Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.

thanks,

Nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

Nate Nagel wrote:

Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets so
dry indoors when it is cold out that it's calling for it to run near
continuously. This means that when the fan is running but the furnace
isn't firing, there's still water flowing through the humidifier which
is likely mostly going down the drain rather than into the air. I'd
rather fix it so that it only runs when the furnace is actually firing
so most of the water gets into the air and then it shuts off when it
goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

I have an Aprilaire hooked up to my furnace also, but it only comes on
when heat calls, not when the fan is running by itself. I just checked
the wiring on my furnace and the humidifier is hooked up to the W and
C terminals on the circuit board, so you can check if thats correct on
your furnace. You might have your humidifier wired up wrong and thats
why it comes on even if you only have the fan running.

Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets so
dry indoors when it is cold out that it's calling for it to run near
continuously. This means that when the fan is running but the furnace
isn't firing, there's still water flowing through the humidifier which
is likely mostly going down the drain rather than into the air. I'd
rather fix it so that it only runs when the furnace is actually firing
so most of the water gets into the air and then it shuts off when it
goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate


Follow up: I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. So I
figured that it must be controlled by cutting power to the receptacle
that it's plugged into. Unplugged it, powered furnace back up, 120V at
receptacle. Waited for heating cycle to finish. 0V at receptacle
(which is mounted on the outside of the furnace) OK, so there's a relay
inside there that is cutting the 120V to the humidifier to shut it off.
Powered furnace back down again, opened up control box. I see that
there is a "HUM" terminal but nothing is connected to it. There is a
pair of black and white THHN entering the area the white is connected to
neutral and the black is connected to "EAC." Not sure what that stands
for - but I suspect that that is somehow controlling the humidifier
because it's obviously field wiring (looped 14AWG rather than a stranded
wire with a factory crimped end.) I can't see where it goes, but am I
on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? I'd check 'em myself but it's kinda hard to keep
my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. It's pretty hard to
pull the cover on the recep box too, once it's warm I really need to
relocate a lot of this stuff to make it more user friendly (one screw is
partially blocked by a drain line, etc.)

thanks

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

Nate Nagel wrote:
Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom
gets as
cold as 62 degrees when the downstairs, where the thermostat is
located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it
myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets
so dry indoors when it is cold out that it's calling for it to run
near continuously. This means that when the fan is running but the
furnace isn't firing, there's still water flowing through the
humidifier which is likely mostly going down the drain rather than
into the air. I'd rather fix it so that it only runs when the furnace
is actually firing so most of the water gets into the air and then it
shuts off when it goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate


Follow up: I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. So I
figured that it must be controlled by cutting power to the receptacle
that it's plugged into. Unplugged it, powered furnace back up, 120V at
receptacle. Waited for heating cycle to finish. 0V at receptacle
(which is mounted on the outside of the furnace) OK, so there's a relay
inside there that is cutting the 120V to the humidifier to shut it off.
Powered furnace back down again, opened up control box. I see that
there is a "HUM" terminal but nothing is connected to it. There is a
pair of black and white THHN entering the area the white is connected to
neutral and the black is connected to "EAC." Not sure what that stands
for - but I suspect that that is somehow controlling the humidifier
because it's obviously field wiring (looped 14AWG rather than a stranded
wire with a factory crimped end.) I can't see where it goes, but am I
on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? I'd check 'em myself but it's kinda hard to keep
my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. It's pretty hard to
pull the cover on the recep box too, once it's warm I really need to
relocate a lot of this stuff to make it more user friendly (one screw is
partially blocked by a drain line, etc.)

thanks

nate


More info...

I took the humidifier apart to check it out... has its own internal
24VAC transformer, but the blower motor is 120VAC. Also, after much web
searching, it appears that "EAC" is usually 120VAC and does in fact go
hot when the blower is active, "HUM" is usually 24V and goes hot only
when there is a heat call. I guess I still need to verify this with a
meter on my particular furnace because neither the board nor the wiring
diagram pasted on the inside cover explicitly states. Unfortunately
Ruud's web site seems to be completely down otherwise I'd just look for
install docs... (the "owner's manual" that the PO's left us is useless)
I assume that "common" is a common neutral for everything 120 or 24?

Am I mostly correct so far?

