Refrigeration · COMPONENT REFERENCE

TXV and metering device troubleshooting

Controls refrigerant admission to the evaporator; a TXV responds to superheat rather than directly controlling suction pressure.

Failure causes

Choose a cause for symptoms, checks that separate it from similar faults, repair direction and verification.

Restricted valve or liquid feed →A restriction limits liquid delivery to the evaporator.TXV sensing bulb or equalizer fault →Poor sensing contact or an incorrect pressure-reference path makes the valve respond to the wrong conditions.Overfeeding or hunting →Valve operation and system conditions create excess or oscillating feed.

References and applicability

Original HVACSim explanations with manufacturer and instrument-maker references for further reading. These resources support the subject; their model-specific examples are not specifications for every system.

Parker Sporlan: Thermostatic expansion valves — Bulletin 10-10TXV operation and application; select the bulletin for the installed valve.

Editorial review: 2026-09-29. Verify the current manual for the installed model.