988-00
Model 988 F4"r, Automatic air release and vacuum valve, Infinitely variable surge protection, stainless steel 316Ti

Features:

Automatic and infinitely variable air valve for potable water and waste water applications.
Recommended for outdoor application.
Maximum Operating Pressure: 250 psi (17.2 bar).
Operating Range: 0 – 250 psi (0 - 17.2 bar).
Patented valve seat does not contact the medium (air cushion).

Infinitely variable surge protection

In general understanding the surge protection of an ARV is a measure taken to protect the pipeline system. Filling of the pipeline should be within international standards to prevent water hammer (5ft/s) or (0.25m/s) and correct opening and closing of valves is fundamental. The design of the H-TEC F4”r ARV allows for large volumes of air (in/out). The unique function for infinite air release/intake, due to the automatic movements of the diaphragm in operation modus, (e.g. fluid level rises, diameter of orifice is reducing infinitely variable) soft sealing and slowing the water column preventing water hammer.
Traditional ARV`s operate with two functions: open or closed. The rubber diaphragm of the H-TEC model 988 F4”r is infinitely variable operating. In case of increased velocity in the valve the float will lift slow and throttle down the air flow. This function slows the water column, water hammer from this ARV will not occur. The H-TEC 988 F4”r ARV has an integrated pressure spring on the vertical shaft attached to the float. This mechanical feature protects from vibrations, smooth function, prevents amplified movements.
No additional surge prevention unit necessary.

Capacities:

Maximum air release capacity: 2,500 cfm

Vacuum flow rate at negative pressure of 12 psi (0.8 bar): 3,000 cfm (5,100 m3/h)