Components Automotive Air Conditioning Condensers
Condensers
The Condenser function is to act as a heat exchanger and allow heat to flow from the hot
refrigerant to the cooler outside air.
R134a entering the condenser will be a high-pressure high temperature vapor. As the R134a
vapor travels through the tubes of the condenser heat is given off to the cooler ambient air; the
refrigerant vapor condenses and changes to a liquid state.
At this point a large amount of heat is given off by the R134a. The refrigerant will now be a hot,
high pressure liquid.
Design types
Serpentine
This type of condenser consists of one long tube which is coiled over and back on itself with
cooling fins in between the tubes.
Parallel flow design
(Recommended for R134a)
This design is very similar to a cross flow radiator. Instead of refrigerant travelling through one
passage (like serpentine type), it can now travel across numerous passages. This will give
R134a - R12 Comparison
- As R134a operates on higher pressures, less internal flow, restrictive and improved heat
rejection condensers are required.
- Most manufacturers select the parallel flow design for this.
Foam seals:
These seals are fitted in between the
condenser and radiator to prevent the
heated ambient air exiting above, below or
to the sides of the space in between
(normally 25mm) the radiator and
condenser.
As ambient air is drawn through condenser
by the condenser or radiator fan, its
temperature increases. If gaps are present
between the condenser and radiator this
heated air can be circulated back through
the condenser. This results in the increased
condenser temperature and causes
reduction in the performances of the A/C
system.
Condenser electric fan:
Most vehicles with air conditioning require
an electric fan to assist air flow, either
pushing or pulling the air through the
condenser, depending on which side of the
condenser the fan is placed.
The majority of vehicles using R134a
require this additional condenser cooling
due to the higher operating pressures of
R134a. Also most modern vehicles now
have smaller grilles or bumper bar
openings. This causes poor air flow
conditions especially by the amount of air
flow over the condenser.
The condenser fan is operated with A/C
engaged in various ways:
- Medium pressure switch;
- Indirect connection to the compressor
clutch
- Via the Electronic Control Module (ECM);
- Signal from the A/C switch activation.
R134a - R12 Comparison
Increased use (operation time) with R134a systems due to higher refrigerant temperature
by kandi younes
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