THOR CLASS A Owner'S Manual Download

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H E AT I N G A N D C O O L I N G

C U S T O M E R C A R E | 8 7 7 . 8 5 5 . 2 8 6 7

while the control circuits usually operate on 12 volts DC.

Due to the electrical load of an air conditioner, they are not

on-board electrical generator system.

All air conditioners are rated in British Thermal Units

(BTU), which is a measure of their cooling capacity. The

higher this number, the higher the unit’s cooling ability.

Ensure that the shore power source is adequate for the

power needed to operate the air conditioner(s).

TEMPERATURE DIFFERENTIAL

The ability of the air conditioner to maintain the desired

inside temperature depends on the heat gain of the motor-

home. The size of the vehicle, amount of window area,

amount of insulation, amount of direct exposure to the

sun, outside temperature, and the number of people occu-

pying the inside space are factors that may increase the

heat gain to such an extent that the ability of the air condi-

tioner to cool the motorhome to the desired temperature is

compromised. Under most operating conditions, you can

expect a 15-to-20 degree temperature differential between

the outside air and the discharge air of the air conditioner.

As long as this temperature differential is being maintained,

the air conditioner is operating at its capacity. If the desired

inside temperature (normally 75°-80° F) cannot be main-

tained, then the heat gain within the motorhome is too

great for the capacity of the air conditioner.

To increase the effectiveness of the house air conditioner,

try reducing the heat gain of the motorhome by:

• Park the motorhome in a shaded location.
• Use window and patio awnings when outside ambient

temperature is above 95° F to help deflect the heating

effects of the sun. If window awnings are not installed

or cannot be used, cover windows with shades or blinds.

• Try to avoid using the cook top or oven when the

ambient temperature is over 95° F.

• When parked, keep windshield covered when facing

the afternoon sun.

• Minimize opening exterior doors when the air condi-

tioner is running.

NOTE:
• 120 volts AC must be present in order to operate

air conditioners and/or heat pumps. The energy
can be supplied by shore power or the on-board
generator.

• Air conditioners are designed to cool approximately

20 degrees Fahrenheit lower than the outside
ambient air. On extremely hot days, the air
conditioner may not be able to cool the motorhome
to the desired temperature.

• During warm weather, it is best to start the air

conditioner early in the day, allowing it to cool-
down and keep the interior of the motorhome at
a comfortable temperature before the outside
temperature creates too much of a temperature
differential.

Manual Controls for Roof-Mount Air

Conditioners

Three basic controls on the air conditioner’s ceiling

assembly operate the air conditioner’s functions. The three

controls are:

SELECTOR SWITCH

The selector switch determines which mode of operation

the air conditioner will be in. By rotating the selector switch,

the operator can obtain any system function desired.

System functions vary depending upon options of the air

conditioning unit.

THERMOSTAT (TEMPERATURE CONTROL)

In the cooling mode, the thermostat regulates the ON and

OFF temperature setting at which the compressor will

operate. For ‘Heat/Cool’ models (heat pumps and units

with built-in heating coils), the thermostat also controls the

ON and OFF temperature setting of the heater assembly.

LOUVERS

The louvers are located at both ends of the ceiling assembly

shroud and are used in directing the discharge air from the

air conditioning unit.

NOTE: Some air conditioners are supplied with an
optional Elect-A-Heat heating assembly, which is
intended to take the chill out of the indoor air when
the air is a few degrees too cool for comfort. This
heating assembly is an effective ‘chill chaser,’ but is
not a substitute for a furnace.