Whole House Humidifier

Basement, Blog, Home / Wednesday, December 19th, 2018

I have dry, itchy skin. My wife has dry, itchy skin. Our dog has dry, itchy skin. Our cat, well she’s the odd one out.

Every winter it is the same. I get really dry and really itchy. We also get static shocks just looking at each other, or maybe we just still have that spark in our relationship. Ellie thinks it’s the dry air in the house so I had to do something about it, just to see if she’s wrong and it really is that spark in our relationship. So I went out and bought a whole house humidifier to add onto our furnace. 

The internet said I should be able to install one of these in a couple hours, so how hard could it be for a novice like me? Plus, having some more humidity in the house can benefit Ellie’s houseplant obsession. Those little plants need the best atmosphere they can get!

humidifier honeywell

What I bought was a Honeywell HE240A because it’s what the local home goods store had in stock and it fit the size of our house. Set me back $133.50 and it came with absolutely everything I needed to install it on our furnace. Not a bad deal if it gets rid of the itchiness for years to come. We spend that on lotion every year, it seems.

humidifier furnace start

The first step to installing the humidifier was to figure out where to put it. Because of how the housing for it is set up, we were a bit limited. There is a vent right above the furnace that does a good job leaking hot air into the basement where were don’t hang out and I was really hoping I’d be able to make the hole a bit bigger and jam the humidifier in there to seal it up. However, the gas line for the furnace gets in the way of the humidifier and I figured it’d be easier to deal with that vent another time that learn how to move a gas line. Stay tuned for next week’s blog where I try and fail and talk about insurance claims and house shopping! Just kidding.

I settled on installing the humidifier on the cold air return and then having the bypass duct connect to the supply line. This is an allowed setup, but the instructions make it sound like they would really prefer you install it on the supply. There is a great note that totally doesn’t confuse a later step that states I can simply swap “supply line” and “return duct” in the instructions if I want to install on the return duct. Easy enough, for now.

After I figured out where everything was going to go, I needed to start cutting holes and mounting everything. Let me tell you, cutting holes into metal is yet another one of those terrifying things I had to grin and bear to improve the quality of my home. If I screwed something up, I’d have to call in a professional to fix my mistake because I have no idea how to replace the duct work for my furnace and I’m sure the call would go something like this, “Our furnace isn’t heating our house anymore. We can hear it turning on and all, but I went down to check and there seems to be a big hole in the metal parts coming out of the furnace. Is that normal?” 

Cutting through the duct is actually fairly easy with some tin snips. I just need to drill some pilot holes to get the snips in and started and then it cut like butter. I’m surprised my cheap drill bits were able to get through the metal with ease too. I was suspicious, but I let it happen because I wasn’t looking for it to be more difficult than it wanted to be.

Once the hole was cut for the humidifier, I bent back the edges nicely so I wouldn’t cut myself. It was an unneeded step, but it makes it look like a professional job to me. Then mounted the body piece into the hole and secured it with sheet metal screws. I think one of the longest tasks for this hole project was finding the drill bit I had that would hold a screw steady so I could hold the screw while I tried to screw it in and secure the body piece. Turns out, the bit I needed was in the place I usually leave it, I just forgot where that was for a while. I really need to get better at putting all my tools back in their place once I’m done with them.

humidifier bypass duct hole cut

Next, I needed to cut a circular hole for the bypass duct. This was a bit trickier because straight lines are easy and curves are hard. The instructions recommended that I cut in a spiral motion and creep up on the line but that only worked about half way. In retrospect, I wish I would have cut about an inch from the line and then cut tabs into the remaining inch so I could bend those back and reinforce the hole with it. Also, I wouldn’t have so many razor sharp, jagged edges. Or maybe I would have given my hole saw a go at it, though I’m not sure that has the oomph needed to cut through metal.

humidifier bypass detail

Once the hole was cut, I had to insert the bypass duct and bend its tabs around the hole I just cut for it. If I had cut the hole better, it would have been easier. It got to be good enough, and then I further secured it with foil tape. Even though it looks messy with the tape on there, it sure cleaned up the mess that was there before. The other end of the duct was attached to the humidifier body using a large cable tie and then finished off with more of the foil tape. Nice and secure, and not a leak in sight (though the flexible duct that came with the kit could easily be punctured).

