Superheat & Suction Pressure Analysis
Possible Causes:
1. Oversized Valve.
2. TEV seat leak.
3. Lowsuperheat adjustment.
4. Bulb installation.
a. Poor thermal contact.
b. Warm location.
5. Wrong thermostatic charge.
6. Bad compressor - low capacity.
7. Moisture, dirt, wax.
8. Incorrectly located external exualizer.
Possible Causes:
1. Moisture, dirt, wax.
2. Undersized valve.
3. High superheat adjustment.
4. Gas charge condensation.
5. Dead thermostatic element charge.
6. Wrong thermostatic charge
7. Evaporator pressure drop - no external equalizer.
8. External equalizer location.
9. Restricted or capped external equalizer.
10. Low refrigerant charge.
11. Liquid line vapor.
a. Vertical lift.
b. High friction loss.
c. Long or small line.
d. Plugged dried or strainer.
12. Low pressure drop across valve
a. Same as #11 above
b. Undersized distributor nozzle or circuit.
c. Low condensing temperature.
Possible Causes:
1. Low load.
a. Not enough air.
b. Dirty air filters.
c. Air too cold.
d. Coil icing.
2. Poor air distribution.
3. Poor refrigeration distribution.
4. Improper compressor-evaporator balance.
5. Evaporator oil logged.
6. Flow from one TEV affecting another's bulb.