So... it would seem that the easiest way to make this work is to ditch
the wires coming from "EAC" and "COM" which presumably run straight to
the recep for the humidifier, wire that recep always hot, then run a
pair from "HUM" and "COM" to a 24VAC ice cube/PAM/whatever and intercept
one of the legs from the humidistat? Actually I wouldn't even
theoretically have to rewire the recep if I'm understanding this
correctly, but I like to keep things clean and easily understandable so
nobody looks at my work and goes "what the hell was he thinking?" Also
that would make it neater if I were to have to replace the humidistat
down the road because if I understand it correctly the newer electronic
ones need a constant 24V (which I assume I could pick off of the xformer
built into the humidifier) and like to be powered up all the time not
just when the air handler is running.

Is there some handy online magic decoder ring for all the terminal
designations for HVAC stuff, e.g. furnace control board, thermostat, and
humidistat? I've DL'd all the manuals I can for equip. that I have but
it seems that there is a basic assumption that one knows what all those
letters stand for and while I'm relatively handy and (I'd like to think)
intelligent, I don't have much (OK, any) experience with HVAC. What the
heck does "EAC" mean, anyway? (I'm sure that I'll smack my forehead
when someone tells me, but it's not coming to me right now.)

If you've read this so far, I greatly appreciate any insight Wow, I
apologize for how long this has become... only explanation I can offer
is when I start to get into a project, I really get into it until I
understand exactly what I have to do.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Jan 2, 8:31*pm, Nate Nagel wrote:
Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. *Currently the humidifier is enabled
whenever the fan is running. *I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. *Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. *This allows the humidifier to operate when there is no
heat call. *What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.

While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets so
dry indoors when it is cold out that it's calling for it to run near
continuously. *This means that when the fan is running but the furnace
isn't firing, there's still water flowing through the humidifier which
is likely mostly going down the drain rather than into the air. *I'd
rather fix it so that it only runs when the furnace is actually firing
so most of the water gets into the air and then it shuts off when it
goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate

Follow up: *I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. *So I
figured that it must be controlled by cutting power to the receptacle
that it's plugged into. *Unplugged it, powered furnace back up, 120V at
receptacle. *Waited for heating cycle to finish. *0V at receptacle
(which is mounted on the outside of the furnace) *OK, so there's a relay
inside there that is cutting the 120V to the humidifier to shut it off.
* Powered furnace back down again, opened up control box. *I see that
there is a "HUM" terminal but nothing is connected to it. *There is a
pair of black and white THHN entering the area the white is connected to
neutral and the black is connected to "EAC." *Not sure what that stands
for - but I suspect that that is somehow controlling the humidifier
because it's obviously field wiring (looped 14AWG rather than a stranded
wire with a factory crimped end.) *I can't see where it goes, but am I
on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? *I'd check 'em myself but it's kinda hard to keep
my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs *I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. *It's pretty hard to
pull the cover on the recep box too, once it's warm I really need to
relocate a lot of this stuff to make it more user friendly (one screw is
partially blocked by a drain line, etc.)

thanks

nate

--
replace "roosters" with "cox" to reply.http://members.cox.net/njnagel- Hide quoted text -

- Show quoted text -
Since you have a voltmeter, you chould be able to poke around and find
some point that is only energized when the gas valve is energized.
That may be the primary of the transformer that feeds the gas vavle.
If the thermostat and other controls are all on the 24V side of the
trransformer, you are SOL unless you want to buy a transformer and
wire it backwards to develop 120 V from some point in the 24V control
circuit. Can't you throttle down the water flow slow not so much goes
down the drain on a continual basis?

Nate Nagel wrote:
Nate Nagel wrote:
Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is
enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my
house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom
gets as
cold as 62 degrees when the downstairs, where the thermostat is
located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it
myself,
but I figured I'd throw this out there in case there were any
"gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets
so dry indoors when it is cold out that it's calling for it to run
near continuously. This means that when the fan is running but the
furnace isn't firing, there's still water flowing through the
humidifier which is likely mostly going down the drain rather than
into the air. I'd rather fix it so that it only runs when the
furnace is actually firing so most of the water gets into the air and
then it shuts off when it goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate


