Aprilaire 700 Wiring Questions
#1
01-04-11, 09:43 PM
Aprilaire 700 Wiring Questions
Okay, so I'm new to HVAC wiring and really don't know where to go from here. I have an Aprilaire 700 humidifier and an American Standard model TWG025A140B1. I can handle the installation up to the point of the wiring. I've been trying to figure out what I have in the furnace from this wiring diagram:
From that, I see that I already have a 240V to 24V transformer (technically 230V to 21V; I don't know if that matters), which is on the left in this picture:
What I'm thinking is that I could use the low voltage red and blue lines coming out of that transformer for the R and C humidistat terminals. Is this correct?
The other mystery is what to wire the W/G and Cf terminals to. The diagram shows a "low voltage field connection" with lots of low-voltage wires available, and two of them (white) seem to be unused, terminating into a wire nut in this picture:
Perhaps these would be useful in some way, maybe for the W/G and Cf terminals?
Please help; I'm really at a loss and (obviously) in over my head here, but would love to be able to do this myself.
From that, I see that I already have a 240V to 24V transformer (technically 230V to 21V; I don't know if that matters), which is on the left in this picture:
What I'm thinking is that I could use the low voltage red and blue lines coming out of that transformer for the R and C humidistat terminals. Is this correct?
The other mystery is what to wire the W/G and Cf terminals to. The diagram shows a "low voltage field connection" with lots of low-voltage wires available, and two of them (white) seem to be unused, terminating into a wire nut in this picture:
Perhaps these would be useful in some way, maybe for the W/G and Cf terminals?
Please help; I'm really at a loss and (obviously) in over my head here, but would love to be able to do this myself.
#7
01-05-11, 08:33 PM
You're right, of course. It's the 60, and the wiring instructions that came with the humidifier must be for the 58. The wiring instructions in the little booklet with the humidistat are completely different, and this is the first time I'm seeing them. So, I'm even more lost than I was before.
So, now the R and C humdistat terminals get wired to R and C "on the furnace terminal strip." Problem is, I don't see where my furnace terminal strip might be. What you see in the pics above is all I got. Along with this monstrosity:
If I could find this terminal strip, I'd be golden. But I don't see one, and I don't know what the R, C, G, Y, and W terminals might correspond to.
And I don't know where to wire up the transformer to connect it to the two H terminals on the humidistat, or if I even need the transformer, given that I seem to already have one (in the pics from my first post).
Whew, this is confusing.
So, now the R and C humdistat terminals get wired to R and C "on the furnace terminal strip." Problem is, I don't see where my furnace terminal strip might be. What you see in the pics above is all I got. Along with this monstrosity:
If I could find this terminal strip, I'd be golden. But I don't see one, and I don't know what the R, C, G, Y, and W terminals might correspond to.
And I don't know where to wire up the transformer to connect it to the two H terminals on the humidistat, or if I even need the transformer, given that I seem to already have one (in the pics from my first post).
Whew, this is confusing.
#8
01-05-11, 08:46 PM
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Ok, The wires will be the wires are wire nut up together since air handler don't ahve a board like a furnace.
so, this where you join the wire nut.
Humidistat--------wire from air handler itself.
R-------------------red
C-------------------blue
W------------------green
Are you going to hook up the hard wired transformer for the humidifer/H side?
so, this where you join the wire nut.
Humidistat--------wire from air handler itself.
R-------------------red
C-------------------blue
W------------------green
Are you going to hook up the hard wired transformer for the humidifer/H side?
#9
01-05-11, 09:21 PM
Originally Posted by Jay11J
Ok, The wires will be the wires are wire nut up together since air handler don't ahve a board like a furnace.
R-------------------red
C-------------------blue
W------------------green
R-------------------red
C-------------------blue
W------------------green
Originally Posted by Jay11J
Humidistat--------wire from air handler itself.
Originally Posted by Jay11J
Are you going to hook up the hard wired transformer for the humidifer/H side?
And where would the Gf terminal get wired to? It's supposed to go to the G terminal on a furnace terminal strip, but since I don't have a strip....
#10
01-06-11, 09:43 PM
Just a thought... due to the limited space available on the supply, my plan is to put this thing on the return. Would I be better off with a bypass like the Aprilaire 600 in this situation? I'd rather know the hard truth now while I could still do something about it than after I cut the hole for the 700.
You can see what I'm dealing with in this pic:
You can see what I'm dealing with in this pic:
#12
01-07-11, 05:23 AM
Member
you could use a 600, or the 700 on the return. The 700 on the return would most likely need a trap to keep the water from being pulled back in to the humidifier and that in turn usually causes leaks.
you can use the transformer in the AH, however, I don't recommend it. A better solution would be to find a nearby 120v power source to power the X-fmr.
GF will connect with the green wire that will be wired with W
Well, that's the thing. I'm not sure if I need to hook up the transformer that came with the humidifier (120V to 24V), since I already have the 240V to 24V transformer in the air handler. Should I find a nearby 120V source and use the transformer that came with it, or can I somehow branch off from the 24V wires from the transformer already in the air handler?
And where would the Gf terminal get wired to? It's supposed to go to the G terminal on a furnace terminal strip, but since I don't have a strip....
