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List Price: $399.00
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Spent many hours researching how to install a whole house humidifier and this one was recommended many times. When our furnace got serviced this fall the technician also recommended we get a humidifier and when I asked him which model this is the one he recommended. It's really hard to find anyone selling this unit because the manufacturer doesn't want just anyone to install it, they recommend a technician so I was pretty happy when I found it here on Amazon.
After doing some research and a couple times watching this video on youtube() I decided to take the project on myself. It actually was a lot easier than I had expected. Aprilaire's instructions were pretty easy to follow and the automatic digital control gives you a great display in case an error code comes up.
If you are good at following instructions, and have some confidence you can save yourself around $300-$500 on the installation cost I was quoted from 4 different HVAC companies. I was able to complete the project in 3 hours. Another friend of mine installed the same unit in his house and he took just about the same amount of time, he might have been closer to 4 hours. So in 3-4 hours you will be sitting back enjoying the new humidifier.
Things You Will Need To Install Yourself:
* 3/4" PVC pipe (optional, i used it to run the 1/2" tubing into to continue to the drain instead of running the tubing all the way, I split into the same 3/4" coming out of the furnace)
* 1/4" copper tubing to run the hot water into the humidifier
* 1/2" plastic tubing to drain the water
* Sawzall or equivalent tool to cut sheet metal
* Low-Voltage wiring to wire the thermostat and thermometer (i bought 2 of these Coleman Cable 09631 CL2 Bulk Thermostat Cable, 18-Gauge 2-Conductor 50-Feet)
* 2 Electrical Terminals for the wiring
* Some wiring caps (medium size)
* Foil Tape (I bought 3M 3311-50 Scotch Foil Tape, 2-Inch-by-50-Yard)
* Pipe Cutter (I bought Ridgid 40617 1/4-Inch to 1-1/8-Inch Close Quarters Tubing Cutter)
* Permanent marker
* Level
It's been running for over a month now and I was able to notice a difference immediately. I even have a gauge on the second floor that measures humidity and it's constantly has the correct amount of humidity in the house. I'm very happy with this purchase and highly recommend it to anyone in the market.
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I had been researching whole house humidifiers for some time and finally decided on this Aprilaire Model 700 Automatic Whole-house Powered Humidifier with Digital Control from talking to local HVAC installers and reviews I located online. I checked around and the lowest I could find someone to install it for me was $350, so I decided to take the plunge and do it myself. I was a little apprehensive because I had never worked with a furnace or cutting into sheet metal before. I bought an inexpensive pair of sheet metal snippers and it was a little difficult, but not bad overall to cut the hole in the plenum. Home Depot proved to be invaluable in helping me with the plumbing connections. I used shark-bite fittings instead of the supplied saddle valve (every plumber I talked to advised me against using the saddle valve). I also used plastic pipe instead of copper. Overall I spent about $70 on supplies. I installed the unit on the supply side, as was recommended, but I could not justify hooking it into the hot water line and watch energy just pour down the drain. The instructions indicated a cold water supply was fine as long as the unit was mounted on the supply side. The unit does trickle water down the drain hose as it is operating, this is normal. My biggest apprehension was the wiring. I found some VERY helpful youtube videos of an HVAC installer somewhere in the midwest installing one of these in a clients home. I probably watched them 20 times during my own installation. One hiccup I encountered was after wiring everything according to the instructions, my unit powered on fine, but would come on when there was a call for heat, instead of waiting for the blower to come on. This made me extremely nervous as I didn't want water vapor blowing into the plenum before the blower was operating. A quick email to the youtube video publisher mentioned earlier confirmed my worry and he explained to wire the transformer into the HUM terminal neutral on the furnace board and to then use the power for the blower HEAT terminal for the power. The installation instructions made no mention of what is correct as to when the humidifer should come on, but for peace of mind, wiring as suggested by the HVAC installer was preferred. One additional step I took was to purchase some duct sealant that I then used to calk around the unit to seal off any gaps. I have already noticed a huge difference in the humidity level in our home, as we live in a very dry climate in SE Idaho. I was tired of spending money upon money buying table top humidifiers that required expensive filters or just broke down and were junk after a couple of years. This unit seems like it will meet my needs, I give it 5 stars and would encourage someone with general handy-man skills to go ahead and try installing, but to be prepared to ask questions if you get stuck.