Follow up: I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. So
I figured that it must be controlled by cutting power to the
receptacle that it's plugged into. Unplugged it, powered furnace back
up, 120V at receptacle. Waited for heating cycle to finish. 0V at
receptacle (which is mounted on the outside of the furnace) OK, so
there's a relay inside there that is cutting the 120V to the
humidifier to shut it off. Powered furnace back down again, opened up
control box. I see that there is a "HUM" terminal but nothing is
connected to it. There is a pair of black and white THHN entering the
area the white is connected to neutral and the black is connected to
"EAC." Not sure what that stands for - but I suspect that that is
somehow controlling the humidifier because it's obviously field wiring
(looped 14AWG rather than a stranded wire with a factory crimped
end.) I can't see where it goes, but am I on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? I'd check 'em myself but it's kinda hard to
keep my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. It's pretty hard
to pull the cover on the recep box too, once it's warm I really need
to relocate a lot of this stuff to make it more user friendly (one
screw is partially blocked by a drain line, etc.)

thanks

nate


More info...

I took the humidifier apart to check it out... has its own internal
24VAC transformer, but the blower motor is 120VAC. Also, after much web
searching, it appears that "EAC" is usually 120VAC and does in fact go
hot when the blower is active, "HUM" is usually 24V and goes hot only
when there is a heat call. I guess I still need to verify this with a
meter on my particular furnace because neither the board nor the wiring
diagram pasted on the inside cover explicitly states. Unfortunately
Ruud's web site seems to be completely down otherwise I'd just look for
install docs... (the "owner's manual" that the PO's left us is useless)
I assume that "common" is a common neutral for everything 120 or 24?

Am I mostly correct so far?

So... it would seem that the easiest way to make this work is to ditch
the wires coming from "EAC" and "COM" which presumably run straight to
the recep for the humidifier, wire that recep always hot, then run a
pair from "HUM" and "COM" to a 24VAC ice cube/PAM/whatever and intercept
one of the legs from the humidistat? Actually I wouldn't even
theoretically have to rewire the recep if I'm understanding this
correctly, but I like to keep things clean and easily understandable so
nobody looks at my work and goes "what the hell was he thinking?" Also
that would make it neater if I were to have to replace the humidistat
down the road because if I understand it correctly the newer electronic
ones need a constant 24V (which I assume I could pick off of the xformer
built into the humidifier) and like to be powered up all the time not
just when the air handler is running.

Is there some handy online magic decoder ring for all the terminal
designations for HVAC stuff, e.g. furnace control board, thermostat, and
humidistat? I've DL'd all the manuals I can for equip. that I have but
it seems that there is a basic assumption that one knows what all those
letters stand for and while I'm relatively handy and (I'd like to think)
intelligent, I don't have much (OK, any) experience with HVAC. What the
heck does "EAC" mean, anyway? (I'm sure that I'll smack my forehead
when someone tells me, but it's not coming to me right now.)

If you've read this so far, I greatly appreciate any insight Wow, I
apologize for how long this has become... only explanation I can offer
is when I start to get into a project, I really get into it until I
understand exactly what I have to do.

nate


Forgot to mention, none of the above is really meant as a knock on the
original installer of this setup. When we moved into the house the HVAC
was heat only, no AC, and the thermostat was an old honeywell round
mercury thing. So there was no possiblity of running the fan without
the furnace being active. This whole situation is entirely caused by
our desire to have AC and a fancy electronic thermostat with all these
features... just trying to make it right, is all.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Jan 2, 8:21*pm, Mikepier wrote:
I have an Aprilaire hooked up to my furnace also, but it only comes on
when heat calls, not when the fan is running by itself. I just checked
the wiring on my furnace and the humidifier is hooked up to the W and
C terminals on the circuit board, so you can check if thats correct on
your furnace. You might have your humidifier wired up wrong and thats
why it comes on even if you only have the fan running.

My partucular model has no blower, it's mounted outside the return
plenum and it's only the 24VAC that opertes it.
I was not aware there are 120VAC models with blowers, so I have a
totally different animal than you.

