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23
ENGLISH
4.8.1 - Optional balancing valves
Two-way valve with waterflow balancing function is
embedded with a differential pressure controller (with or
without pressure test points to control the waterflow
settings). The setting of the valve is shown in Fig. 16.
The manual control knob (16a) is ready fitted to protect
valve stem and pre-set mechanism and facilitates manual
control of valve during commissioning.
Setting procedure:
•
Remove control knob from the valve (16a)
•
Loosen knurled nut (16b).
•
Adjust the desired dial setting with the white knob
(16c) - see table below.
•
Retighten knurled nut by hand (16d).
Waterflow to adjust [l/h]
1/2’ valve
Not
Standard
3/4’ valve
Available
1’’ valve
Available Available
ON/OFF
actuator
Not
Standard Available Available
Moduling /
3p actua.
Not
Standard Available
Available
Waterflow range :
200l/h (*) 600l/h (*) 1200l/h (*) 1600l/h (*)
Dial Setting
Min
NA
NA
NA
NA
0.2
NA
NA
NA
NA
0.4
NA
NA
NA
NA
0.5
30
100
NA
NA
0.6
35
115
200
220
0.8
40
130
260
290
1
50
160
310
250
1.2
60
180
380
420
1.4
70
210
430
480
1.6
80
240
490
550
1.8
90
270
550
610
2
100
300
610
680
2.2
110
320
660
740
2.4
120
350
730
810
2.6
130
380
780
870
2.8
140
410
840
940
3
150
440
900
1000
3.2
160
460
960
1070
3.4
170
490
1010
1130
3.6
180
520
1070
1200
3.8
190
550
1130
1260
MAX
200
575
1190
1330
(*) : Maximum specified water flow on the valve body
WARNING: The valves have to be open when flushing or
pressure testing the system. Strong pressure impacts can
damage closed valves.
Differential pressure across the valve’s control path is not
allowed to exceed 400 kPa.
4.8.2 - 230 V - Actuators
Two types of valve actuators are provided : electrothermal
actuator (on/off control) or modulating actuator (3-point).
The actuator supply is 230 V a.c.
4.8.3. 24 V - Actuators
Three types of valve actuators are provided : one
electrothermal actuator (on/off control) or two modulating
actuators (3-point or 0-10V).
Both modulating actuators can be operated manually with
a hexagonal key. The 0-10V command voltage range of the
modulating actuator can also be adjusted.
The actuator supply is 24 V a.c.
NOTE: 24V actuators are not compatible with Carrier
controllers (Thermostats A/B/C/D, WTC & NTC).
4.8.4 - Actuator replacement procedure
The actuators on both the chilled water and the hot water
valves may be replaced in case of failure.
WARNING : Do not connect on the same neutral wire the
valve actuator 24 Vac and the controller.
•
Disconnect the power supply to the unit before carrying
out any work on a unit.
•
Disconnect the actuator power supply cable.
-
230 V type actuator used with the Carrier numeric
controller: Disconnect the actuator power supply
cable fitted with a quick connector.
-
230 V actuator used with an electronic thermostat:
Remove the plastic protection cover held in place
with two screws. Disconnect the actuator power
supply cable connected to the quick connector.
This can be done by pressing down the spring
tongue using a screwdriver and pulling out the
wire from the appropriate terminal.
•
Uncouple the faulty actuator. Refitting is by the
reversal of the procedure described above.
WARNING: Ensure that the actuator is firmly screwed to
the valve body (maximum torque 15 N·m).
4.8.5 - Valve body replacement procedure
•
Disconnect the power supply before carrying out any
work on a unit.
•
Close the isolating valves on the manifolds.
•
Unscrew the union nuts to disconnect the flexible
water pipes.
•
Remove the valve actuators taking care to identify
the cooling and heating valves.
•
Disconnect the flexible condensate drain pipe which
is held in place by a collar (the collar is not supplied
by Carrier).Remove the two-way or four-way water
flow control valve bodies. Depending how the unit is
configured, the four-way valve coupling may be fitted
with a heating/cooling changeover switch, if so do not
remove it.
•
Fit the new valve body to the coil (fit new gaskets).
•
Reconnect the flexible condensate drain pipe which
is held in place by a collar (the collar is not supplied
by Carrier).
Summary of Contents for 42NH series
Page 7: ...7 9a 10 10b 10a 13 13a 13a 9b 11 11a 11a 12 12b 12a ...
Page 8: ...8 5 1 2 1 2 1 2 3 4 2w v 9 2 6 5 7 8 6 4w v 5 2w v B 5 10 2 6 14 ...
Page 9: ...9 16a 16b 16d 16e 16c 15a 15b 15c 15d 15e 15 17a 17b 17c 17 16 16a 16b 16c 16d ...
Page 10: ...10 1 3 5 2 4 5a 5b 18 4a 4b ...
Page 11: ...11 19 19a ...