Function
- Dual function: non-return valve and hydraulic alarm activation.
- Hydraulic retard chamber for time delay and false alarm prevention.
- Hydraulic alarm operates without electrical power supply.
- For constant and variable water pressure supplies.
Wet Alarm Check Valve
AG Model H Wet Alarm Check Valves
Model H-1, H-2 & H-3 — 300 psi (21 bar), ductile iron, 3" to 8" (80–200 mm)
AG Model H Wet Alarm Check Valves from AG Fire Sprinkler are ductile iron valves for wet pipe sprinkler systems, combining non-return and hydraulic alarm functions, rated 300 psi (21 bar) in sizes 3" to 8".
Manufactured by
AG Fire Sprinkler
AG Model H Wet Alarm Check Valves
Review the confirmed product information, including description, features, benefits, and applications.
The AG Model H-1, H-2 and H-3 Alarm Check Valves from AG Fire Sprinkler are used in wet pipe fire sprinkler systems. They serve two functions: they prevent reverse flow of water through the valve body (non-return), and they operate a hydraulic fire alarm that does not depend on an electrical power supply.
A hydraulic retard chamber provides a time delay to avoid false alarms caused by fluctuating water supply pressure. Where a constant pressure water supply is used, the retard chamber is not needed. Electrical pressure switches and other supplementary alarms can also be connected.
The valves are offered with flange/flange (H-1), groove/groove (H-2) or flange/groove (H-3) ends, in sizes 3" to 8", with loose, preassembled or fully assembled factory trim.
Pressure & Materials
- Water working pressure rating: 300 psi (21 bar).
- Factory tested hydrostatically at 450 psi (32 bar).
- Body and cover: ductile iron ASTM A536.
- Bronze seat ring with EPDM clapper facing.
Models & Sizes
- H-1: flange / flange.
- H-2: groove / groove.
- H-3: flange / groove.
- Sizes 3" (80 mm), 4" (100 mm), 6" (150 mm) and 8" (200 mm).
Installation & Trim
- 3", 4" and 6" valves: vertical or horizontal installation.
- 8" valves: vertical installation.
- Loose, preassembled or fully assembled factory trim.
- Relief trim available as an option.
Wet System Control
Provides non-return and alarm functions in one valve for wet sprinkler systems.
Fewer False Alarms
The retard chamber absorbs pressure variations that could trigger false alarms.
Simple Integration
Fits standard wet pipe system configurations with flanged or grooved ends.
No Power Needed
The alarm operates hydraulically, independent of electrical supply.
AG Model H alarm check valves are used in wet pipe sprinkler systems that need hydraulic alarm activation and non-return function.
Commercial Buildings
Wet sprinkler risers in offices, malls and hotels.
Industrial Facilities
Wet pipe systems in factories and warehouses.
Residential Buildings
Wet sprinkler systems in residential towers and housing.
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