Quick Answer
Okay, so here's the quick version. A puddle of water from your indoor AC unit is almost always a clogged condensate drain line. It's supposed to drain the humidity it pulls from your air, but gunk builds up, causing it to back up. Happens all the time. But, if you see a block of ice on the unit, that's a different beast—probably a dirty filter causing low airflow, or you're low on refrigerant. For a simple clog, you can fix it yourself for under $20. If it's a refrigerant issue, a severely damaged drain pan, or a faulty condensate pump, you absolutely need a pro. Don't ignore it either way.
Common Symptoms
Possible Causes
Step-by-Step Diagnosis
Step 1
Turn off all power to the AC system at the circuit breaker.
Step 2
Locate the indoor air handler and inspect the area for water and ice.
Step 3
If you see ice on the coil, turn the system fan to 'ON' and AC to 'OFF' to thaw it.
Step 4
Check and replace the air filter if it is dirty.
Step 5
Inspect the primary drain pan under the coil for cracks, rust, or standing water.
Step 6
Locate the condensate drain line outside and check if it is dripping.
Step 7
Use a wet/dry vacuum on the outdoor drain line exit to suck out any clogs.
Step 8
If you have a condensate pump, check if the reservoir is full and if the pump motor runs.
DIY vs Professional Costs
| Repair Type | DIY Cost | Professional Cost | Time Required |
|---|---|---|---|
Clear Clogged Condensate Drain Line | $5-20 | $100-300 | 1 hour |
Replace Dirty Air Filter | $10-60 | $75-150 | 5 minutes |
Replace Drain Pan | NOT DIY | $400-1000+ | 4-6 hours |
Replace Condensate Pump | $60-150 | $250-600 | 1-2 hours |
Refrigerant Leak Repair & Recharge | NOT DIY | $500-2000+ | 2-5 hours |
When to Call a Professional Hvac
- If your coil freezes over, you thaw it, and it freezes again even with a clean filter.
- If you suspect a refrigerant leak (hissing sounds, sweet smell, or repeated freezing).
- If the main drain pan underneath the evaporator coil is cracked or rusted through.
- If you've tried clearing the drain line and it remains clogged or leaks persist.
- If you're not comfortable working with electrical components or disassembling the unit.
Prevention Tips
- Replace your air filter every 30-90 days, especially during heavy use.
- Pour a cup of distilled vinegar down the condensate line cleanout every few months to prevent algae buildup.
- Schedule an annual professional AC tune-up to have coils and drains cleaned and checked.
- Keep the area around your outdoor unit clear of leaves, grass, and debris.
Frequently Asked Questions
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