Q T Basic Operation; Power On; System Off; Selecting Setpoint - Dometic Blizzard Turbo Installation And Operation Manual

Blizzard Turbo Split System Manual
Q B O
T ASIC PERATION
P O
OWER N
When AC power is applied to the system at the circuit breaker, the Qt Control/Display microprocessor performs a self-check and
retrieves, from permanent memory, the last operating configuration. This process takes about four seconds, after which the
system will begin operating just as it had been when power was last turned off.
NOTE: These systems have a two-minute compressor restart delay to allow the system refrigerant pressures to
equalize before starting. This delay begins when the compressor shuts down for any reason. This delay is increased
by the Compressor Time Delay function so that vehicles with multiple units can be set to prevent all units from turning
on at the same time if power is lost and restored.
S O
YSTEM FF
Press the OFF key to turn the system off. Note that the data display remains energized even when the system is off. The fan
can be turned on manually when the system is in the OFF mode.
NOTE: The Qt has built-in protection against sudden power interruptions. The system automatically stores the current
operating configuration in permanent memory every time you make changes. (The new operation mode must be in
affect for 30 seconds before it is saved into permanent memory.) When AC power is lost, the Qt system retains these
settings, and when AC power is restored it resumes operation using the same settings as before.
S
ELECTING
Press either plus (+) or minus (-) key once and the setpoint will be displayed. Press either key once more to change the
setpoint. Pressing and holding either key will scroll the setpoint temperature. While in setpoint mode, a dot will appear in the top-
middle of the display. After three seconds of no key presses, the new setpoint is applied, the dot disappears in the display and
the current internal temperature is shown.
D
ISPLAYING
When the unit is in any mode such as OFF, HEAT, COOL or AUTO, the display will show the internal temperature. In order to
see the internal temperature when the unit is in program mode, press the fan key twice to save existing data and exit program
mode.
COOL M
ODE
Press the MODE key until the COOL LED lights. Note that the internal temperature must be above the setpoint by
approximately three degrees before the compressor is energized and cooling begins. At this point a dot will be illuminated in the
upper-left corner of the display indicating the compressor is on. When the internal temperature equals the setpoint the
compressor is de-energized and the dot will go off. When the compressor cycles off in any mode, a two-minute compressor
delay is initiated. When the compressor is called to run again, it will be delayed for the remaining time left in the two-minute
delay and shown on the display.
HEAT M
ODE
Press the MODE key until the HEAT LED lights. Note that the internal temperature must be below the setpoint by approximately
three degrees before the heat element is energized and heating begins. At this point a dot will be illuminated in the upper-left
corner of the display indicating the heating element is on. When the internal temperature equals the setpoint the heating
element is de-energized and the dot will go off.
NOTE: When the system is in AUTO mode, the HEAT LED will illuminate when the heat element is energized. When the
heat element is de-energized, the HEAT LED will go off.
AUTO M
ODE
Press the MODE key until the AUTO LED is lit. Note that the COOL or HEAT LED will be lit along with the AUTO LED when the
compressor or heating element is energized. If the internal temperature equals the setpoint, only the AUTO LED will be on.
A
UTOMATIC
The internal fan runs continuously in any mode unless the system is turned off (except in Power Saver mode, see heading
"Power Saver Mode").
Fan operation in continuous AUTO mode is automatic (top LED will be lit) and is based on a temperature differential of internal
temperature and setpoint.
In COOL mode or AUTO COOL, the fan speed increases one speed for every degree of change of internal temperature above
the setpoint. After 3°F above setpoint is obtained, high fan speed is reached. As internal temperature decreases or approaches
L-3448 ENGLISH
S
ETPOINT
T

EMPERATURE

F S (I
AN PEED NTERNAL
OPERATING THE SYSTEM WITH QT CONTROLS
A F )
IR LOW
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