On Fri, 02 Jan 2009 23:21:44 -0500, Nate Nagel
wrote:

Nate Nagel wrote:
Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom
gets as
cold as 62 degrees when the downstairs, where the thermostat is
located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it
myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets
so dry indoors when it is cold out that it's calling for it to run
near continuously. This means that when the fan is running but the
furnace isn't firing, there's still water flowing through the
humidifier which is likely mostly going down the drain rather than
into the air. I'd rather fix it so that it only runs when the furnace
is actually firing so most of the water gets into the air and then it
shuts off when it goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate


Follow up: I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. So I
figured that it must be controlled by cutting power to the receptacle
that it's plugged into. Unplugged it, powered furnace back up, 120V at
receptacle. Waited for heating cycle to finish. 0V at receptacle
(which is mounted on the outside of the furnace) OK, so there's a relay
inside there that is cutting the 120V to the humidifier to shut it off.
Powered furnace back down again, opened up control box. I see that
there is a "HUM" terminal but nothing is connected to it. There is a
pair of black and white THHN entering the area the white is connected to
neutral and the black is connected to "EAC." Not sure what that stands
for - but I suspect that that is somehow controlling the humidifier
because it's obviously field wiring (looped 14AWG rather than a stranded
wire with a factory crimped end.) I can't see where it goes, but am I
on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? I'd check 'em myself but it's kinda hard to keep
my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. It's pretty hard to
pull the cover on the recep box too, once it's warm I really need to
relocate a lot of this stuff to make it more user friendly (one screw is
partially blocked by a drain line, etc.)

thanks

nate


More info...

I took the humidifier apart to check it out... has its own internal
24VAC transformer, but the blower motor is 120VAC. Also, after much web
searching, it appears that "EAC" is usually 120VAC and does in fact go
hot when the blower is active, "HUM" is usually 24V and goes hot only
when there is a heat call. I guess I still need to verify this with a
meter on my particular furnace because neither the board nor the wiring
diagram pasted on the inside cover explicitly states. Unfortunately
Ruud's web site seems to be completely down otherwise I'd just look for
install docs... (the "owner's manual" that the PO's left us is useless)
I assume that "common" is a common neutral for everything 120 or 24?

Am I mostly correct so far?

So... it would seem that the easiest way to make this work is to ditch
the wires coming from "EAC" and "COM" which presumably run straight to
the recep for the humidifier, wire that recep always hot, then run a
pair from "HUM" and "COM" to a 24VAC ice cube/PAM/whatever and intercept
one of the legs from the humidistat? Actually I wouldn't even
theoretically have to rewire the recep if I'm understanding this
correctly, but I like to keep things clean and easily understandable so
nobody looks at my work and goes "what the hell was he thinking?" Also
that would make it neater if I were to have to replace the humidistat
down the road because if I understand it correctly the newer electronic
ones need a constant 24V (which I assume I could pick off of the xformer
built into the humidifier) and like to be powered up all the time not
just when the air handler is running.

Is there some handy online magic decoder ring for all the terminal
designations for HVAC stuff, e.g. furnace control board, thermostat, and
humidistat? I've DL'd all the manuals I can for equip. that I have but
it seems that there is a basic assumption that one knows what all those
letters stand for and while I'm relatively handy and (I'd like to think)
intelligent, I don't have much (OK, any) experience with HVAC. What the
heck does "EAC" mean, anyway? (I'm sure that I'll smack my forehead
when someone tells me, but it's not coming to me right now.)

If you've read this so far, I greatly appreciate any insight Wow, I
apologize for how long this has become... only explanation I can offer
is when I start to get into a project, I really get into it until I
understand exactly what I have to do.

nate

EAC == Electronic Air Cleaner

Paul F.

On Jan 2, 5:27*pm, Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. *Currently the humidifier is enabled
whenever the fan is running. *I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. *Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. *This allows the humidifier to operate when there is no
heat call. *What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.

thanks,

Nate
--
replace "roosters" with "cox" to reply.http://members.cox.net/njnagel

You are still evaporating water without heat on, just less. Do you
have an accurate humidistat, analog need calibration every year. If
you condense anywhere you have to much humidity, April air sells a
system that tracks outside temp and automaticly keeps you set point,
which you set at just under condensation. How much water per day does
it use

On Jan 3, 7:29*am, Mikepier wrote:
On Jan 2, 8:21*pm, Mikepier wrote:

I have an Aprilaire hooked up to my furnace also, but it only comes on
when heat calls, not when the fan is running by itself. I just checked
the wiring on my furnace and the humidifier is hooked up to the W and
C terminals on the circuit board, so you can check if thats correct on
your furnace. You might have your humidifier wired up wrong and thats
why it comes on even if you only have the fan running.

