Trane 4DCZ6036, Руководство по установке

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Page 20
Installer’s Guide
Thermostat
Operation of the unit heating and cooling cycles is automatic when
the system is set to
HEAT
or
COOL
(the optional automatic change-
over thermostat, when set to
AUTO
, automatically changes to heat
or cool with an appropriate room temperature change). The fan can
be set to
ON
, causing continuous evaporator (indoor) fan operation
at constant circulation - approximately 40 - 50% of nominal airflow
at selected dipswitch settings or set to
AUTO
causing fan opera-
tion to coincide with heating or cooling run cycles. Continuous fan
mode during cooling operation may not be appropriate in humid
climates. If the indoor air exceeds 60% relative humidity or simply
feels uncomfortably humid, it is recommended that the fan only be
used in the
AUTO
mode.
NOTE: The 4DCZ6 units require either a *CONT402, *CONT802
or *CONT803 Comfort Control. Do not install any other model of
thermostat with this 4DCZ6 unit. Otherwise, mis-operation could
result due to the dual fuel nature of this unit.
NOTE: A BAYSEN02ATEMPA outdoor temperature sensor must be
purchased separately and installed in order to use the *CONT802 and
*CONT803 Comfort Controls with this unit. A BAYSEN01ATEMPA
outdoor sensor is shipped with the *CONT402.
NOTE:
A field installed jumper wire (18 AWG minimum conduc -
tor) is required between the W1 and W2/X2 low voltage wires at
the 4DCZ6 unit when using the *CONT802 or *CONT803 Comfort
Controls since these two controls produce only a W1 output for
auxiliary heat. This will result in low fire gas heating for 10 minutes
or for as long as W1 is present if less than 10 minutes. Then, if the
W1 signal is still present from the Comfort Control, the 4DCZ6 unit
will transition automatically to high fire and operate on high fire for
the remaining duration of the call for auxiliary heat.
NOTE: The JP1 Dual Fuel jumper wire on the printed circuit board of
the *CONT402 must be cut for proper and reliable operation of this
dual fuel 4DCZ6 unit. There is no jumper to cut on the *CONT802
and *CONT803 Comfort Controls
TWO MODES OF OPERATION:
The unit can be installed and configured to operate in one of two
different heating modes: restricted and non-restricted. A brief
explanation of each mode follows.
RESTRICTED: In the restricted mode of operation an outdoor
temperature sensor is used to cause the unit to operate in the
heat pump mode above a selected outdoor temperature and
to operate in the gas heating mode below the selected outdoor
temperature. The gas heat will operate with the heat pump when
the unit requires a defrost cycle. The gas heat is used to offset
the effect of the unit going into the cooling mode during defrost.
For the *CONT402, the unit will be commanded to transition
to gas heat even when the outdoor temperature is above the
selected outdoor temperature changeover point if the heat pump
capacity is not enough to
maintain the indoor temperature at the
desired heating setpoint.
NON-RESTRICTED:
This mode of operation allows the unit to
operate in the heat pump mode during the first or second call,
or stage, of heat commanded by the indoor thermostat. During
the first stage of heat pump mode the heat pump will operate on
low speed. During the second stage, the heat pump will operate
on high speed. If the heat pump capacity is sufficient, gas heat
will not be required. If the heat pump capacity is not enough to
maintain the indoor temperature at the desired heating setpoint,
the thermostat will call for the third stage of heat. At that point,
the gas heat will begin to operate and the heat pump will be
Control Wiring (Class II)
Low voltage control wiring should not be run in conduit with power
wiring unless Class 1 wire of proper voltage rating is used. Route
the thermostat cable or equivalent single leads of No. 18 AWG
colored wire from the thermostat subbase terminals through the
rubber grommet on the unit. See Figures 2 or 5 for the control
entry (24V Entry) location. Make connections as shown on the
unit wiring diagram.
Do not short thermostat wires since this will damage the control
transformer.
Refer to Table 6 for recommended wire sizes and lengths for install-
ing the unit thermostat. The total resistance of these low voltage
wires must not exceed one (1) ohm. Any resistance in excess of 1
ohm may cause the control to malfunction because of the exces-
sive voltage drop.
Table 6. Thermostat Wire Size and Maximum Length
Contactor
Unit Ground Lug
Figure 20. Power Connections
Wire Size Maximum Length
18 75
16 125
14 200
Figure 21. Mounted Disconnect Location