We have installed a generalaire power hum. We are having a problem with getting the humidity up past 35% even with the humidistat cranked. The unit is mounted on the supply side of a high eff. furnace. The furnace is an upflow, but 90's back down through the floor into a crawl space. The return is under the floor in crawl space. This is the reason we opted for the power model,so we did not have to connect a bypass to the return under floor.(no room for 6" bypass.)
If anybody has any input that would be great.
35% humidity level is ALOT if it's really cold out. Read the literature that came with the unit. A compfortable humidity level depends on temperature (that's why it's called relative humidity). That being said, humidity level depends ALOT on house construction. Loose homes are dry in the winter and moist in the summer. The equipment can only add (or substract if central A/C)humidity so much. And do realize, that particular unit you installed ONLY adds moisture to the air when the furnace runs for heat. So, worst case, if the furnace is grossly oversized for the house, fan run time is little.