Carrier Idrofan 42NH, Installation, Operating And Maintenance Instruction

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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).
■ Refit the valve actuators taking care to ensure that
they are correctly fixed to the valve body.
■ Reconnect the flexible water pipes by tightening the
union nuts. Retighten all the water connections and
ensure that all gaskets have been changed and
correctly fitted (maximum torque 15 N·m).
■ Open the isolating valves on the manifolds and purge
all air from the system.
■ Check that there are no leaks and reconnect the
power to the unit.
WARNING: When replacing a valve always ensure
that the direction of flow through the valve is as
shown by the arrow on the valve body. If the
direction of flow is wrong, the valve body will
deteriorate rapidly and the flow control will be
distorted.
4.9 - Flexible pipe option
Minimum bending radius:
■ Non-insulated pipes 72 mm
■ Insulated pipes 106 mm.
Connections for unit size 2, 3, 4 and 5: 1/2’’ diameter
(female)
Connections for unit size 6 and 7: 3/4’’ diameter (female)
4 - COMPONENTS AND MAINTENANCE
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