Aprilaire 4740 Relay 326010-701 Universal Compatibility: Industry-standard 3

Universal Compatibility: Industry-standard 3

meaning the branch line pneumatic signal increases in direct proportion to the sensed increase in ambient temperature

Rated for a maximum operating pressure of 250 PSI and temperatures up to 400°F

This unit is specifically rated for 220V AC

Aprilaire 4740 Relay 326010-701 Universal Compatibility: Industry-standard 3The Aprilaire 4740 Relay is a critical replacement component engineered specifically for Aprilaire 700 series humidifiers, including the 700A and 700M models manufactured after 2008. As a genuine AprilAire humidifier part, this fan relay is responsible for powering the circulator fan when the humidistat signals for moisture. Unlike older "Series One" versions that utilized the 4238 control board with an integrated transformer, this modern 24V