Humidifiers and Dehumidifiers - First Time DIY for wiring a Humidifier

Hi all!

I am new to working with HVACs, but I decided to try wiring a new house humidifier into my HVAC system and I am looking for some guidance and advice. Here is what I have:

* Honeywell True Steam 9 Gallon Humidifier
* Trane 14XLi Air Compressor
* Trane 4TEE3F37 Air Handler
* Vision Pro IAQ T-stat (Came with humidifier)

I currently have an older Honeywell Thermostat that is wired. My house does not have any zones.

Here's several questions that I have been having and trying to research.

1. I am assuming I wire the Humidifier on the Return duct for the system

2. When I wire to the Furnace, I am assuming I will use the basic Vision Pro IAQ where I wire HUM 1 and 2 from the True Steam to the EIM. And then replace the existing Tstat wth basically the exact same wiring. I am assuming that the humidity controls will automatically pass through the existing wiring.

3. What other things should I consider before doing this project?

Thanks for your advice everyone!

* Trane 4TEE3F37 Air Handler
Do you know what model or size of the electric heater in the air handler?

1. I am assuming I wire the Humidifier on the Return duct for the system
?? Meaning mounting the humidifier itself on the return and putting steam in that duct?

2. When I wire to the Furnace, I am assuming I will use the basic Vision Pro IAQ where I wire HUM 1 and 2 from the True Steam to the EIM.
Correct.

And then replace the existing Tstat wth basically the exact same wiring. I am assuming that the humidity controls will automatically pass through the existing wiring.
Between the T-stat and EIM, you will only use 3 wires.

Rest of the wires from EIM to the air handler you may need to buy a new set of t-stat wire. The EIM takes care of everything else.


3. What other things should I consider before doing this project?
Did you get an outdoor sensor with your unit?

Jay --

Thanks for the response... Here's what I know (or don't know)!

The Air Handler is a Variable Speed 37,000 btu 3.0 ton unit. The heater is 15 kW. It was installed with the Trane XL14i about 3 years ago to my existing thermostat. Does that help identify the heater size?

As for mounting, I have a horizontal setup with an electronic air cleaner. I believe the horizontal direction is to the right. So I imagine I am mounting the humidifier to the right side of the air handler on the duct.

Okay, a bit confused on the wiring side. Wouldn't the existing unit have the wires from the EIM already to the existing Tstat? Since I am just replacing the Tstat with a new one (for humidity control), wouldn't it just be a matter of taking the old tstat off and putting the new one on with no additional wiring? The only wiring I was thinking I would need is from the Humidifier to the EIM at this point. I should state that I am assuming the trane system has an EIM on it. Is this correct?

As for an outdoor sensor, I am unsure yet if one came with the humidifier, as the humidifier is arriving on Saturday. I take it you are recommending to get one if it doesn't come with it?

The Air Handler is a Variable Speed 37,000 btu 3.0 ton unit. The heater is 15 kW. It was installed with the Trane XL14i about 3 years ago to my existing thermostat. Does that help identify the heater size?
15 kW is your heater size. Take a look where the t-stat wires up to in the air handler, see how the W's are hooked up, and let me know.

As for mounting, I have a horizontal setup with an electronic air cleaner. I believe the horizontal direction is to the right. So I imagine I am mounting the humidifier to the right side of the air handler on the duct.
The humidifier should be down stream of the EAC, (Supply side of the system)

Okay, a bit confused on the wiring side. Wouldn't the existing unit have the wires from the EIM already to the existing Tstat?
Right now, you just have a wire from the t-stat going right to the air handler.

With the new t-stat, there will be a control (EIM) in between the t-stat, and the air handler.

http://img297.imageshack.us/img297/5319/visionprola4.jpg
EIM (Equipment Interface Modular) on the right of the t-stat.

There are extra things on the control/EIM that I want you to take advantage of, and may not have enough wire in the bundle to do this.

No, the air handler does not have the EIM, just the standard control board.

As for an outdoor sensor, I am unsure yet if one came with the humidifier, as the humidifier is arriving on Saturday. I take it you are recommending to get one if it doesn't come with it?
I would, that way you can lock out the aux heat on mild days, and control the humidity level with having to go to the t-stat to adj the settings.

Okay.. I actually got the user manuals from Trane to help with the wiring and I also received the humidifier today.. CHEER!

So, I have more answers (and more questions) now.

1. YES, I have an outdoor sensor. I imagine I can trace my compressor wires to my outside unit to help place the outdoor sensor.
2. Having trouble locating the wiring from the tstat to the air handler. Total noob question... Do I need to take a panel off the air handler to find the furnace board?
3. From the heater side... the model number if BAYHTR1415, hoping this would give you an idea on sizing.

In addition, I pulled my existing thermostat (Honeywell CT3611) off and looked at the wiring and here is what it has:

R - Power
W2 - Auxiliary Heat Relay
E - Emergency Heat Relay
W1 and Y - tied together with a jumper (Compressor & Stage 1 Heat ?)
O - Changeover Relay
G - Fan Relay
C - Common

Based on our earlier discussion, it sounds like only 3 wires would eventually be used for the new thermostat.

2. Having trouble locating the wiring from the tstat to the air handler. Total noob question... Do I need to take a panel off the air handler to find the furnace board?
Yes, you need to take the panel off. TURN OFF power before you go diving into the air handler.

Inside, you'll see where the t-stat wire hooks up. R-W1.. ect..

While you are in there, Please look at the Dipswitch settings, and let me know what they are all set to.

Based on our earlier discussion, it sounds like only 3 wires would eventually be used for the new thermostat.
Correct,
T-stat---color---EIM
1------Red------1
2-----White-----2
3-----Blue-------3

Then wire to the air handler.

