9000 L4-1985cc 2.0L DOHC (1986)
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Evaporator Core: Description and Operation
Evaporator - 1
When the refrigerant comes from the expansion valve in to, the evaporator, it expands. The pressure in the evaporator is much lower due to the
suction effect of the compressor. As refrigerant expands, it becomes gaseous (boils). However, in order for evaporation to take place, heat must be
supplied. This heat is taken from the air around the evaporator. The cold air is then blown into the cabin by the fan. Refrigerant is then directed on
in gaseous form to the compressor.
The evaporator has fins and a refrigerant manifold. When heat is absorbed, condensation builds up on the outside of the evaporator. This
condensation is drained out through a hose in the lower part of the evaporator casing and out into the engine compartment. The drain hose is
required in order to protect against dirt and to prevent a higher noise level in the cab and to maintain cooling. In addition, odor may be generated if
condensation is not satisfactorily removed.