Trane 4DCZ6036, Руководство по установке

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Installer’s Guide
Call for gas heating after 2nd stage (heat pump):
If the heat pump capacity is not enough to handle the building
load, the heat pump is turned off and the gas heat is brought
on. The thermostat will call for low fire 1st stage gas heat
by removing power from (Y/Y1) and by powering (W1). (G)
will remain energized for a minimum of 2 minutes so that the
transition to gas heat will not interrupt indoor airflow.
(W1) from the thermostat signals the control module (IGN) to
run its self-check routine. After the control module has verified
that the pressure switch (PS) contacts are open, the limit switch
(TCO) contacts are closed, and the flame rollout (RO) switch is
closed, the induced draft blower (CFM) will be energized on high
speed for approximately 5 seconds.
After the induced draft blower (CFM) has come up to speed,
the control will verify that the pressure switch (PS) contacts are
closed and will switch the induced draft blower to low speed for a
20 second prepurge. The gas valve (GV) is energized in the first
stage to permit gas flow and the spark igniter (IP) is energized.
The flame detector (FD) confirms that ignition has been achieved
within the 7 second trial period.
When the flame detector confirms that ignition has been
achieved, the delay to indoor blower ON period begins timing.
After approximately 45 seconds, the control module (IGN) will
take over control of the indoor blower motor (IDM). The control
module (IGN) will command the indoor blower to operate at low
speed throughout the heating cycle.
To maintain the indoor temperature at the desired setpoint, the
thermostat may operate the low fire gas heating continuously or
cycle low fire gas heating off and on (cycling on 2nd stage heat).
Cycling on low fire gas heat:
When the thermostat cycles off
during low fire first stage gas heating, power will be removed
from (W1), the gas valve (GV) will close, and the flame will
extinguish. The induced draft blower (CFM) will continue to run for
a postpurge period of approximately 5 seconds before shutting
off. The indoor blower motor (IDM) will continue to operate as the
heat exchanger cools down (the delay is field selectable for 45 or
90 seconds) before being turned off by the control module.
NOTE
: During gas heating operation, the indoor blower is
controlled by the normal sequence of gas furnace operation,
and not by the thermostat.
NOTE: The *CONT402 may transition from gas heating to
heat pump heating and then back to gas heating instead of just
cycling the gas heat on and off if the building load is relatively
low (see the Transitioning from low fire gas heating to heat
pump operation for a complete description).
Call for high fire 2nd stage gas heating after low fire:
The thermostat adds (W2/X2) to (W1) signaling a call for second
stage gas heat. The induced draft motor (CFM) is energized
on high speed and the gas valve (GV) on second stage. After
approximately 30 seconds the control energizes the indoor
blower on high speed.
To maintain the indoor temperature at the desired setpoint, the
thermostat may operate the high fire gas heating continuously or
cycle between high fire gas heating and low fire gas heating.
Cycling on high fire 2nd stage gas heat:
When the thermostat cycles on high fire gas heating, power
will be removed from (W2/X2) and (W1) will remain powered.
The control module (IGN) will switch the gas valve (GV) to first
stage and the induced draft blower (CFM) to low speed. After
approximately 30 seconds the indoor blower motor is reduced to
low speed.
NOTE:
During gas heating operation, the indoor blower is
controlled by the normal sequence of gas furnace operation,
and not by the thermostat.
Transitioning from high fire 2nd stage gas to low fire 1st
stage gas:
The thermostat will begin to operate continuously on low fire gas
heating or will begin cycling on high fire gas heating.
Transitioning from low fire gas heating to heat pump
operation:
When the thermostat is cycling on low fire gas heat, the load
may decrease to the point where the thermostat determines that
the heat pump would have sufficient capacity to maintain the
indoor temperature at the desired setpoint. When this occurs,
power will be removed from (W1). This will cause the gas valve
(GV) to close and the control module to de-energize the induced
draft blower (CFM) after approximately 5 seconds postpurge.
The indoor blower motor (IDM) will continue to operate (with no
(G) signal) for the blower off period (45 or 90 seconds) while the
heat exchanger cools down. At approximately 45 seconds after
power was removed from (W1), the thermostat will apply power to
(Y1). This powers the compressor contactor (CC) which starts the
outdoor fan motor and compressor. The thermostat will also apply
power to (G) at this time so that the transition from gas heat to
heat pump will not interrupt indoor airflow. The purpose of the 45
second delay is to give the indoor coil sufficient time to cool down
before resuming compressor operation.
Turning off from 1st stage:
Same sequence as cycling on 1st stage heat (described
previously) except that the thermostat will make the transition to
off as described previously and will keep the heat pump turned
off.
commutated motor control (ECMC). (G) provides power to the
(ECMC) for low speed (ECM) indoor fan motor operation.
The energized compressor contactor (CC) completes the circuit
to the compressor for 1st stage (Low) operation and the outdoor
single speed fan motor (ODM). The indoor fan motor (ECM) will
operate on low speed. The room thermostat will continue to cycle
the compressor and fans to maintain the desired temperature.
Call for 2nd stage after 1st stage (heat pump):
On a call for 2nd stage heating, power is supplied from the room
thermostate (Y2) terminal to the compressor rectifier (ACR) and
the (ECMC). This energizes the (ACR) switching the compressor
to 2nd stage (High) operation. The room thermostat will continue
to cycle the system between 1st and 2nd stage to maintain the
desired temperature.