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water dripping inside from the split system

The question, put plainly: Why is water dripping from my air conditioner?

The short answer

An indoor unit dripping inside is almost always a blocked or badly fallen condensate drain, and it is a maintenance problem rather than a refrigerant problem.

TradieAnswers editorial · written in-house and sourced to the authorities listed below

Checked against 4 published sources, listed in full at the end of this page. How we source this

Cooling removes moisture from the air, and that moisture has to go somewhere. It collects in a tray under the indoor coil and drains away by gravity through a small pipe. Anything that interrupts that path puts the water on your wall.

The usual causes

  • A blocked drain line. Biological growth builds up inside it over years and eventually blocks it, which is the single most common cause.
  • Insufficient fall in the drain line, so water sits and eventually backs up.
  • A dirty filter or coil, which makes the coil run colder, ice up, then dump water when it thaws.
  • An installation where the drain has to run uphill and relies on a pump that has failed.
  • Low refrigerant, which causes icing and then dripping. This one is a fault rather than maintenance.

What you can do first

  1. Turn the unit off so it stops producing water.
  2. Remove and clean the filters, which is user maintenance on every split system and is often overlooked for years.
  3. Look at where the drain discharges outside. If nothing is coming out while the unit runs, the line is blocked.
  4. Check the outdoor end of the drain for insects, debris or a crushed pipe.

Who does this work

You may need an ARCtick-licensed air conditioning technician

Because clearing a blocked drain line is often simple, but anything involving refrigerant requires an ARCtick licence.

This is licensed work in every Australian state and territory. Check a licence in your state

Sources

Every source below was fetched and its response recorded on the date shown. Where a government site blocks automated clients, that is noted rather than reported as a successful check.

  1. Refrigerant Handling Licence · Australian Refrigeration CouncilChecked 2026-08-10 · responded 200 OK
  2. ARC Industry Site · Australian Refrigeration CouncilChecked 2026-08-10 · responded 200 OK
  3. Energy Rating · Australian GovernmentChecked 2026-08-10 · responded 200 OK
  4. Standards Australia · Standards AustraliaChecked 2026-08-10 · responded 200 OK

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