I have a variable speed furnace and I keep the fan on constant. I have a power humidifier than is set up to kick on when the furnace calls for heat, and the humidistat calls for humidity. However, at this time of year, it is a little dry indoors, and warm enough during the day that the furnace is not running most of the day. Can I run the whole house humidifier with the furnace fan only? Or does the furnace need to be heating? I have a gas furnace, and humidifier is a honeywell 360 supplied by hot water. Thanks!