System Diagnostic Tool
Input your readings → Get instant diagnosis
Pressure Readings (Gauge)
Temperature Readings
At condenser outlet
At compressor inlet
Calculated Values
Superheat:
-
Subcooling:
-
Condensing Temp:
-
-
Evaporating Temp:
-
-
Compression Ratio:
-
Approach (Cond):
-
Discharge Estimate:
-
System Diagnosis
⏳
Enter Readings
Input pressure and temperature values to get diagnosis
Recommended Actions
Diagnostic Quick Reference
| Superheat | Subcooling | Likely Cause | Action |
|---|---|---|---|
| HIGH | LOW | Low refrigerant charge | Check for leaks, add charge |
| LOW | HIGH | Overcharge | Recover excess refrigerant |
| HIGH | NORMAL/HIGH | Metering device restriction or low airflow | Check TXV, filter, evap coil |
| LOW | LOW | TXV stuck open or flooded evaporator | Check TXV, superheat setting |
| NORMAL | HIGH | Condenser issue (dirty, restricted airflow) | Clean condenser, check fan |
| NORMAL | NORMAL | System operating correctly | No adjustment needed |
TXV Systems
Target Superheat: 10-15°F (5-8°C)
Target Subcooling: 10-18°F (5-10°C)
Subcooling is the primary charge indicator
Fixed Orifice Systems
Target Superheat: 8-14°F (4-8°C)
Subcooling: Varies with charge
Superheat is the primary charge indicator
Compression Ratio Guidelines
2.0 - 3.5
Normal A/C Operation
Optimal efficiency range
3.5 - 4.5
High Load / Hot Day
Monitor discharge temp
> 4.5
Warning Zone
Check for restrictions, airflow