Brochure

The performance specifications are nominal and conform to acceptable industry standards. For applications at conditions beyond these specifications, consult the local Johnson Controls office.
Johnson Controls, Inc. shall not be liable for damages resulting from misapplication or misuse of its products. © 2015 Johnson Controls, Inc. www.johnsoncontrols.com
R-168
V148 Series Three-Way Pressure-Actuated Water-Regulating Valves
(Continued)
Valves and Valve Accessories
Use these equations to convert between U.S. and S.I. units.
•1 dm
3
/s = 3.6 m
3
/h = 15.9 U.S. gal. /min. = 13.2 U.K. gal. /min.
• 1 bar = 100 kPa = 0.1 MPa  1.02 kg/cm
2
= 0.987 atm  14.5 psi
c. From the Pressure-Temperature Chart for the refrigerant
selected, read the Refrigerant Condensing Pressure (P
COND
)
(operating head pressure) corresponding to the selected
condensing temperature.
d. Subtract the Valve Opening Pressure from the Refrigerant
Condensing Pressure. This gives the head pressure rise.
3. Determine the available water pressure to the valve (P
AVAIL
) using
the following steps. This is the actual water pressure available to
force water through the valve.
a. Determine the minimum inlet pressure (P
IN
). This is the water
pressure from city water mains, pumps, or other sources.
b. Pressure drop through condenser (
P
COND
) is the difference in
water pressure between the condenser inlet and the condenser
outlet. Obtain this information from the condenser manufacturer.
c. Estimate or calculate the pressure drop through all associated
piping (P
LOSS
).
d. Subtract the P
COND
and P
LOSS
from P
IN
. The result is P
AVAIL
.
4. Select the proper valve size from the flowcharts by locating a point
on a chart that satisfies the flow, the head pressure rise above
opening point, and the pressure drop across the valve.
Valve Opening Pressure, EK and AL Models (Top) or
GK1 and GL1 Models (Bottom)
FIG:V14x_eqn_opn_prssr
P = P +7 psi (0.5 bar)
OPEN CLOSE
P = P +10 psi (0.7 bar)
OPEN CLOSE
Refrigerant Head Pressure Rise
FIG
:eqn_hd_prssr_rs
P = P - P
RISE COND OPEN
Available Water Pressure
Cooling Tower
Pump
P
1
P
2
P
P
Loss 1
Loss 2
3-Way
Valve
P
IN
COND
P
P
1
P
2
=
-
LOSS
P
P
P
Loss 1
Loss 2
=
+
+ ...
Condenser
Balancing Valve
Bypass Line
FIG:3wy_prss_d
rp
P= P- (P + P)
AVAIL IN COND LOSS

3/4 in. V148EK Valve
30
25
20
15
10
5
0
10 15 20 25 30 35
40 45 50 55 60
30
20
15
10
7
Flow
(gpm)
Refrigerant Head Pressure Rise (psi)
Pressure Drop Through Valve (psi)
FIG:V148EK_chrt
1 in. V148AL Valve
55
50
45
40
35
30
25
20
15
10
5
10 15
20
25 30 35 40 45 50 55 60
10
7
Flow
(gpm)
Refrigerant Head Pressure Rise (psi)
15
30
20
0
Pressure Drop Through Valve (psi)
FIG:V148AL_chrt