Aprilaire / Furnace always on UPDATE

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Hello.. I have measured 55volts across W and C on the Furnace. Is this normal? I noticed that the problem goes away if i disconnect W. (The problem is that a correctly wired Aprilaire 500 with digital control is causing the furnace to run constantly).
Should W have voltage on it while the furnace isn't running?
W reads 55volts at the furnace but only 24volts at the humidifier end. Is this right?
FYI when i disconnected W, the humifier--with the Blower Activation Feature enabled--properly ran the furnace blower-only during the test cycle. With W connected, the humidifier properly tests and works but the furnace won't shut off.
Thank you, Dan
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Your installer is an idiot..... call somebody who knows WTF they are doing.
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Got it. Now... please explain why the voltage can be so high on W -- while running or not running! Thank you, Dan
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On 2/3/2011 3:20 PM, Martinic wrote:

I'd like a peek at the credentials of the meter operator.
No offense.
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Oh, i'd be the first to admit that i'm not 100% sure about operating mulitmeters; however, the other readings are fine (25v across R and C for example), so i'm pretty sure that i'm reading correctly.
What's funny is how W (touching W and C on furnace) reads 55volts wether or not the furnace is running! Why might that be? (This reading taken while humidistat is disconnected from W.)
Thank you, Dan
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wrote:

Oh, i'd be the first to admit that i'm not 100% sure about operating mulitmeters; however, the other readings are fine (25v across R and C for example), so i'm pretty sure that i'm reading correctly.
What's funny is how W (touching W and C on furnace) reads 55volts wether or not the furnace is running! Why might that be? (This reading taken while humidistat is disconnected from W.)
Thank you, Dan
Its already been explained, as well as how to fix it ....
As I have been saying.... Your installer is an idiot, call somebody that knows WTF they're doing *BEFORE* you do damage to the furnace, humidifier, and/or controls(if you haven't already).
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Martinic wrote:

I think you haven't got a clue what is going on. Let me ask one question, what exactly was in the humidifier box. Was there any 120V to 24V transformer? If you really read 55V it is way too high. Can you read and understand electrica/electronic diagrams? If not, don't mess around seek for expert's help and learn something before you cause expensive damage.
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Tony.. 10 years ago i installed the same units for 4 buddies and myself (the control is now digital). In the box came a very clear and simple wiring diagram and the transformer. I wired the 120v-24v transformer in an existing electrical box and fed the H terminal on the humidistat from there (independent of furnace obviously) as per diagram.
The wiring is bang on. I suspect there is something wrong with the furnace control or wiring, and it seems that Steve or someone has already explained it all, but i either i forget or can't seem to find that post?
:D
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diagram.

Then the transformer is to power the solenoid valve for water. My guess is the two wires going to W and G terminal is logic [and] gate in the control logic circuit. Having transformer I don't see why two wire goes to C and R terminals. My fax nu. is 403-257-5057, if you don't mind fax me the wiring diagram. Logic curcuits are sensitive to static charge and little electric mishaps it can go bad in a heart beat. Hope it is not cooked yet. Tony in Calgary, EE class of '60, VE6CGX. Retired from Honeywell.
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Tony.. i will try to fax the diagram to you tomorrow. Thank you! Dan
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Tony.. i have found it online.. can i email you the file (.pdf)?
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Nevermind--i got your email and just sent it! Thanks, Dan
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I got your email with pdf. I already replied. Good luck. If they show logic circuit of the humidistat I could tell you what exactly is going on. I hope you understand my reply. Tony
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Gentlemen... i have found the wiring diagram online.. follow this link, scroll down to "Current Residential Manuals", and click on "Model 500 series saftey and installation instructions":
http://www.aprilairepartners.com/products/category/humidifiers
What's interesting is that i found another Aprilaire diagram for the 500a showing something completely different--R and C go to the supplied transformer, and both Hs go straight to the solonoid:
http://www.filtersamerica.com/humidifier/whole-house-humidifier/aprilaire-humidifier/install_500A.pdf
My 500a came with the diagram from the link above.
Thank you, Dan
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(The first link showing R and C to furnace then H looping through supplied transformer)
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Got it. Now... please explain why the voltage can be so high on W -- while running or not running!
Thank you, Dan
That has already been explained.... you didn't pay attention.
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"Martinic" wrote in message
Hello.. I have measured 55volts across W and C on the Furnace. Is this normal? I noticed that the problem goes away if i disconnect W. (The problem is that a correctly wired Aprilaire 500 with digital control is causing the furnace to run constantly).
Should W have voltage on it while the furnace isn't running?
W reads 55volts at the furnace but only 24volts at the humidifier end. Is this right?
FYI when i disconnected W, the humifier--with the Blower Activation Feature enabled--properly ran the furnace blower-only during the test cycle. With W connected, the humidifier properly tests and works but the furnace won't shut off.
Thank you, Dan
You are welcome, idiot installer with a learning disability.
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On Feb 3, 9:18pm, "Stormin Mormon"

glegroups.com...
I like to think that some people enjoy helping others with their knowledge etc. I certainly do when it's something i actually know about--or even don't. Maybe we're just suckers. Ah, well. In any case, i think i "receive" help well? That is, you'll never hear me complain about it or in which way it's delivered :)
:Dan
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On Thu, 3 Feb 2011 19:28:58 -0800 (PST), Martinic

    Ohh,.... my .... god.......
    Stormy - SHUT THE FUCK UP !!!!!

message
    To the OP - 'Stormy Mormy' has been making an asshole out of himself here for many years. He knows slightly less than you about heating and cooling ( as hard as that may be to conceive ).
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
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On Feb 3, 9:19pm, "Stormin Mormon"

No, but it seems that i may have uncovered a problem with the furnace itself that has apparently been there for a long, long time. Perhaps my "f*cking around" may in fact save this home (not mine, btw)! Too funny!
:D
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