My partucular model has no blower, it's mounted outside the return
plenum and it's only the 24VAC that opertes it.
I was not aware there are 120VAC models with blowers, so I have a
totally different animal than you.

That leaves me confused because previously you said the humidifier was
plugged into a 120V outlet on the furnace. The Aprilaire's I'm
familiar with that require 120V use powered fans and mount on the hot
side. The bypass models do not use 120V and mount on the return.

I have an Aprilaire powered unit that is connected the way you want.
When I installed it, I found 2 convenient 24V terminals that come on
when the gas burner is on. You should be able to do the same thing.

But, on another note, I'm wondering how energy efficient your whole
situation is. I would think constantly running the blower to even
out temp differences presents two problems:

1 - The blower constantly running uses a considerable amount of
electricity.

2 - Constantly moving room temp air through ducts has to result in
some additional heat loss, which I would think could be
considerable. For example, in my house the ducts run through the
basement, some up outside walls, where due to the ducts vs wall size,
mean those ducts have no insulation around them inside the walls,
etc. Also, most duct systems are far from perfect with some air
leakage, etc. The more air moved through there, the more loss.

I would suggest looking at:

balancing the system better by closing off some of the downstairs
registers, particularly those that are on a duct run that also serves
upstairs

consider getting booster fans, either the kind that sit at the
registers and come on automatically with the heat, or the kind that
you can insert into ducts and wire to the furnace blower or other AC

consider some small electric heaters upstairs to supplement the
existing heat

Paul Franklin wrote:
On Fri, 02 Jan 2009 23:21:44 -0500, Nate Nagel
wrote:

Nate Nagel wrote:
Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom
gets as
cold as 62 degrees when the downstairs, where the thermostat is
located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it
myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.

While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.
It's already got the humidistat control, the problem is that it gets
so dry indoors when it is cold out that it's calling for it to run
near continuously. This means that when the fan is running but the
furnace isn't firing, there's still water flowing through the
humidifier which is likely mostly going down the drain rather than
into the air. I'd rather fix it so that it only runs when the furnace
is actually firing so most of the water gets into the air and then it
shuts off when it goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate

Follow up: I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. So I
figured that it must be controlled by cutting power to the receptacle
that it's plugged into. Unplugged it, powered furnace back up, 120V at
receptacle. Waited for heating cycle to finish. 0V at receptacle
(which is mounted on the outside of the furnace) OK, so there's a relay
inside there that is cutting the 120V to the humidifier to shut it off.
Powered furnace back down again, opened up control box. I see that
there is a "HUM" terminal but nothing is connected to it. There is a
pair of black and white THHN entering the area the white is connected to
neutral and the black is connected to "EAC." Not sure what that stands
for - but I suspect that that is somehow controlling the humidifier
because it's obviously field wiring (looped 14AWG rather than a stranded
wire with a factory crimped end.) I can't see where it goes, but am I
on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? I'd check 'em myself but it's kinda hard to keep
my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. It's pretty hard to
pull the cover on the recep box too, once it's warm I really need to
relocate a lot of this stuff to make it more user friendly (one screw is
partially blocked by a drain line, etc.)

thanks

nate

More info...

I took the humidifier apart to check it out... has its own internal
24VAC transformer, but the blower motor is 120VAC. Also, after much web
searching, it appears that "EAC" is usually 120VAC and does in fact go
hot when the blower is active, "HUM" is usually 24V and goes hot only
when there is a heat call. I guess I still need to verify this with a
meter on my particular furnace because neither the board nor the wiring
diagram pasted on the inside cover explicitly states. Unfortunately
Ruud's web site seems to be completely down otherwise I'd just look for
install docs... (the "owner's manual" that the PO's left us is useless)
I assume that "common" is a common neutral for everything 120 or 24?

Am I mostly correct so far?

So... it would seem that the easiest way to make this work is to ditch
the wires coming from "EAC" and "COM" which presumably run straight to
the recep for the humidifier, wire that recep always hot, then run a
pair from "HUM" and "COM" to a 24VAC ice cube/PAM/whatever and intercept
one of the legs from the humidistat? Actually I wouldn't even
theoretically have to rewire the recep if I'm understanding this
correctly, but I like to keep things clean and easily understandable so
nobody looks at my work and goes "what the hell was he thinking?" Also
that would make it neater if I were to have to replace the humidistat
down the road because if I understand it correctly the newer electronic
ones need a constant 24V (which I assume I could pick off of the xformer
built into the humidifier) and like to be powered up all the time not
just when the air handler is running.

