While technicians may temporarily depress the switch to observe system behavior

preventing mechanical stress or displacement during the ignition cycle

The "H" often denotes "Husky" or high-performance packaging depending on the distributor's cataloging

plenum-rated housing

Resideo HE300A1005 Humidifier While technicians may temporarily depressThe Resideo HE300A1005 is a professional grade fan powered humidifier engineered for high capacity moisture delivery in residential and light commercial applications. Part of the TrueEase humidifier line, this whole house evaporative humidifier delivers up to 18 gallons per day (GPD), making it the primary Resideo humidifier replacement for legacy units like the 32000429 001, P110 LFP1518, and 700M. It features a built in fan to pull air directly