Water Factory Systems SQC Helpful Information For Owner - page 6

How to Service the Storage Tank

The storage tank air precharge should be checked yearly. The tank should be disconnected

from the system and air added to the Shrader valve (like the one on a bicycle tire). The ball valve

on the top of the tank should be open. The air charge should be 7-8 psi (48-55 kPa). If the tank

will not hold an air charge, inspect the bladder. If the bladder is OK, replace the Shrader valve. If

the tank still will not hold an air charge, replace the tank.

How Much Water Should the Tank Hold?

The amount of water the storage tank will hold is determined by the air precharge and the

feedwater pressure. The RO system will fill the tank until the pressure in the tank reaches two-

thirds of the feedwater pressure. With an air precharge of 7-8 psi (48-55 kPa), the following chart

lists approximate storage capacities when the tank is full:

Feedwater Pressure

Tank Capacity

80 psi (552 kPa)

2.3 gallons (8.7 liters)

60 psi (414 kPa)

2.1 gallons (7.9 liters)

40 psi (276 kPa)

1.5 gallons (5.7 liters)

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