Water Flow Control Valves; Description; Replacing Actuators; Electrical Circuit Diagrams For Actuators - Carrier 42BJ ULTRA Series Installation Manual

8 - WATER FLOW CONTROL VALVES

These valves are two-port or three-port type, with a body desi-
gned to withstand a 16 bar operating pressure.
8.1 - Electrothermal actuator (on/off)
This on/off type actuator is used with a Carrier room thermo-
stat (electromechanical controller).
NOTE:
The electrothermal actuator is delivered in the normally clo-
sed position regardless of the two-port or three-port valve
body used (port A-AB closed in the case of a three-port
valve).
Therefore to enable the installation to be filled with water,
the water circuits to be equalised and the units to be purged,
the valves will have to be opened by sending a command
from the wall thermostats.

8.2 - Replacing actuators

The actuators on both the chilled water and the hot water
valves may be replaced if either develops a fault.
a) Disconnect the power supply to the unit before carrying
out any work on a unit.
b) Disconnect the actuator power supply cable.
Remove the plastic protection cover (held in place with two
hexagon head (8 mm AF) screws). Disconnect the quick
connect power supply cable on the actuator. This can be done
by using a screwdriver to press down on the spring tongue and
pulling out the wire from the appropriate terminal.
c) Uncouple the faulty actuator. Reverse the removal proce-
dure described above when installing the replacement
motor.
WARNING:
Ensure that the actuator is firmly screwed to the valve body
(maximum torque 15 N/m)

8.3 - Electrical circuit diagrams for actuators

BROWN
FM
BLUE
ACTUATOR FOR
HEATING VALVE
ACTUATOR FOR
COOLING VALVE
BROWN
BLACK
FM
CHANGEOVER

8.4 - Replacing a valve body

a) Disconnect the power supply to the unit before carrying
out any work on a unit.
b) Close the isolating valves on the manifolds.
c) Uncouple the actuator from the valve body.
d) Disconnect the 1/2" gas connection nut on the flexible
water pipe from the valve to be replaced.
e) Unscrew and remove the valve body to be replaced (1/2"
gas connection).
f) Install a new valve body on the coil.
g) Reconnect the flexible water pipe.
h) Reinstall the actuator ensuring that it is securely
screwed to the valve body.
i) Tighten all water pipes ensuring that all seals are cor-
rectly installed (torque 15 N/m).
j) Open the isolating valves on the manifolds and bleed all
air from the system.
k) Check that there are no leaks and restart the ULTRA.
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 will deteriorate
rapidly.
BLUE
RED BROWN
ACTUATOR FOR
COOLING VALVE
21