Trane IntelliPak 2 Series, Инструкция по установке, эксплуатации и обслуживанию

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RT-SVX24Q-EN 101
Figure 70. Energy recovery wheel economizer operation
Outside Air Intake Damper
(Mist Eliminator not shown)
Outside Air Bypass Damper
Path to
Filters
& Coil
Un-
Conditioned
Outside Air
Path to
Filters
& Coil
Unit Return
Airflow
Return Air Damper
Exhaust Air
Bypass Damper
Exhaust Air
Path to Exhaust Fan
Building Return Air
Gas Heating Sequence of Operation
Standard
Two Stage Gas Furnace
The control system for the rooftop units are wired to
ensure that the heating and cooling do not occur
simultaneously. Refer to the wiring diagram that
shipped with the unit while reviewing the following
sequence of operation.
Honeywell Ignition System
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When a heating requirement exists, the Rooftop
Module (RTM) starts the supply fan and sends a
request for heat to the Heat Module. The Heat Module
closes contacts and starts the combustion blower
motor. The combustion blower motor starts on low
speed through the normally closed combustion blower
relay contacts.
The supply airflow switch and the combustion air
switch closes. Power is applied through the high limit
cutout to the Honeywell ignition control board. The
ignition control board starts a pre-purge timing cycle.
At the end of the pre-purge cycle, the ignition
transformer and the pilot solenoid valve are energized.
This starts a 10 second trial for pilot ignition. When the
pilot flame is established and sensed by the flame
sensing rod, stage 1 of the main gas valve and the 60
seconds sequencing time delay relay is energized.
The system will operate in the low heat mode until an
additional call for heat, established by closing the
contacts on the Heat Module. The sequencing time
delay relay will energize the combustion blower motor
relay which switches the combustion blower motor to
high speed and energizes the 2nd stage solenoid on the
gas valve after approximately 60 seconds.
If the flame rod does not detect a pilot flame within the
10 second trial for ignition period, the control will
lockout. If a flame failure occurs during operation, the
gas valve, the sequencing time delay relay, and the
combustion blower relay is de-energized. The system
will purge and attempt to relight the pilot. If a flame is
not detected after this attempt, the Honeywell ignition
control will lock out. The combustion blower motor will
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