Residential air conditioning is a complex subject with definite and consistent rules. There are two components that must be removed from the air. These are heat and moisture. They are of equal importance. One of the air conditioning rules is: The faster you run the blower, the more heat and less moisture you remove from the air. The slower you you run the blower, the more moisture and less heat you remove from the air. With a fixed-speed on/off, part-time blower, there is a definite limit to how slow you can run the blower.   The FanHandler gives you the best these two choices by covering them both.
cool 1When the air conditioner compressor first comes on, the FanHandler controlled blower is running at a slow speed. That catches the latent (humidity) load and really pulls moisture from the air. At the same time, the cold air conditioning coil reduces the temperature of the air going over it. This immediately increases the blowers speed and and sends the cool/dry air into your home. The speed of the blower stops increasing somewhere before it reaches full-speed. This is where it has found a balance between the humidity load and the heat load. The FanHandler controlled blower doesn't let go of the humidity load until it is down the drain and out of your home.  An interesting thing happens in Florida or any of the gulf states. When contractors install their first FanHandler, they get worried because the blower seems to be running too slow. The reason for this is that the FanHandler has found that the air is full of moisture and is busy helping the air conditioning system to remove it. When indoor relative humidity runs in the 75% range, there is a lot of moisture for the FanHandler to work on. When the contractor checks back the next day, the temperature of the air coming from the registers is cooler and moving faster and the indoor relative humidity is in the low 50% range.
cool 2cool 3It is disturbing to see the direction that the air conditioning industry is taking. Utility companies will kick-back a couple hundred dollars to the contractor or homeowner if they can save a little electricity. So, what is happening? The pressure is on the equipment manufacturers to speed up their blowers. Remember, the faster the blower speed the more heat and less humidity is removed from the air. (some water is always removed) The thermostat reacts to temperature. Remove the heat and the temperatures drop. The thermostat shuts off the air conditioner and blower before enough moisture is collected. So you save electricity. This is false economy because the homeowner has to set the thermostat to a lower temperature setting in the attempt to get rid of that hot muggy feeling. Because the thermostat is set lower, the air conditioner runs longer. Thus more electricity is used. The resulting lower temperature, combined with not enough humidity being removed, causes the home to feel cool and clammy. That moldy sock smell shows up about then.
cool 4The result is that speeding up the blower to ridiculous levels has produced what we consider is an unlivable situation. This might work in a laboratory setting, where nobody has to live all day. We don't think it works in the real world. PLUS, the high-speed blower strips moisture from the air conditioning coil and sends it down the ductwork. (mold?)
cool 5Here are facts that have not been taken into consideration. The slower the air moves across an air conditioning coil, the colder that coil is and the more moisture it collects. the faster that air moves across the coil the warmer it becomes and the less moisture it collects. The colder the coil's surface is, the better water will stick to it. The warmer the coil is, the less water will stick to it. Combine high air speed with a warm coil and you have water shooting down the ductwork. The FanHandler solves most of this problem by limiting the air flow until the moisture is removed from the air.


  • Mr. Peters,

    Hope this email finds you doing well. Just wanted to let you know that my Ecmmodulator is doing actually what I wanted it to do. Not sure if my HVAC contractor has installed anymore more units here in Birmingham area. Of course I believe the bread and butter for most HVAC contractors are new unit sales. Fyi, I’m planning on getting a new evap and condenser installed soon so I expect that upgrade will really improve the overall humidity level a little better in my house. Also, I’m thinking of getting another Ecmmodulator for my other unit and maybe two. As I like the benefit of the ecm motor running at a low speed to improve air quality. I’m not sure if you would sell to me or I have to contact that contractor again to handle the transaction. Anyways just thought I would touch base and thank you for all your help in the past with my project with Fanhandler.

    Merry Christmas