Product Description

Aprilaire brand wall mount analog humidistat. Can be duct mounted by using the duct mount adapter plate part number 4039 (not included). Will work on any brand of humidifier, low or high voltage control system. Designed for 24 volt operation and rated at 5.2 amps. Setpoint range of 15% to 50% with an 8% differential. This humidistat has been discontinued and is out of production. It was replaced by part 4655 so that is what you will be receiving. Part 4655 does not need the duct mounting plate IF you choose to mount it on your ductwork. It can be wall or duct mounted.

The manufacturer is sometimes referred to as April Aire, Aprilair, April Air but is correctly spelled Aprilaire.