Background:
The post addresses a continuing look at the temperature of air passing through the air conditioning condenser.
Previous tests had the goal of trying to understand how the temperature of the AC condenser changes when the system is operating versus when it is off, and the rate at which temperatures change when the operating condition changes.
In this experiment, the temperature leaving the AC condenser is the property of interest.
The goal of this experiment is to measure the air temperature between the outlet side of the AC condenser and the inlet face of the stock location GTI intercooler.
The intercooler being used during this experiment is the GTI stock intercooler.
Test Procedure:
To try to prevent the temperature probe from contacting the back of the AC condenser or front of the intercooler the probe tip and wire are run through a plastic tube that will hopefully keep the probe tip from contacting the part surfaces.
Because the probe is placed between the AC condenser and the intercooler, there is no way to visually confirm the probe tip is not in contact with one of the parts.
With the temperature probe in place, the GTI is driven while switching between operating the air conditioning system and without.
Driving conditions are relatively low-speed around town with maximum speeds of approximately 45 mph.
Test Results:
In the charts, the temperature probe reading is identified as Cond (degF) with a light green line. The air conditioner operating state is indicated by Fan (%) and the brown line. Any time the Fan percentage is greater than 0% the air conditioning system is operating.
In the first chart, the air conditioner is off during the first half of the drive. The temperature between the AC condenser and intercooler is very close to the Ambient Air Temperature – indicated by the pink line.
When the air conditioning system is turned on the temperature increases by approximately 30 degF rapidly.
Shortly thereafter some of the data logging equipment stopped recording. The Oil Pressure (dark blue line) gives some indication of the vehicle’s operating condition when the vehicle speed is unavailable.
Turning off the air conditioner results in a steady decline in the temperature between the condenser and intercooler.
The next chart shows the effect on the sampled air temperature while cycling the air conditioner on and off several times.
The operating state of the air conditioner has a significant effect on the air temperature, leading to swings of 20-25 degF.
Conclusions:
The air temperature between the Mk7 air conditioning condenser and a stock location intercooler was measured during around-town driving.
The operating state of the air conditioner had a significant effect on the air temperature in the area where the temperature probe was located, causing upward swings of 20-25 degF when the system was operating and a drop to ambient air temperature when the system was not operating.