DIY guideHumidifier
Change the furnace humidifier pad and check its drain
Turn the power and water off, swap the scaled pad for a new one and flush its drain, so the humidifier works and doesn't grow mould.
- 15 to 30 min
- 7 steps
- Every step animated
7 steps
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Turn the humidistat to Off, then the furnace's switch. If the humidifier has its own plug, unplug it.
Turn the small valve on the thin pipe that feeds the humidifier clockwise until it stops.
Unclip the humidifier's cover and slide out the pad in its frame.
Pull the old pad off the frame and fit a new one of the same size, the right way up.
Pour a cup of water in at the bottom, where the hose leaves. It should run freely to the floor drain.
Slide the pad in, clip the cover on, open the water valve, turn the furnace switch on and set the humidistat.
If water leaks onto the furnace or the drain won't run, turn the water off and ask Handyman for a heating pro. A steam humidifier's canister is theirs too.
What you need
- A new pad the same size (the old one's label or the manual says which)
- A cup of water
- A towel
- A flashlight
Call a pro if
- Water leaks onto the furnace or the floor
- The drain won't run freely
- It's a steam humidifier, with a canister
- It hums or clicks but no water flows
Handyman says: Leaking? I'll find a heating pro.
Free for every home. Handyman asks a few questions, then books a pro it trusts.
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