose key type, have valve outlets capped, or have handles removed where the system is operational.

(Ord. 2016-0055 § 20, 2016.)

S-12.12   Fullway Valves.

A fullway valve shall be installed in the following locations:

(1)

On the water supply to a solar thermal system;

(2)

On the water supply pipe to a gravity or pressurized water tank; and

(3)

On the water supply pipe to a water heater.

(Ord. 2016-0055 § 20, 2016.)

S-12.13   Accessible.

Required fullway or shutoff valves shall be accessible.

(Ord. 2016-0055 § 20, 2016.)