Is there some handy online magic decoder ring for all the terminal
designations for HVAC stuff, e.g. furnace control board, thermostat, and
humidistat? I've DL'd all the manuals I can for equip. that I have but
it seems that there is a basic assumption that one knows what all those
letters stand for and while I'm relatively handy and (I'd like to think)
intelligent, I don't have much (OK, any) experience with HVAC. What the
heck does "EAC" mean, anyway? (I'm sure that I'll smack my forehead
when someone tells me, but it's not coming to me right now.)

If you've read this so far, I greatly appreciate any insight Wow, I
apologize for how long this has become... only explanation I can offer
is when I start to get into a project, I really get into it until I
understand exactly what I have to do.

nate

EAC == Electronic Air Cleaner

Paul F.

D'oh! that makes sense. My "HUM" terminal must be 24V that would
explain everything. I do have an air cleaner, but it was installed with
the A/C and is not connected to the furnace control as it has its own
control (differential pressure switch turns it on)

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

wrote:
On Jan 3, 7:29 am, Mikepier wrote:
On Jan 2, 8:21 pm, Mikepier wrote:

I have an Aprilaire hooked up to my furnace also, but it only comes on
when heat calls, not when the fan is running by itself. I just checked
the wiring on my furnace and the humidifier is hooked up to the W and
C terminals on the circuit board, so you can check if thats correct on
your furnace. You might have your humidifier wired up wrong and thats
why it comes on even if you only have the fan running.
My partucular model has no blower, it's mounted outside the return
plenum and it's only the 24VAC that opertes it.
I was not aware there are 120VAC models with blowers, so I have a
totally different animal than you.

That leaves me confused because previously you said the humidifier was
plugged into a 120V outlet on the furnace. The Aprilaire's I'm
familiar with that require 120V use powered fans and mount on the hot
side. The bypass models do not use 120V and mount on the return.

I have an Aprilaire powered unit that is connected the way you want.
When I installed it, I found 2 convenient 24V terminals that come on
when the gas burner is on. You should be able to do the same thing.

Right, I was just kind of hoping that someone could point me in the
right direction before I had to draft a helper to turn on/off the
thermostat while I probe around in there.


But, on another note, I'm wondering how energy efficient your whole
situation is. I would think constantly running the blower to even
out temp differences presents two problems:

1 - The blower constantly running uses a considerable amount of
electricity.

2 - Constantly moving room temp air through ducts has to result in
some additional heat loss, which I would think could be
considerable. For example, in my house the ducts run through the
basement, some up outside walls, where due to the ducts vs wall size,
mean those ducts have no insulation around them inside the walls,
etc. Also, most duct systems are far from perfect with some air
leakage, etc. The more air moved through there, the more loss.


Meh, not so much. I am only aware of one "hot" duct that runs up an
outside wall. Most of the ductwork runs right up the center of the
house. I agree, loss of any kind is bad, but I don't think there is a
whole lot.

I would suggest looking at:

balancing the system better by closing off some of the downstairs
registers, particularly those that are on a duct run that also serves
upstairs

I have done this, although some of the dampers do not close all the way.
I'm trying to get the design department to agree on a style/finish and
replace all of the registers/return grilles throughout the house.


consider getting booster fans, either the kind that sit at the
registers and come on automatically with the heat, or the kind that
you can insert into ducts and wire to the furnace blower or other AC

consider some small electric heaters upstairs to supplement the
existing heat

Not sure how this would help...? problem seems to be that the masonry
walls of the 1st floor simply lose heat at a much slower rate than the
wood framed walls upstairs. I ASSume that the eventual solution is to
insulate the upstairs walls, but until I can afford to do that I'm just
trying to keep it comfortable inside... Only really need to do this
when it drops below about 25 degrees outside which is not that often.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

That leaves me confused because previously you said the humidifier was
plugged into a 120V outlet on the furnace. * The Aprilaire's I'm
familiar with that require 120V use powered fans and mount on the hot
side. * *The bypass models do not use 120V and mount on the return.