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I have installed the Aprilaire Model 700 a couple of months ago. It is working properly with a couple of adjustments. I made the connection for automatic setting (with a exterior temperature sensor).
When I received the humidifier I notice the "NEW IMPROVED WIRING DIAGRAM" (see picture). If you follow the wiring diagram, the humidifier will start working when there is a call for heat (connection "G").
The is a problem caused by the following: (1) my furnace fan wait for 1 minute -after the heat callto start running. But, the humidifier is already on and is blowing humidity into the system. (2) My basement is unfinished, and the humidity inside the returning duct goes down rather significantly (e.g. if the house's relative humidity (RH) is 40%, the returning duct might be 30%), yet once the furnace fan start running the RH stabilizes at the RH of the house. These two factor may create a very short run of the humidifier.
I read all the reviews, and one solution is to wire into the furnace control card. I found this rather difficult because I couldn't find the furnace' card (it is a Lennox) specifications. So, the solution I found is to install a DELAY ON MAKE (Timer with .03-10 minute adjustable delay and 6" wire leads, universal 18-240 VAC: you can get this timer in Amazon as well for a $15 aprox.) to install between the humidistat outputs (the second "H" connection) and one of the solenoid line (see picture and modified wiring diagram). I adjusted the time to 3 minutes, so the RH inside the duct system can stabilize before calling for humidity.
Since then, the humidifier does not blow air into the system when the furnace fan is not running, and also wait long enough to allow the RH inside the duct to stabilize.
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Buyers Beware.
In the lower right-hand corner of the installer instruction sheet for the 700 & 700m is this note:
"The Model 700 is not suitable for installation on ducts with horizontal airflow. Performance will be reduced." This is an understatement; performance is horrible when mounted on a horizontal duct.
It appears that many HVAC dealers aren't aware of this limitation, and happily recommend it as "top-of-the-line." When installed horizontally, the Model 700's hardly work at all--even with hot water supplied--and the dealer flounders around scratching his *** while you suffer from dry eyes, cracked skin, and static charges around the house.
There's a fascinating thread on this topic on the Professional HVAC forum. Just google "aprilaire 700 horizontal duct."
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Great product, but can a lot of water passes through the unit which is wasteful and costly because it's hot water. I highly recommend NOT using the standard A35 Water Pad, but one of the more efficient "wick" type filters rated at 50% greater capacity. Several companies offer compatible products such as the Aprilaire A35-W Wick Water Panel, A35WPR Aprilaire 600 Humidifier Water Panel Paper Evaporator, or RPS BestAir A35W White Pad RPS #A35W Aprilaire350 Water Pad, or Honeywell ME360, HE360B or Clenair Ultra Upgrade Humidifier Panel model CA35UP. These are all hybrid pads made out of materials (usually paper fiber) that retain more moisture available for evaporation compared to the standard A-35 water panel where water quickly drips off. Another mitigation to this problem is to adjust the valve on the hot water intake line so that surplus water flowing through the unit is minimized. My professional installer could not get the drain line to go into the plumbing drain, so the drain water goes into the Air Conditioner condensation drain line. He told me there's a risk with that type of installation that the drain water line can freeze or create ice buildup outside the house at the drain point. It's preferable if the drain can go to existing plumbing drain rather than AC line, which could freeze if used in winter, but this may not always be convenient with your building layout. Also I recommend not depending on the filter change reminder light on the control panel since it's just a dumb timer. The length of replacement time will depend greatly on actual mineral buildup, i.e. how hard your water is, how often the unit runs, and how much water passes through it.