Next was yet another hole needed. This time it was for the pressure valve which lets the humidifier know when the furnace is blowing. I’m guessing when the air is blowing past the valve (it’s really just a tub stuck into the duct) it creates low pressure on the valve and that switches on the humidifier. For this, I needed to drill a 3/4″ hole for the rubber grommet to fit into. I didn’t have a 3/4″ drill bit, but I had an old spade bit I nearly destroyed that was supposed to be 3/4″ so I thought I could give that a try. It was warped, but somehow it managed to cut through the sheet metal. I popped in the grommet and then put the “valve” in. The other end of the valve tube I ran back to the humidifier body.

humidifier pressure valve

Before reading the instructions and watching videos on how to install a humidifier, the one piece of this puzzle that eluded me on how I was going to do it with my limited skill set was the plumbing aspect of it. I figured I’d have to cut the pipe and put in a new valve and run a water line to the humidifier. It turns out, it’s not that hard at all. Instead, the kit comes with what’s called a saddle valve and it clamps around a pipe and then you twist the valve to puncture it and you open it up by backing out the valve. That was a whole lot easier than I expected it to be. Once I knew what it was and how it worked, I started to see others in the basement. There was a line being run up to the refrigerator for the water and ice and then there was another I saw on one of the galvanized pipes but it wasn’t hooked up to anything. I had half a mind to use that one but it must have had a slow leak over the years and the calcium buildup made it unusable. Either way, it didn’t change how easy it was to run the water line.

humidifier saddle valve

As I was about to start cutting the final hole in the duct, I read something on the template that put the whole project on hold until I could get an answer I was happy with. So, remember how I was told to sway “supply line” with “return duct” because of where I was mounting the humidifier? Well, on the template for the humidistat, it states the humidistat must be mounted on the return duct. But I’m supposed to swap that, right? Okay, but it says must and that has to be important. I asked Ellie what she thought but she didn’t know and suggested I call support. So I did and sat on hold for over a half hour before I got an answer, even though when I got into the queue, it said there were only two people in front of me. 

humidifier wiring

While I was on hold, I decided to work on the electrical pieces. Which, after the humidstat, the electrical work was the last thing I needed to do before I could turn it all on. The wiring was simple enough, especially after some of the weird combos I’ve had to deal with while rewiring for the basement. Two wires go to the transformer, one of those wires plugs into the humidifier and the other gets tied together with a wire on the humidistat. The other wire from the humidistat goes into the humidifier. It was all very easy.

And then I got off hold and got my answer and basically the woman who helped me out said it didn’t matter where the humidistat was connected to the duct as long as it was. I’ll be honest, I didn’t like that answer because it didn’t feel right at first. I thought about it long and hard before decided I would, in fact, mount the humidistat on the return duct a couple feet before the humidifier. My reasoning is that it would be the best way to gauge the amount of humidity in the house by getting a reading from the air coming back into the system. 

Anyway, I cut the hole for the humidistat. This time, since the hole was a lot smaller, I used the 3/4″ spade bit for the corners of it and then cut the straight edges with the tin snips. I also had to drill out holes for the mounting screws and I made sure to do that before I cut the bigger hole, just so I’d have a sturdier surface to drill through. I popped the humidistat into place and called it a day.

humidifier drain tubing

It was finally the moment of truth where I would get to turn the whole system on. I turned on the power, set the humidistat to the “on” setting, and then turned on the water. That’s right about when water started pouring out of the bottom of the humidifier. So I quickly shut off the water to investigate. I’m not certain, but what I think happened was that I forgot to open the baffle for the bypass duct. So all this water was being pumped in but the vacuum didn’t exist to get it into the system. I’ve been monitoring it since I’ve gotten it up and running and so far I haven’t seen any other instances of leaking.

humidifier bypass in place

We’re less than a week into having the humidifier but so far I am noticing a difference. The house feels a bit warmer. And I feel a bit less dry. We’ll see how everything holds up as the winter gets into full swing, but I’m excited to put it through the paces because I think we’ll be a bit more comfortable.

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