Water Flow Switch
Flow Switch Dimensions
Flow Switch Installation
The flow switch must be externally field mounted in the
leaving or outlet water line. Before installation, the flow
switch vane must be trimmed for the size of piping being
used. A full size, trimmable stainless steel vane is pro-
vided with a removable laminate template. This template
is calibrated for brass or ductile iron reducing tee and
forged steel straight tee/brushing combination which al-
lows for field installation in pipeline from ½” to 2” diameter.
See Table I18 for approximate actuation and deactivation
values.
1. Carefully unpack the flow switch and remove any
packing material from the lower housing. Trim the
vane at the appropriate mark for the size of piping
being used.
2. Apply thread tape or sealant to the ½” male NPT
mounting threads and install the flow switch in the
system piping with the arrow on the side pointing in
the direction of flow.
3. The flow switch must be field wired to the standard
field wiring terminal strip as per wiring schematic for
24 VAC.
4. Avoid exceeding any of the maximum electrical rat-
ings which can lead to failure.
5. After installation, set the switch action to normally
open or normally closed. To change the switching
from normally open to normally closed, loosen, but do
not remove the two screws on the top cap. Slide the
reed switch assembly to expose the switch action se-
lected. Tighten screws when adjustment is complete.
1
1
2
2
3
3
4
4
5
5
One screw attaches
actuator to valve
Four actuator mounting
positions
Two-way flow pattern
Three-way flow pattern
(mixing shown)
Top of valve stem indicates
direction of flow
(Flow A to AB shown)
Note:
For diverting flow, flow
enters in AB and diverts
to A and B ports.
CCW
CCW
4 x 90°
A
A
AB
AB
B
A-AB
= 100%
A-AB =
100%
B-AB
= 0%
Figure I14: Valve and actuator assembly and
installation
Figure I15: Valve and actuator assembly and
installation
2¼” [57 mm]
1” [25 mm]
¼ (6) travel to normally
closed position
(2) 22 AWG Leadwires
18 (460) long
1/8 NPT – switch shown
in normally open position
Lower body
7/8 hex
½ NPTM
Vane
2-7/16” [62 mm]
2-7/8” [73 mm]
WARNING
Mechanical shock or vibration can cause permanent
damage to the switch. Avoid dropping the unit on hard
surfaces.
Table I18: Flow Switch Performance Data
Cold Water Flow Rates –
Approximate Actuation/Deactuation
Pipe
Trim
NO
NC
½”
L
2.6/2.3
2.6/2.5
9.8/8.7
9.8/9.5
¾”
J
3.1/2.7
3.1/2.8
11.7/10.2
11.7/10.6
1”
H
4.8/4.5
4.8/4.4
18.2/17.0
18.2/16.7
1¼”
E
6.2/5.6
6.1/5.6
23.5/21.2
23.1/21.2
1½”
C
8.2/7.7
8.2/7.7
31.0/29.1
31.0/29.1
2”
Full
9.5/9.1
9.5/9.0
36.0/34.4
36.0/34.1
GPM upper, LPM lower
VCES-VHC-IOM-1F – VHC-36, -42 & -50
56
