I'm trying to decide whether or not to install a whole house humidifier, and if so, how it should be done. I've gotten quotes from several contractors so far, but I have a couple of complicating factors in my home, so I'd like to hear thoughts from people in this forum.
I'm located in northern Ohio, and my home is about 1,800 square feet (1,400 is downstairs, including both bedrooms). The house is on a slab.
Last winter I used a portable room humidifier that can put out about 4 gallons per day. Except on very cold days (<15 degrees), it seems to keep the humidity at or above 30%. On really cold days, it might have dipped to 25%. That's why I'm looking for a central humidifier -- because this thing is barely adequate, plus it's only humidifying one area of the house and it's a pain to fill and clean frequently.
But here's the complicating factor. My furnace is in the garage, and it's very, very far from the master bedroom at the back of the house. Plus the master bedroom has exterior walls on three sides, coupled with huge windows and a set of French doors (which I cover with plastic, but they still contribute to heat loss). Needless to say, during winter nights, the bedroom's temperature can easily drop 10-15 degrees below the temperature at the thermostat.
(Side note: A year ago I had an HVAC contractor out to my house to give recommendations on how to correct the temperature difference between the master bedroom and the rest of the house. He came up with a couple possible solutions: 1) a system to divide the house into zones, which would be very expensive to retrofit given that the ducts are embedded in the slab; or 2) an electric baseboard heater controlled by a thermostat in the master bedroom. I've done neither, mostly because I'm probably not going to stay in the house for more than two more winters. I went to Target and bought a $40 oscillating heater with a thermostat control on it. Last winter I set the thermostat on the portable heater to 68 each night and closed the bedroom door, then I set the main house thermostat down to 56 to conserve energy in the rest of the house. This arrangement worked very well. Of course, I also had the portable humidifier in the bedroom while I was running the heater each night, so it kept the humidity in the bedroom high. But since my goal is to install a central humidifier and get rid of the porable humidifier, this is where I'm seeing a possible problem.)
I've had several HVAC contractors quote me on a whole house humidifier, and they're all recommending the Aprilaire 600. But when I've told them about my "problem" with the bedroom heat, and I ask what will happen to the humidity if I set the house thermostat to 56 each night and essentially heat the bedroom with the portable heater, I've gotten mixed answers.
One contractor said it'll be fine, because the 17 hours when the furnace will be running will get the humidity up to a decent level during the day. He said the humidity in the bedroom will drop at night, but it should still be at an acceptable level after 17 hours of humidity during the day.
Another one really didn't know what to say. He said running the portable humidifier the way I've been using it isn't a smart idea because of possible mold growth. But he didn't have a good answer when I asked what would happen if I install the Aprilaire 600 and continue to use the portable heater in the bedroom. He basically said, "It depends. You'll just have to try it out and see."
Any thoughts/opinions/suggestions for keeping my house effectively humidified without spending huge dollars? Or is there any more information you need before making suggestions?
(BTW, this seems like a great community. I did some lurking before signing up to make this first post, and there's a lot of fantastic information in here!)