46
System Pre-Start Procedures (Continued)
Table 4-1
“Temperature vs Resistance” Curve for EVP & VAV sensors
3000
3200
3400
3600
3800
4000
4200
20 40 60 80 100 120 140 160 180 200 220
Temperature -
O
F (
O
C)
Resistance (Ohms
(-6.7
o
C) (4.4
o
C) (15.6
o
C) (26.7
o
C) (37.8
o
C) (48.9
o
C) (60.0
o
C) (71.1
o
C) (82.2
o
C) (93.3
o
C) (104.4
o
C)
3483 ± 10 Ohms @
77
O
F (25
O
C)
Economizer Actuator Checkout
Used with “Zone” or “Discharge Air” Temperature
Controller
The following procedures should be used to verify that the
field provided economizer actuator(s) function properly.
These procedures are based on using a typical Honeywell
actuator. If another type actuator is used, refer to the spe-
cific checkout procedures for that actuator.
1. Turn all control switches to the “Off” position to deactivate
the Evaporator Fan and the Mechanical Cooling. Verify
that the main power disconnect switch for the condens-
ing unit and the control circuit switch 1S2, in the unit con-
trol panel, is “OFF”.
2. Verify that the field provided disconnect switch and/or the
control circuit switch for the economizer actuator(s) is
“OFF”.
3. At the actuator, disconnect the control wires connected to
Terminals W, R, B, and Y.
4. Install a jumper across the actuator terminals
R-to-W-to-B.
5. Close the field provided disconnect switch and/or the
control circuit switch for the economizer actuator(s). If
the economizer actuator is working properly, it should
drive to mid-position.
HAZARDOUS VOLTAGE
ROTATING PARTS!
UNIT STARTS AUTOMATICALLY
Make sure all personnel are standing clear of the unit
before proceeding. The system components will start
when the power is applied.
6. Open the field provided disconnect switch and/or the
control circuit switch for the economizer actuator(s) and
remove the jumpers installed in step 4.
7. Reconnect the control wires to the actuator terminals W,
R, B, and Y.
8. Restore power to the actuator circuit and turn all control
switches to the “ON” position and restore power to the
system.
EVP Chiller Control Checkout
(Honeywell W7100G)
Note: The following checkout procedure must be
performed in its entirety and in the sequence given.
The W7100G (6U11) chilled water controller can be
checked out using a highly accurate digital volt-ohmmeter,
the W7100 accessory tool kit (Trane part # TOL-0101 or
Honeywell part # 4074EDJ), and the Honeywell 4074EFV
resistor bag assembly.
1. Verify that the main power disconnect switch and the
control circuit switch 1S2, in the unit control panel, is
“OFF”.
2. At the unit control panel, unplug the reset relay 1K11 and
1K12, (1K12 used on 40 through 60 Ton units only). Re-
fer to the connection diagram that shipped with the unit
for the location of the relay(s).
3. At the Chilled Water controller (6U11) inside the remote
panel, disconnect the sensor (6RT2) leads form Termi-
nals T & T1.
4. Remove the 3,400 ohm resistor (blue leads) from the test
kit and connect it across Terminals T and T1 to simulate
a discharge air temperature of 60
o
F.
5. Remove the factory-installed jumper (wire 209A) from the
“fast response” Terminals 9 & 10.
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