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Question: My furnace relay does not have "auxilliary" contacts. Can I connect the 500 to the fan contacts so the 500 goes on when the fan goes on?
Document: - I purchased a 4 ft section and was plenty for a vertical setup.18-2 thermostat wire (a few feet of 18-5 may be helpful to go between the humidifier and your furnace, but 18-2 will work there as well)HVAC foil duct tapeRubber weatherstripping to seal the 500 casing to the duct work.
I love the feature that can turn on the fan without turning on the furnace, which allows for the best control of humidity. It also does a great job lowering (not humidifying too much) the humidity on those really cold days so there is not condesation on the windows, which could eventually lead to mold.All in all, if you install this correctly and use all the features included, you won't be disappointed.
I wouldn't say it was the easiest thing to do, but it wasn't extremely difficult either. Took us about 2-4 hours, and that was taking our time and doing a very neat job. The only thing I haven't done yet is placing the temp probe outside (winter and lots of snow in MI), so I have it setup to only kick on when the furnace does, vs. thinking it is 65 deg. outside and running the fan and bumping the humidity too high to reach rel.
This was especially true for the two conductor wire to connect the outdoor probe and to connect the transformer to the unit. Plan to buy some wire locally if you buy this unit.Installation difficulty: If you are comfortable with tin snips, furnace control wiring and are able to add a transformer to a surface mounted electrical box this is not hard to install yourself. If not, plan on having a pro or good friend who is handy do the install.
One real plus of this controller is it can turn on your furnace fan to add humidity even when the furnace is not heating. It also has an outdoor sensor so it regulates the maximum humidity based on outdoor temperature so you don't get too humid and have condensation problems when the outdoor temperature is very cold. Keep this in mind if deciding to install yourself as you need to drill through the wall to place the probe outside and route wiring back to the controller.
;)Cons:- I'm a very skilled workman and the install took longer than expected. Look at spending about 6 hours installing this product.- The transformer that was shipped with the product was DOA. No 24VAC out. Luckily I had a spare sitting around.Pulled this off a review from the 600 model. Revised/Added a couple of items. It works for the 500 model as well.
The item is light and well packed and very basic so no complaints there.I have a 1,500 sq/ft house and it does a fine job so that I don't shock the hell out of my cats and the lining of my nose feels non-dry again. The house is not air tight and some of the tall windows next to the sliders are popped so it is good that it still works well on setting 6.
Was trying to decide between the 500 and 600 models. They are basically the same, besides how much humidity they can add to the air. My home is about 3300 sq feet, and the 500 is rated for 3000 sq. feet. Another review stated the manufacture said that with a tight home you can bump up the rating by about 30%. Went with the 500 and I have no regrets. Install wasn't hard and wasn't easy either.
It doesn't show how high it goes into the duct because of a poor image shown. I used a clear tube as others have suggested from the humidifier to the PVC drain tube so that I can make sure it's working without having to lean down near the drain to hear the trickle of water. I've never worked with hard copper lines, easy to strip but then easy to snap off too.
Because I'm a DIYer and installed it, there's no warranty, if a contractor installs it, it has a 5 year warranty, but for less than $150.00 versus $300-500 purchased and installed by a contractor that works for me. The weather since installation has been between 40 degrees and -12 below and the automatic digital control adjusts to keep the %RH perfect for the conditions.
Answer: No, the fan motor is 120VAC and the humidifier controller and water valve are 24VAC.  You will damage them.  Without knowing exactly what you have it is hard to tell you how to hook this up.  The 500 control box has terminals that will match your home thermostat terminals and your furnace terminals. Terminal R-is red wire, Terminal W is a white wire.  Terminal G is a green wire.  And terminal Y is a yellow wire.  Match the terminals from your thermostat or furnace with your Aprilaire controller.  the wire can be purchased on line or from your local building supply like Home Depot.  Both the Aprilaire humidifier and the controller come with wiring instructions.  However if you have a late model high efficiency furnace it will have a humidity terminal marked HUM.  If this is the case connect the Aprilaire controller G terminal to the humidity terminal.  No other wires should be on the Aprilaire controller G terminal or the HUM terminal of the furnace.  If you connect it incorrectly you do run the risk of damaging the controller, your furnace or both.  I have 30 years experience in control circuits that helped me hook this up.  Better to ask a professional for help if you have any confusion.Followup after I looked at my furnace connections.I made one mistake for the HUM terminal on high efficiency furnaces.  You need to connect W terminal of humidity controller to HUM of furnace not G.  FYI on furnace connectionsR is power out to thermostat and controllerY is demand for cooling input to furnaceW is demand for heat input to furnaceG is run fan with no demand or heat or cooling input to furnaceC is return for power and is required for humidity controller to provide power return path.  It is also used on high end thermostats that require power.Normal thermostat wire is 4 conductor for newer thermostats you may need the C connection.  Home Depot has 5 conductor wire.