Goal: Clear condensate drainage blockages and ensure proper water removal from the AC system
Locate the condensate drain line and drain pan:
- Find the condensate drain line (usually a PVC pipe near the indoor unit)
- Locate the drain pan underneath the evaporator coil in the indoor unit
- Check for water pooling around the indoor unit indicating drainage problems
- Expected result: Drainage system components identified and any water accumulation noted
Inspect drain pan for clogs and damage:
- Remove the drain pan if accessible (may require removing access panel)
- Check for algae growth, mold, or debris accumulation
- Look for cracks or damage that could cause leaks
- Expected result: Drain pan condition assessed and any blockages or damage identified
Clear drain line blockages with wet/dry vacuum:
- Connect a wet/dry vacuum to the end of the drain line (outside the house)
- Create a tight seal using duct tape around the vacuum hose and drain line
- Run vacuum for 2-3 minutes to suction out clogs and debris
- Expected result: Blockages removed and water flows freely through drain line
Flush drain line with cleaning solution:
- Pour 1 cup of white vinegar into the drain line at the indoor unit
- Let the vinegar solution sit for 30 minutes to dissolve algae and buildup
- Flush with clean water to remove loosened debris and cleaning solution
- Expected result: Drain line cleaned and sanitized to prevent future blockages
Clean and sanitize the drain pan:
- Wash the drain pan with warm soapy water to remove all debris
- Apply a bleach solution (1:10 ratio) to kill mold and algae
- Rinse thoroughly and dry completely before reinstalling
- Expected result: Drain pan clean, sanitized, and ready for proper operation
Test drainage system operation:
- Pour water into the drain pan to test proper drainage flow
- Verify water flows smoothly through the drain line without backing up
- Check that drain line outlet outside is clear and water exits properly
- Expected result: Complete drainage system tested and functioning properly
If vacuum doesn't remove blockage: Use a drain snake or call professional for power cleaning
If drain pan keeps filling: Check for improper drain line slope or failed condensate pump
If mold keeps returning: Install UV light in drain pan area or improve ventilation
You'll know you're done when: Drainage system is completely clear and functioning properly
- Drain pan cleaned and free of algae, mold, or debris
- Drain line cleared of all blockages using vacuum suction
- Drain line flushed with vinegar solution and rinsed clean
- Drainage system tested with water flow verification
- No water pooling or backup around indoor unit
Ready for next step? You've ensured proper condensate drainage and can now perform advanced component testing and diagnostics.