Low Lead Type NL300L and NL310WJ Air Volume Controls0 pages

SAG - 18

Product Data
SPECIAL APPLICATION GAUGES

Low Lead Type NL300L and NL310WJ
Air Volume Controls
DESCRIPTION

SPECIFICATIONS NL310WJ

U.S. Gauge low lead air volume controls adhere to the
“Reduction of Lead in Drinking Water Act” enacted by
the U.S. Congress January 2011.

HOUSING: Die cast zinc, with 1-1/4 – 11-1/2 ANPT male
connection for tank installation, and 1/4-18 ANPT female
connection to accept a U.S. Gauge Model P-500 pressure
gauge, 1/4-18 ANPT, LM connection

t U.S. Gauge low lead air volume controls are designed
for potable domestic water supply systems which deliver a quantity of air to the pressure tank with each cycle
of pump operation. Insufficient air in the pressure tank
causes frequent operation of the pump. Too much air in
the pressure tank will permit large bubbles to be carried
into the piping system. This causes a disagreeable noise
and sputtering at the faucets.
t It is the function of U.S. Gauge air volume controls to
maintain the correct relationship between the volume of
air and the quantity of water in the pressure tank.

SPECIFICATIONS NL300L
HOUSING: Die cast zinc, with 1-1/4 – 11-1/2 ANPT male
connection for tank installation, and 1/4-18 ANPT female
connection to accept a U.S. Gauge Model P-500 pressure
gauge, 1/4-18 ANPT, LM connection

MAIN VALVE: Brass stem with a neoprene seat, float actuated
RELIEF VALVE: Brass, spring loaded pressure actuatedt
Manually adjustable between 15 and 40 psi. Stock units preset
at 25 psi
FLOAT: Plastic bulb, mounted on a solid, low lead brass rod
DEEP WELL OPERATION - Type NL310WJ
When there is an excess of air and the water level is low, the float opens
the main valve of the control, permitting air to be vented to a chamber
within the control. This chamber contains an adjustable pressure relief
valve which exhausts the excess air to the atmosphere, providing the
pressure in the tank is higher than the relief valve setting. As the float
rises with the increase in water level the main valve closes, trapping the
remaining volume of air in the tank. The optimum relationship between
the volume of air and water in the tank is thus maintained.

AIR INLET VALVE: Schrader or Dill type valve is mounted in the
hose connection
FLOAT: Plastic bulb, mounted on a solid, low lead brass rod
INTERNALS: A flexible, molded neoprene plug of unique design
acts as both dividing wall and fulcrum through which float
action is transmitted to the air inlet valve
SHALLOW WELL OPERATION - Type NL300L
When the water level is high, the float, secured to a float rod extending
through a flexible dividing wall, opens an air inlet valve in the body of the
control. The air inlet valve is connected through 48" long polyethylene
tubing to a snifter valve on the pump and has no direct connection into
the tank. The snifter valve admits air into the pump but prevents the
water in the pump from escaping back through it. Air is drawn into the
pump through the air inlet valve, connecting tubing and snifter valve and
carried out with the water into the tank. This operation continues until
the volume of air increases to the proper amount, at which time the float
closes the air inlet valve, shutting off the supply of air to the pump. The
optimum relationship between the volume of air and water in the tank is
thus maintained.

Model
NL300L

Model
NL310WJ

Spec Number Selection Chart
Model Number

Spec No.

Type NL300L

148542ANL

Type NL310WJ

148540ANL

Type NL310WJ spares - valve assembly

085043ANL

Type NL310WJ spares - valve seats

(shown with 162988NL,
Low Lead Model P-500
pressure gauge – sold
separately)

085392ANL

On-line order fax: +1 215-323-9450 or e-mail: usg.sales@ametek.com

Sales/Technical Support: +1 215-293-4100 | 205 Keith Valley Road | Horsham PA 19044 U.S.A.
© 2013, by AMETEK, Inc. All rights reserved.tt
Printed in the U.S.A.tt
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Specifications are subject to change without notice. Visit our Web site for the most up-to-date information.

www.ametekusg.com