1996 CHEVROLET SUBURBAN heater

To operate the rear air conditioning system, the front air conditioning
system must be on. With the front air conditioning system
off, the rear
system controls can be used to circulate air in the rear of the vehicle.
0 To operate the rear
system using the front
control, just turn the
knob to the blower
position you want.
Rear Heater (Without Rear Air Conditioning)
If you have a rear
heater (without rear
air conditioning), the
control switch is
located
on the
instrument panel.
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To increase and decrease the flow of heated air to the rear floor vents, move
the switch marked REAR HEAT to the blower speed you want.
The knob has three speed positions.
To increase the flow of heated air, move
the switch toward HIGH.
To decrease the flow of heated air, move it toward
LOW. To turn the fan off, move the switch to OFF.
Rear Air Conditioning and Rear Heater
If your vehicle has a rear air conditioning and rear heater system
combination, controls are provided
to regulate the temperature, location and
speed of the air flow.
To adjust the air
temperature, turn the
temperature knob
on
the right side of the
control panel.
For warmer air, turn the knob clockwise toward the red side, and for cooler
air, turn the knob counterclockwise toward the blue side.
To regulate the air flow location, adjust the center knob on the control panel
Turn the knob counterclockwise for floor vent air flow or clockwise for
headliner vent air flow. Generally, the upper vents are used for air
conditioning and the floor vents for heating. The control knob can be set
to
any blend setting.
To adjust the air flow speed, turn the fan control knob on the left side of the
control panel
to the desired blower setting.
To activate
the rear control, move the fan knob on the front control to
REAR
CNTL.
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You can turn the defogger off at any time by pressing the button again. The
defogger will shut itself off after several minutes,
so that the glass does not
get too hot. If the defogger shuts off, and the window still isn’t clear, turn on
the defogger again.
Ventilation System
Your vehicle’s
ventilation system
supplies outside air
to
the inside of your
vehicle when it is
moving. With the side
windows closed, air
will flow into the front
air inlet grilles,
through the vehicle,
and
out the rear air
exhaust valve.
Outside air will also enter the vehicle when the heater or the air
conditioning fan is running, unless
you have the recirculation button pushed
in. For more information see “Recirculation Button” in this section.
Ventilation Tips
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Keep the hood and front air inlet free of ice, snow, or any other
obstruction (such as leaves). The heater and defroster will work far
better, reducing the chance
of fogging the inside of your windows.
When you enter a vehicle in cold weather, turn the blower fan to
HI for
a few moments before driving off. This helps clear the intake ducts of
snow and moisture, and reduces the chance of fogging the inside
of
your windows.
Keep the air path under the front seats clear
of objects. This helps air to
circulate throughout your vehicle.
Some models also have vents under the front seats. Keep the area at the
outlet grills clear
of floor mats or other objects. This will ensure proper
air
flow to the rear floor area.
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Run your engine only as long as you must. This saves fuel. When you run
the engine, make it
go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat
that you get and it keeps
the battery (or batteries) charged. You will need a well-charged battery
(or
batteries) to restart the vehicle, and possibly for signaling later on with your
headlights. Let the heater
run for awhile.
If you have a diesel engine, you may have
to run it at a higher speed to get
enough heat. Then, shut the engine off and close the window almost all the
way to preserve the heat. Start the engine again and repeat
this only when
you feel really uncomfortable from the cold. But do it as little as possible.
Preserve the fuel
as long as you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises every half
hour or so until
help
comes.
Power Winches
If you wish to use a power winch on your vehicle, only use it when your
vehicle
is stationary or anchored.
I NOTICE:
Using a power winch with the transmission in gear may damage
the transmission. When operating a power winch, always leave
the transmission in NEUTRAL
(N).
Use the regular brakes, set the parking brake, or block the wheels to keep
your vehicle from rolling.
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NOTICE:
If your engine catches fire because you keep driving with no
coolant, your vehicle can be badly damaged. The costly repairs
would not be covered by your warranty.
If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no steam, the problem may
not be too serious. Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high speed driving.
0 Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” in the Index.
If you get the overheat warning with
no sign of steam, try this for a minute
or
so:
I. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan speed and open the
window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N); otherwise, shift to the
highest gear while driving
- AUTOMATIC OVERDRIVE (a) or
DRIVE (3) for automatic transmissions.
If you no longer have the overheat warning, you can drive. Just to be safe,
drive slower for about ten minutes. If the warning doesn’t come back on,
you can drive normally.
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The coolant level
should be
at or above
the
COLD mark. If it
isn’t, you may have a
leak in the radiator
hoses, heater hoses,
radiator, water pump
or somewhere else in
the cooling system.
NOTICE:
Engine damage from running your engine without coolant isn’t \
covered
by your warranty.
If there seems to be no leak, start the engine again. See if the fan speed
increases when idle speed
is doubled by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn
off the engine.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
the
COLD mark, add a 50/50 mixture of clean water (preferably distilled)
and a proper antifreeze at the coolant recovery tank. (See “Engine Coolant”
in the Index for more information about the proper coolant mix.)
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NOTICE:
In cold weather, water can freeze and crack the engine, radiat\
or.
heater core and other parts. Use the recommended coolant.
E
When the coolant in the coolant recovery tank is at or above the COLD
mark, start your vehicle.
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Cooling System - Diesel Engines
When you decide it’s safe to lift the hood, here’s what you’ll see:
A. Coolant surge tank pressure cap
B. Engine fan(s)
C. Radiator
If the coolant inside the coolant surge tank is boiling, don’t do anything else
until
it cools down.
The coolant level
should be at or above
the
COLD mark. If it
isn’t,
you may have a
leak in the radiator
hoses, heater hoses,
radiator, water pump
1 or somewhere else in
the cooling system.
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