EIM-------color------AH------HP
R/rc/rh---red------R or T--------
O/B------orange----O-------
Aux------white-----W1
Aux2-----black-----W2/W3-----
Y---------yellow------Y
G---------green------G

---------
Humidity control...

Jumper from one of the R's down to DHM1

DHM3 to BK on Air Handler. (Remove Factory Jumper between R and BK)

Hum1----TrueSTEAM HUM
HUM2----TrueSTEAM HUM


Then here what I suggest for Installer set up menu. Anything that shows "E" change it to number value as I posted.

110-0

120 to 160 you can figure out.

172-2
174-1
176-2
190-0
200-0
220-2
240-3
250-3
280-1
300 to 330 up to you

342-1
345-2
346-0
350-0
360-40
370-1
372-3
374-1
379-1

390- Are you gone alot in the summer?

Rest you can figure out, let me know if you have questions.

Making progress....

Took the panel off and here is what we have:

Wiring panel is as follows:

G O B W3 W2 W1
R BK T Y Y/LO

There are jumpers on R-BK (factory) and a jumper on W3-W2.
There are no wires on BK, T, Y/LO, and W2.

From a dipswitch perspective, the switches are ON for 2, 5, 6, and 7.

And no.. I am home most of the summer. I live in PA.

In my AH, I had two sets of wiring panels. One right inside on the left side attached to the frame labeled LVTB, and then another smaller panel which was enclosed (I had to open it) that contained the wiring AND the dipswitches. Where do I wire the EIM too? The outside panel or the one in with the dipswitches?

Finally, I saw where you mentioned wiring DHM3 to BK. I am looking at the EIM and I do not have a DHM3 location. I only have DHM1 or DHM2. As I do not have a dehumidifier, should I worry about this or do I need to make a change?

Out of curiosity... know of any way to mount this on a fiberglass duct?

On my earlier post, I said R or T from EIM, wire only R ignore the T.

There are jumpers on R-BK (factory)
Remove that jumper and add a wire from EIM's DHUM2.

and a jumper on W3-W2.
That jumper stays, and wire this from Aux2, and should be a wire from the HP outside.


From a dipswitch perspective, the switches are ON for 2, 5, 6, and 7.
1 to 4, I don't know what's your A/C tonnage? (Model#?)

5 and 6, I am not able to find anything, look on back of the panel for dipswitch settings.. This should say something like Comfort-R or Enhanced mode.

7-On 8-Off, We are OK with this.



another smaller panel which was enclosed (I had to open it) that contained the wiring AND the dipswitches. Where do I wire the EIM too? The outside panel or the one in with the dipswitches?
You run a wire from EIM to this area where you are hooking up the t-stat wires.

Finally, I saw where you mentioned wiring DHM3 to BK. I am looking at the EIM and I do not have a DHM3 location. I only have DHM1 or DHM2. As I do not have a dehumidifier, should I worry about this or do I need to make a change?
My mistake, it should of say DHM2, not 3. Sorry.

Out of curiosity... know of any way to mount this on a fiberglass duct?
Mount the EIM on the side of the air handler, WATCH were you run the screw into to mount this on the unit.

Okay... not a lot of room to work with on mounting on the air handler, so I decided to try rigging something between the floor joists to hang a vertical metal sheet that would wrap the duct and provide stability for the humidifier.

In my conversations with one of the HVAC specialists at Home Depot... he was mentioning that the steam humidifiers on horizontal HVACS are not as effective as on vertical HVAC units. In addition, he mentioned some concerns with molding in fiberglass since the fiberglass duct interior is not insulated.

To be honest, it sounded fairly logical. I am thinking this may be a bad idea at this point. Thoughts?

Are you ducts the metal ones with fiberglasss inside?

Or

Flex duct with the silver coat?

Is your air handler in the attic or in the basement or crawl space?

Take a photo of yoru set up if you can.

Are you ducts the metal ones with fiberglasss inside?

Or

Flex duct with the silver coat?

Is your air handler in the attic or in the basement or crawl space?

Take a photo of yoru set up if you can.

No metal at all. Seems to be entirely fiberglass with the silver coat. I have flex-ducts coming off the main run, which seems to be brown plastic flexible hoses for the ducts around the house.

The HVAC unit is located in a crawlspace about 3 1/2 feet high in a horizontal mount placement.

I am planning on refinishing my garage into another room of the house, as my wife and i are having a second kid and need to get some extra room. Currently, the house is about 1750 sq feet, with the garage conversion, it will be about 2000 sq feet. I plan on running ducts into the garage space to link it to our central air.

As I was working down below, and I was debating about having the ducts replaced in the crawlspace as the flex-ducts didn't look all too great. There was a couple of places where the ducts looked to be at a 70 degree angle and I was thinking the airflow had to be pretty poor for those ducts.

You could hook up the steam humidifier to your duct, but you'll have to peel back the fiberglass, chances are you will have a plastic lining inside the duct, and you could do the steam, but you don't have a good spot to put the spout into the duct since it's not solid.

If the duct looks bad to your eyes, may not hurt to have someone come out and take a peek at it to be sure, or post a photo for me to see what you got going there.

You could hook up the steam humidifier to your duct, but you'll have to peel back the fiberglass, chances are you will have a plastic lining inside the duct, and you could do the steam, but you don't have a good spot to put the spout into the duct since it's not solid.

If the duct looks bad to your eyes, may not hurt to have someone come out and take a peek at it to be sure, or post a photo for me to see what you got going there.

I actually took one of the flex ducts off and peeked inside... no plastic lining either. I actually called a guy I golfed with in the past to come out and check it out. We'll see what he says.

Yeah, I would not suggest putting steam into the fiberglass lined duct..

let us know what he says.