- How To
- Diagrams: System Pressure Chart
Get a quick look at what an average A/C system looks like, along with the compressor manufacturer and what the specific R-134a requirements are for your car.
| R-134a TEMPERATURE PRESSURE CHART (Tabla de Temperaturas y Lecturas) |
||
|---|---|---|
| Ambient Temperature °F / °C (Temperatura Ambiental) |
Low-Pressure Gauge (Puerto de Servicio del Lado de Baja Presion) |
High-Pressure Gauge (Puerto de Servicio del Lado de Lado de Alta Presion) |
| 65°F (18°C) | 25-35 psi / 172-241 kPa | 135-155 psi / 931-1069 kPa |
| 70°F (21°C) | 35-40 psi / 241-276 kPa | 145-160 psi / 1000-1103 kPa |
| 75°F (24°C) | 35-40 psi / 241-310 kPa | 150-170 psi / 1034-1172 kPa |
| 80°F (27°C) | 40-50 psi / 276-345 kPa | 175-210 psi / 1207-1448 kPa |
| 85°F (29°C) | 45-55 psi / 310-379 kPa | 225-250 psi / 1551-1724 kPa |
| 90°F (32°C) | 45-55 psi / 310-379 kPa | 250-270 psi / 1724-1862 kPa |
| 95°F (35°C) | 50-55 psi / 345-379 kPa | 275-300 psi / 1896-2068 kPa |
| 100°F (38°C) | 50-55 psi / 345-379 kPa | 315-325 psi / 2172-2241 kPa |
| 105°F (41°C) | 50-55 psi / 345-379 kPa | 330-335 psi / 2275-2310 kPa |
| 110°F (43°C) | 50-55 psi / 345-379 kPa | 340-345 psi / 2344-2379 kPa |
| Ambient temp is the outside atmospheric temperature. | ||
| INTERPRETING PRESSURE READINGS | ||
|---|---|---|
| Low-Pressure Gauge |
High-Pressure Gauge |
Action Required |
| IN RANGE | IN RANGE | A/C is working properly. |
| LOW | LOW | Add Refrigerant. |
| LOW | HIGH | Need service, possible blockage of the expansion valve or orifice tube. |
| HIGH | LOW | Needs service, possibly faulty compressor. |
| HIGH | HIGH | System is overcharged. Slowly remove refrigerant. Venting is illegal in USA. |
| It is illegal to vent 134a refrigerant into the atmoshpere. | ||