Aprilaire
Humidifier

Model # 440 Official Aprilaire humidifier

Here are the diagrams and repair parts for Official Aprilaire 440 humidifier, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 22 parts  |

Wick Pad 12
#9

Model 440 diagram

Wick pad

Part #12

The manufacturer no longer makes this part, and there's no substitute part

Transformer 4010
#11

Model 440 diagram

Transformer

Part #4010

The manufacturer no longer makes this part, and there's no substitute part

Water Distribution Tray 4081
#8

Model 440 diagram

Water distribution tray

Part #4081

The manufacturer no longer makes this part, and there's no substitute part

Compression Fitting And Strainer (6) 4003
#5

Model 440 diagram

Compression fitting and strainer (6)

Part #4003

The manufacturer no longer makes this part, and there's no substitute part

Stainer 4004
#18

Model 440 diagram

Stainer

Part #4004

The manufacturer no longer makes this part, and there's no substitute part

Valve Sadd 4001
#1

Model 440 diagram

Valve sadd

Part #4001

The manufacturer no longer makes this part, and there's no substitute part

Tube-drain 4047

#NI

All parts diagram

Tube-drain

Part #4047

The manufacturer no longer makes this part, and there's no substitute part

Clip And Screw Set 4086
#17

Model 440 diagram

Clip and screw set

Part #4086

The manufacturer no longer makes this part, and there's no substitute part

Knob 4166
#6

Model 440 diagram

Knob

Part #4166

The manufacturer no longer makes this part, and there's no substitute part

Lower Housing 4163
#15

Model 440 diagram

Lower housing

Part #4163

The manufacturer no longer makes this part, and there's no substitute part

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