hqrp 2-pack wick filter compatible with vornado md1-0034 replacement ev100, ev200, evdc300, evdc500, evap2, evap40 evaporative humidifiers hqrp hqrp® 2-pack humidifier wick filter replacement. compatible with vornado md1-0034 replacement fits ev100, ev200, evdc300, evdc500, evap2, evap40 evaporative humidifiers. <p>for replacing the filter turn off and unplug the humidifier, remove the water tank, remove and discard used filter. install the new filter. make sure the filter fits flush against the bottom of the unit and snugs against the inlet grill. on the evap2 you may need to slightly bend the filter to match the curve of the unit. replace the water tank.</p>