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Aprilaire
Humidifier

Model # 550 Official Aprilaire humidifier

Here are the diagrams and repair parts for Official Aprilaire 550 humidifier, as well as links to manuals and error code tables, if available.

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Owner’s manual

Model diagram and schematic

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ALL PARTS
Showing 10 of 24 parts  |
Transformer 4010
#14

Model 550 diagram

Transformer

Part #4010

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

Wick Pad 10
#1

Model 550 diagram

Wick pad

Part #10

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

Valve Sadd 4001
#18

Model 550 diagram

Valve sadd

Part #4001

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

Nozzle 4184
#16

Model 550 diagram

Nozzle

Part #4184

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

Drain 4223
#8

Model 550 diagram

Drain

Part #4223

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

Stainer 4004
#10

Model 550 diagram

Stainer

Part #4004

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

Valve 4040
#9

Model 550 diagram

Valve

Part #4040

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

Compression Fitting And Strainer (6) 4003
#11

Model 550 diagram

Compression fitting and strainer (6)

Part #4003

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

Cover Latch Spring 4225
#17

Model 550 diagram

Cover latch spring

Part #4225

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

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