DESCRIPTION
The "Astra" model F and G Air Maintenance Devices are designed to provide direct filling of a Dry Pipe Sprinkler System to the required air pressure and also maintain, through a bypass arrangement, the correct air pressure in the system at all times. The system pressure desired may be obtained by adjusting the air pressure regulator. (Refer to the Dry Pipe Valve litterature forthe proper air pressure required.)
The model F is used when a sprinkler system air compressor is the air source. The air pressure switch is used to control the air compressor motor and is field adjustable to the desired system air pressure. The model G is normally used when the compressed air is supplied by the owner of the building.