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🍁 Built for Canadian homes — written to Canadian codes and provincial rules. Not intended for use outside Canada.
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Ductless mini-split is dripping water indoors

Water dripping from the indoor unit looks alarming, but it is usually condensation that can't drain away — often a clogged drain line you can clear in an afternoon, not a refrigerant leak.

tuneWhat are you noticing?
Select anything that matches and the checklist below reorders to fit. Not sure? Skip it.
emergency_home

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Start here

In Canadian homes, start with the condensate drain. Follow the hose from the indoor head to where it exits outside and check for a blockage or standing water — a clogged drain line is by far the most common reason a mini-split drips indoors. Clearing it (a look now, then power off before you work near the electronics) usually solves it.

Ranked from real-world failure data. The order updates as you select what you’re noticing above.

Likely causes, in the order to check them

Showing the typical order
Beginner-friendly Doable, with care Safety-critical Call a pro

visibilityHow to check

warning Cut the power before you work near the headThe indoor head holds live electronics right beside the water you're chasing, so mixing hands, water, and power is the real hazard here. Switch the unit off at its breaker before clearing the drain near the indoor unit, and don't work on it while standing in or touching water. If the leak is already reaching wiring or an outlet, stop and call an HVAC pro instead.
  1. Find where the condensate hose exits the building — usually a small white pipe running down the wall from behind the outdoor unit. With the mini-split running in cooling, you should see a steady trickle; no water there while it drips inside points to a blockage.
  2. Cut power to the unit at the breaker before doing anything near the indoor head or its wiring — never work on a wet, energized unit.
  3. Apply gentle suction at the outdoor end of the hose with a wet/dry vacuum (seal the connection with a rag). A slug of slime or water pulling free, followed by free flow, confirms a clogged line.
buildflashlightbuildwet/dry vacuum schedule25 min

handymanHow to fix it

With the unit powered off, flush the condensate line clear: pull the blockage from the outdoor end with a wet/dry vacuum, then flush the line from the pan end with warm water (and a little diluted vinegar to slow regrowth) until it runs freely outside.

  1. Switch the mini-split off at the breaker and confirm it's dead before touching the indoor head or the pan — the electronics sit right next to the water.
  2. At the outdoor end of the condensate hose, seal a wet/dry vacuum over the opening with a rag and run it for a minute or two to pull the blockage out.
  3. From the indoor pan end, slowly pour warm water (a cup of 1:1 vinegar-and-water helps slow algae regrowth) and confirm it runs freely out the outdoor end.
  4. Restore power, run the unit in cooling, and watch for a steady outdoor drip and a dry pan indoors. If it still backs up, the line's slope or the pan may be the problem instead.
schedule40 min savings$0–25
gavel Check your province first AB: homeowner may do this · BC: homeowner may do this · ON: homeowner may do this · PE: homeowner may do this · QC: homeowner may do this
Clearing a condensate drain and cleaning filters are routine homeowner maintenance and permitted across Canada. By contrast, opening the sealed refrigerant circuit is restricted to certified technicians nationwide (federal ODS/halocarbon regulations plus provincial rules) — see the refrigerant cause's do_not_diy gate.

handymanHow to fix it

Flip up the front cover, slide out the mesh filters, rinse them under lukewarm water (or vacuum them), let them dry fully, and reseat them. Replace them if they're torn or permanently discoloured, and let any coil ice melt before running again.

  1. Turn the unit off, flip up the front cover, and lift out the mesh filters — most slide straight up and out.
  2. Rinse them under lukewarm water or vacuum the dust off, then let them dry completely before reinstalling — a damp filter just re-clogs.
  3. If the coil behind them is iced, leave the unit off until the ice fully melts and the pan drains, so you don't chase a flood.
  4. Reseat the (dry) filters, close the cover, and run the unit; set a reminder to clean them every month or two in season.
schedule15 min savings$0–30
Replacement mini-split mesh filterMatch the make/model of the indoor head; many are washable and only replaced if torn

verifiedWhy this one goes to a pro

A mini-split that keeps icing on clean filters and a clear drain may be low on refrigerant, and handling refrigerant is regulated work: it takes a certified technician and proper recovery equipment, both to fix the leak safely and because venting refrigerant is illegal. Leave the charge alone and book a licensed HVAC tech to find the leak and recharge it.

Your notes travel with the request — what you saw, what you ruled out, when it started — so the pro arrives with a head start instead of a mystery.

sort

Why the list is in this order

We don’t sort by likelihood alone. We sort the way a good, honest tradesperson thinks: rule out the free, safe, common causes first. That’s why the cheap checks outrank the expensive repairs — and why anything dangerous gets a hard stop instead of a pep talk. The order exists to save you money, not to sell you anything.