Honeywell HE220A Humidifier

	Part number HC22A1007
	Honeywell support: 800 468-1502

Instructions for changing out humidifier filter.

The replacement filter number is also noted on the humidifier-maintenance decal on cold-air return. Perform maintenance on this unit at end of heating season in spring or before heating season begins in fall.

I supplied soft water to the humidifier in order to minimize the amount of hard-water deposits likely to degrade the filter prematurely. I supplied cold water to ensure there is no impact to the amount of hot water in the house.

Click on illustrations to make them bigger. The first illustration is useful to almost all the instructions here.

Steps to replace filter

  1. The only nasty thing about this duty is that part of the water heater duct must be removed temporarily. Turn the water heater to PILOT instead of ON (do not turn it OFF).
  2. Remove screw in water heater flue immediately above the humidifier filter unit. Remove flue from top of water heater (pop out the four legs) and from rest of flue. Set aside.
  3. Undo the large, knurled aluminum nut underneath filter unit. This screw does not come out, but only undoes the cover. Remove the cover and set aside.
  4. The filter is housed in a black plastic frame that makes the whole thing look vaguely like a car radiator. Gently pull on the far side of the frame until the unit comes out, top first, into your hands. Disconnect the water tube from the top of the unit.
  5. Disassemble the filter frame, remove the naked filter and discard only the latter. Clean the black plastic frame thoroughly as it is not disposable. Ensure that no holes are plugged.
  6. Reassemble the filter frame with a new filter. Reinstall the filter frame into the greater humidifier filter unit by first reconnecting the water tube, then, minding the water tube does not get caught between the frame and the unit, insert the frame bottom first, then pressing gently on the top of the frame until it seats.
  7. Reposition the unit cover and reinstall the water heater flue by reconnecting it to the rest of the flue with the screw, then firmly working the four legs of the connector back into their holes in the top of the water heater.

Other service items

Vacation and summer tasks

Returning from vacation or beginning the heating season

  1. Turn the water on (see "Vacation and summer tasks").
  2. Turn the humidity control to the desired setting (see "Other service items").
  3. Turn air-flow valve to "winter" position (see Vacation and summer tasks).
  4. To fine-tune the amount of water, keep turning down (clockwise, to off) the water valve until very little comes out of the drain hose. This will a) save water and b) save on the amount of water running through the filter (which in part is what reduces its life).

How to tell that the humidifier is working properly

How the humidifier works...

  1. Pressurized air enters from the warm-air plenum atop the furnace traveling through the duct to the humidifier filter unit.
  2. The air in the unit travels through the filter into the cold-air return plenum. As it passes through the filter, it evaporates water dripping through the filter pad (the part that's replaceable). This air becomes moister for the water added into it. (The solenoid near the water tubing at the bottom of the filter unit controls whether water can flow into the filter pad.)
  3. The moister air is drawn by the furnace blower through the furnace filter and into the burners below the warm-air plenum and is sent up through the house duct system.
  4. In fact, the humidifier works in exactly the same way as the evaporative (swamp) cooler. The latter produces cool air because the air it pulls in through its wet filter pads evaporates the water. It takes heat energy to evaporate the water and thus the air gets cooler (but also more humid, which is why evaporative coolers won't work in places like Houston, Texas).