In my first post( 4th one down) I never metioned 120V on my unit. Are
you referring to the OP?

Nate Nagel wrote:

... the problem is that it gets so dry indoors when it is cold out
that it's calling for it to run near continuously.

Airseal the house.

Nick

On Jan 3, 10:20*am, Nate Nagel wrote:
wrote:
On Jan 3, 7:29 am, Mikepier wrote:
On Jan 2, 8:21 pm, Mikepier wrote:

I have an Aprilaire hooked up to my furnace also, but it only comes on
when heat calls, not when the fan is running by itself. I just checked
the wiring on my furnace and the humidifier is hooked up to the W and
C terminals on the circuit board, so you can check if thats correct on
your furnace. You might have your humidifier wired up wrong and thats
why it comes on even if you only have the fan running.
My partucular model has no blower, it's mounted outside the return
plenum and it's only the 24VAC that opertes it.
I was not aware there are 120VAC models with blowers, so I have a
totally different animal than you.

That leaves me confused because previously you said the humidifier was
plugged into a 120V outlet on the furnace. * The Aprilaire's I'm
familiar with that require 120V use powered fans and mount on the hot
side. * *The bypass models do not use 120V and mount on the return.

I have an Aprilaire powered unit that is connected the way you want.
When I installed it, I found 2 convenient 24V terminals that come on
when the gas burner is on. * You should be able to do the same thing.

Right, I was just kind of hoping that someone could point me in the
right direction before I had to draft a helper to turn on/off the
thermostat while I probe around in there.







But, on another note, I'm wondering how energy efficient your whole
situation is. * I would think constantly running the blower to even
out temp differences presents two problems:

1 - The blower constantly running uses a considerable amount of
electricity.

2 - Constantly moving room temp air through ducts has to result in
some additional heat loss, which I would think could be
considerable. * For example, in my house the ducts run through the
basement, some up outside walls, where due to the ducts vs wall size,
mean those ducts have no insulation around them inside the walls,
etc. * Also, most duct systems are far from perfect with some air
leakage, etc. * The more air moved through there, the more loss.

Meh, not so much. *I am only aware of one "hot" duct that runs up an
outside wall. *Most of the ductwork runs right up the center of the
house. *I agree, loss of any kind is bad, but I don't think there is a
whole lot.

I would suggest looking at:

balancing the system better by closing off some of the downstairs
registers, particularly those that are on a duct run that also serves
upstairs

I have done this, although some of the dampers do not close all the way.
* I'm trying to get the design department to agree on a style/finish and
replace all of the registers/return grilles throughout the house.



consider getting booster fans, either the kind that sit at the
registers and come on automatically with the heat, or the kind that
you can insert into ducts and wire to the furnace blower or other AC

consider some small electric heaters upstairs to supplement the
existing heat

Not sure how this would help...?

The aux blowers help by moving MORE hot air upstairs when the furnace
does run. An additonal small electric heater in an upstairs bedroom
could use less electric than running that big blower all night

Also, along the line of what Nick said, if the humidifier is
constantly running, it suggests moisture is somehow escaping at a high
rate. That could be due to a lack of vapor barrier or air leaks.
With it constantly running and very cold, I'd be concerned about where
that water is going and condensing.




*problem seems to be that the masonry
walls of the 1st floor simply lose heat at a much slower rate than the
wood framed walls upstairs. *I ASSume that the eventual solution is to
insulate the upstairs walls, but until I can afford to do that I'm just
trying to keep it comfortable inside... *Only really need to do this
when it drops below about 25 degrees outside which is not that often.

nate

--
replace "roosters" with "cox" to reply.http://members.cox.net/njnagel- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

On Jan 3, 10:35*am, Mikepier wrote:
That leaves me confused because previously you said the humidifier was
plugged into a 120V outlet on the furnace. * The Aprilaire's I'm
familiar with that require 120V use powered fans and mount on the hot
side. * *The bypass models do not use 120V and mount on the return.

In my first post( 4th one down) I never metioned 120V on my unit. *Are
you referring to the OP?

Yes, sorry got the posts mixed up.

Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets so
dry indoors when it is cold out that it's calling for it to run near
continuously. This means that when the fan is running but the furnace
isn't firing, there's still water flowing through the humidifier which
is likely mostly going down the drain rather than into the air. I'd
rather fix it so that it only runs when the furnace is actually firing
so most of the water gets into the air and then it shuts off when it
goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate


Well, after all that I got lucky. Drafted the girl to work the
thermostat while I probed the connectors on the control board (oh, that
sounds so dirty) here my furnace has a 120VAC "HUM" terminal so I moved
one wire about an inch and now it works correctly. Didn't have to buy a
relay or anything.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing? I
bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.

thanks,

Nate
Hi,
Your humidistat will llow it to run only when humidity is needed as is.
No need to change anything.

Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom gets as
cold as 62 degrees when the downstairs, where the thermostat is located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets so
dry indoors when it is cold out that it's calling for it to run near
continuously. This means that when the fan is running but the furnace
isn't firing, there's still water flowing through the humidifier which
is likely mostly going down the drain rather than into the air. I'd
rather fix it so that it only runs when the furnace is actually firing
so most of the water gets into the air and then it shuts off when it
goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate

Hmmm,
When it is real cold outside you need less R.H. inside.

Nate Nagel wrote:
Nate Nagel wrote:
Pete C. wrote:
Nate Nagel wrote:
Hi all,

I have an old Aprilaire powered humidifier connected to my furnace,
which is an old Ruud 90+ gas unit. Currently the humidifier is enabled
whenever the fan is running. I assume that there is a terminal on the
board that goes hot when the fan runs, intended for this connection.
Here's the issue - it's cold enough here and the insulation in my house
is uneven enough, that currently I have the fan manually turned on low
speed all the time to provide circulation. Otherwise my bedroom
gets as
cold as 62 degrees when the downstairs, where the thermostat is
located,
is 67 degrees. This allows the humidifier to operate when there is no
heat call. What would be the best approach to change things around so
that the humidifier operates only when the furnace is actually firing?
I bet I could come up with something that works by looking at it
myself,
but I figured I'd throw this out there in case there were any "gotchas"
that I might overlook.


While you could simply reconnect it so that the burner firing enables
it, I'd suggest connecting it to a humidistat, so that when the fan is
running *and* the humidity is low it will run, and of course not run
when the humidity is high.

It's already got the humidistat control, the problem is that it gets
so dry indoors when it is cold out that it's calling for it to run
near continuously. This means that when the fan is running but the
furnace isn't firing, there's still water flowing through the
humidifier which is likely mostly going down the drain rather than
into the air. I'd rather fix it so that it only runs when the furnace
is actually firing so most of the water gets into the air and then it
shuts off when it goes back to the low speed circulation fan.

I suppose I could also move the humidifier feed over to the hot water
line, but I don't know if that would still work well when the furnace
isn't firing.

Nate


Follow up: I started looking at what I have closely, and the only
"control" wiring from the humidifier is to the humidistat itself. So I
figured that it must be controlled by cutting power to the receptacle
that it's plugged into. Unplugged it, powered furnace back up, 120V at
receptacle. Waited for heating cycle to finish. 0V at receptacle
(which is mounted on the outside of the furnace) OK, so there's a relay
inside there that is cutting the 120V to the humidifier to shut it off.
Powered furnace back down again, opened up control box. I see that
there is a "HUM" terminal but nothing is connected to it. There is a
pair of black and white THHN entering the area the white is connected to
neutral and the black is connected to "EAC." Not sure what that stands
for - but I suspect that that is somehow controlling the humidifier
because it's obviously field wiring (looped 14AWG rather than a stranded
wire with a factory crimped end.) I can't see where it goes, but am I
on the right track?

Main questions:

- What does "EAC" mean on a furnace control board?
- What are the typical voltages on the "HUM" and "EAC" terminals?
120VAC? 24VAC? 24VDC? I'd check 'em myself but it's kinda hard to keep
my thumb on the pin switch, hold a multimeter, *AND* operate the
thermostat upstairs I guess I'm wondering if that's just taking
120VAC direct to the recep or if there's a relay hidden somewhere in
there that I need to dig deeper to find and verify. It's pretty hard to
pull the cover on the recep box too, once it's warm I really need to
relocate a lot of this stuff to make it more user friendly (one screw is
partially blocked by a drain line, etc.)

thanks

nate

Hi,
EAC - Electronic air cleaner
HUM - Humidoifier