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THREADED CONNECTIONS:
CBV-NPT5 models are tapped with NPT threaded connections.
All threaded connections should be sealed using an approved
pipe sealant per industry standards. Once the CBV installation
has been completed and the system has been filled and purged,
each valve loop must be adjusted to the correct flow setting.
Employ piping best practice when engaging pipe to threaded
valves. Overtightening when installing valves may result in
fracturing of the valve body at the threads.
Warning:
Aurora DOES NOT recommend leak testing an HVAC
system with air due to safety concerns.
Testing HVAC systems with pressurized air can
be dangerous due to the high compressibility of air, as
compared to water.
OPERATION:
Valves are circuit balancing valves that are selected to deliver
the correct flow in a piping circuit based on line size and design
flow rate.
To set the system flow, adjust the handwheel position until the
differential pressure reading across the venturi corresponds to
the required GPM.
The valve operates from fully open to closed by a clockwise
rotation of the red handwheel using five 360° turns. Two
indicators describe the position of the valve: the handwheel
turns dial and the micrometer scale.
• "Handwheel Turns" Dial:
This dial is printed on the outer surface of a gearing
mechanism located inside the lower half of the handle
assembly (Fig. 6). Each complete 360° revolution of the
handwheel is visible through a display window and is scaled
0 – 5 to indicate the valve position in terms of the number of
full turns. (Fig. 3)
• Micrometer Scale:
This scale is marked 0 – 9 and is located on the upper half
of the handle assembly. Each mark represents 1/10th of a
full, 360° turn of opening when lined up with an arrow-
head symbol, located above the handwheel turns display
window. (Fig. 3)
Fig. 3: CBV setting of 0.0 indicates that the valve is closed. Both the
handwheel turns dial and the micrometer scale indicate a
valve position reading of 0.
MODELS CBV-S5 AND CBV-NPT5
The valve is considered "zeroed" when fully closed hand-tight.
The "0" on the micrometer scale should be within one half of
1/10th of a turn of the arrowhead symbol when the valve is
closed hand-tight. DO NOT USE A WRENCH ON THESE
VALVES – THEY SHOULD BE OPENED AND CLOSED
HAND-TIGHT ONLY!
Fig. 4: CBV setting of 2.3 indicates that the valve is partially open
Fig. 5: CBV setting of 5.0 indicates that the valve is fully opened. In
Micrometer scale
"Handwheel
turns" dial
3
(2.3 turns open).
some cases, the valve may open as much as 5.3 turns, due to
the depth of the stem threads. This is not a problem with the
valve; however, the performance curves for these CBVs are
calibrated only to 5.0 turns.
CAUTION
Hot water leakage can occur from metering ports
(P.M.P.'s) during probe insertion and hookup of metering
device. Wear protective eyewear and clothing to prevent
personal injury when measuring pressure.
ITEM 1040 SERIES
DATED MARCH 2015
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