System Performance Test

1. Install manifold gauge set.
2. Run engine at 2000 RPM and set controls for maximum cooling and high blower speed.
3. Open all windows and doors.
4. Place dry-bulb thermometer in cool air outlet.
5. Place psychrometer (combination wet and dry-bulb thermometers) close to cooling unit inlet.
6. On 626 & MX-6 models ensure reading on high pressure gauge is 199 - 228 psi.
7. On RX-7 models, pressure should be 149 - 192 psi.
8. On MX-3 models, pressure should be 185 - 214 psi.
9. If reading is too high, pour water on condenser and, if reading is too low, cover front of condenser.
10. Ensure reading of dry-bulb thermometer at air inlet is 77 - 95°F.
11. Calculate relative humidity from psychrometric graph, Fig. 2, by comparing wet and dry-bulb readings of psychrometer.
12. Measure dry-bulb temperature at cool air outlet, then calculate difference between inlet dry-bulb and outlet dry-bulb temperatures.
13. If intersection of relative humidity and temperature difference is between two hatched lines, Fig. 1, cooling performance is satisfactory.