Watts Industries, Inc.
815 Chestnut St.
North Andover MA
01845-6098
INSTRUCTIONS FOR INSTALLING
SERIES 25AUB
WATER PRESSURE REDUCING VALVES
INSTALL VALVE IN THE LINE SUPPLY PRESSURE CONNECTED TO THE
"IN" CONNECTION.
These regulators can be installed horizontally in either an upright or inverted position
or in a vertical position, and must be installed in an accessible location to facilitate
servicing the regulator.
For household use install the reducing valve when possible, so that the sill cock line is on the high or street side of the reducing valve. Before installing the reducing valve, flush out the line to remove loose dirt and scale, which might damage valve disc and seat. On valves having strainers the screen should be removed and cleaned at least once every six months, more often if water conditions are bad.
TO READJUST Pressure, loosen check nut and turn adjusting screw clockwise to raise pressure and counter clockwise to lower pressure.
The use of a water pressure-reducing valve normally creates a closed system. When water is heated in a closed system, it expands, causing an increase in pressure. This pressure may increase to the set pressure of the relief valve (on the water heater) causing it to drip, thus releasing the expanding water and protecting the system against excessive pressure, This increase in the system pressure over that regulated by the reducing valve is called "thermal expansion pressure".
No. 25AUB by-pass Model water pressure reducing valves, are an economical solution of this annoyance, since under certain conditions it allows the expanding water to escape back into the supply main before it can affect the relief valve.
Effectiveness of the Thermal Expansion by-pass featureis limited to systems where the
street main pressure is less than the setting of the heater relief valve. Therefore, the
highest allowable pressure setting for the relief valve should be selected for widest
effectiveness of a Thermal Expansion by-pass
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Annual inspection of all water system safety and control valves is required and necessary. Regular inspection, testing and cleaning assures maximum life and proper product function.
How to determine Thermal Expansion
When high house pressure is evident, open a cold water faucet. If your pressure gauge shows immediate drop to the regulated reduced pressure setting it indicates the regulator is operating correctly end that thermal-expansion is the cause of the expanded pressure. For additional detailed information, send for folder F-RV.