Water Valve Piping Arrangement
It is important to follow the proper piping arrangement for
both two-way and three-way water valves. Incorrect pip-
ing arrangements will damage the unit. The field piping
schematic is illustrated in Figure I8.
For Two-way Valve
Two-way valves should be installed in accordance to the
arrow direction marked on the valve body for the water
inlet or supply line. Two-way valves should be installed
with the disc upstream. If installed with disc downstream,
flow curve will be deeper. If installed “backwards” it is not
necessary to remove and change. No damage or control
problems will occur.
For Three-way Valve
Three-way valves must be installed with the ‘AB’ marked
or common port to the supply water line, the ‘A’ marked
or control port to the coil and the ‘B’ marked, ‘Bypass’ or
middle port to the return water line.
Correct Piping
Incorrect Piping
Valve and Actuator Installation
Mount the valve directly in the pipe where the assem-
bly will not block the system vent or other components.
Do not grip the actuator while making and tightening up
plumbing connections. Either hold valve body in your
hand or attach adjustable wrench across the hexagonal
or flat faces on the valve body. If assembling valve train on
bench, take care not to deform the body with a vise.
1 input, 2 outputs
Coil
Return
Supply
B
A
AB
Figure I11: Correct three-way diverting valve piping
1 input, 2 outputs
Coil
Return
Supply
B
A
AB
Figure I12: Incorrect three-way diverting valve piping
Refrigerant components
P
P
P
Access valve
Access valves
Scroll compressor
Switch high
pressure
Crank case heater
Switch low optional
pressure valve kit
Pressure
transducer
Pressure transducer factory
mounted at compressor
discharge port
Unit water inlet
Field mounted
Head pressure
control valve
option
On/off valve
accessory
Strainer
Modulating
three-way valve
Motorized valve
water shut-off
Water inlet
H
B
Flow
switch
option
Water inlet
Unit water outlet
A
T
C
B
J
K
Figure I8: Water valve piping arrangement
AB
A
A
AB
A AB 0%
AB 100%
Two-way valves
should be installed
with the disc
upstream.
Flow direction
A
AB
Belimo
A
Figure I9: Two-way valve arrangement
Diverting
A
AB
B
A
AB
B
A
B
A
B
AB 100%
AB 0%
AB 70%
AB 0%
The A-port must
be piped to the coil
to maintain proper
control.
Figure I10: Three-way valve arrangement
CAUTION
If the valve is piped incorrectly, it must be re-piped as it
may restrict flow and cause damage to the unit.
Figure I13: Valve installation
VCES-VHC-IOM-1F – VHC-36, -42 & -50
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