HVACDIAGNOSTIC
Condition

Water Leak Only When AC Running

Leak occurs only during cooling operation. Condensate drain or pan.

Possible Causes

Clogged Condensate Drain

Algae and dust can block the drain, causing water to back up and trip safety switches.

Root Cause Analysis →
Repair Options
Condensate Drain Line Clearing →

Dirty Evaporator Coils

Dust buildup on the coils restricts airflow and stops heat absorption.

Root Cause Analysis →
Repair Options
Evaporator Coil Cleaning →

Severely Clogged Air Filter

A dirty filter restricts airflow, putting strain on the blower motor and reducing efficiency.

Root Cause Analysis →
Repair Options
High-Efficiency Air Filter Replacement →

Repair Options

Condensate Drain Line ClearingView Repair Manual →Evaporator Coil CleaningView Repair Manual →High-Efficiency Air Filter ReplacementView Repair Manual →

Related Components & Parts

drain lineevaporator coilfilter

Other HVAC System Leaking Water Conditions

Water Pooling at Indoor UnitWater Dripping from CeilingWater Leak After Filter Change
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