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Smart Valve- Armstrong furnace Dead

were Armstrong dealers, which is how I learned about the 80% bulletin, plus a little first hand knowledge too.

Now I will have to go dig in my Armstrong file for bulletins and see if I can find the bulletin on the 80% units and see if the horizontal 90% units are mentioned and I missed it or if it is a sepparate bulletin I never received. Either way I will remember what you said.


  • SaggsSaggs Posts: 174Member

    I have an Armstrong 91% LP furnace I installed 3yrs ago that is now unresponsive on a call for heat. No blower, no inducer, no fan, no nothing.. The green LED light is on steady on the Smart valve but nothing else. No flashing, no diagnostic code or anything. I tried jumping W and R, nothing. Jumped G and R and the ID blower comes on. I have continuity thru all the safeties and 24v at each safety. The inducer wont come on or the glow bar etc.. Not sure if it's the valve or the Armstrong Blower board. Any thoughts? Thx
  • Don_197Don_197 Posts: 184Member
    Wiggle The Molex Connector

    Wiggle the Molex Connector going into the Smart Valve......if it magically fires back'll have to replace the valve. Don't be fooled into thinking you fixed it.....IT WILL HAPPEN AGAIN SOON!!! I have been lulled into thinking this before.....and never even once got away with it. Always had to go back and change out the valve.

    Don Smet
  • DerheatmeisterDerheatmeister Posts: 959Member

    I Had that Molex Thing too.. that was a couple years ago !

    Just as a temporary solution at 23:00 ,i put a small wedge in it ,and change the valve a couple days later..
  • Home Depot EmployeeHome Depot Employee Posts: 329Member

    That was a common problem in the mid-90's is it back or just an old furnace?
  • Tombig_2Tombig_2 Posts: 231Member

    Do you have 120V to the inducer fan? The ignitor is controlled by the smart valve, forever renamed as the dumb valve for reasons previously stated, but the inducer fan is controlled by the board. It's either the board or the inducer.
  • SaggsSaggs Posts: 174Member

    I have no power to the inducer and I did try wiggling all the connectors, to no avail. The unit is 3 yrs old if that matters?
  • SaggsSaggs Posts: 174Member

    Anyone have any other thoughts on this as to wheter it's a defective valve or a bad board? Thx
  • tim smithtim smith Posts: 2,275Member
    Open limit???

    Main limit switch inside compartment probably right above gas valve at inside wall of furnace. 2 wires to it. May have to try jumping out only for test to see if it is bad. Or bad main board. Tim
  • SaggsSaggs Posts: 174Member

    Yah, I checked the main limt, that's what I thought at first because the filter was filthy but checked out ok. I'm getting a steady green LED on the valve, no diagnostic code. If you had to pick one of the two, would you go with the board?
  • Jim BennettJim Bennett Posts: 607Member
    I'd try....

    posing this question to Timmie at the bottom of the page. He's the gas appliance man.
    Jim Bennett
  • don_185don_185 Posts: 312Member
    need to know

    Need to know which smart valve you have and which board you
    have with model numbers.

    You most likely have the later version of the smart valve which would be the one with 3 connector.

    The only problem I have encounter with these new generation smartvalve from not working was, water from the inducer motor dripping down on top of them.

    Armstrong had two recalls on this furnace.
    1-Was the condensation dripping down on the valve.This is most likely your problem.When you get the new valve you will get a piece of metal to install that will divert the condensation away from the smart valve.

    2-The second recall on this furnace was the heatexchanger was being pulled away durring shipping or installation causing the pressure switch not to closed.
    Yes they had a fix for that as well however, its not a easy one.
  • Empire_2Empire_2 Posts: 2,343Member

    Replace the valve...They are still having problems with the 2nd gen. if smart valves. I had the same problen 2 months ago., Hi Don where have Ya been? All is well I hope.

    Mike T.
  • don_185don_185 Posts: 312Member
    Hi Mike

    Yes all is well and thanks for asking.I hope eveything has been great for you as well.

    Nothing but pm as of late and, praying to the gods that summer will come soon.

    Take care!

  • Glenn Harrison_2Glenn Harrison_2 Posts: 845Member
    Just so everyone knows.

    The smart valve he is talking about is the kind that controls everything except the blower, not the kind that just controls the burner.

    The green light being on steady is known as the "lights on but nobody is home" syndrome, a.k.a. the microprocessor has failed on the board in the "Smart Valve". So replace the Smart Valve if you haven't already.
  • Ray_14Ray_14 Posts: 17Member

    Also have a ignitor/sensor assembly with you. Armstrongs were built 10 minutes from me in OH so we have LOTS of them around. It always seems the assembly also goes bad when the valve does. Also, keep the info that comes with the new valve. It has a good chart for diagnosing Smart Valve problems.
  • SaggsSaggs Posts: 174Member

    Guys, really appreciate all the input to my problem. The Smart valve is a # SV9520H-8034, Armstrong furnace is a model # G1D91AU050D12B-2-A. I will get a new valve and ignitor assy and then replace the board if needed. Thanks again!!
  • Ray_14Ray_14 Posts: 17Member

    I think it is the gas valve. I just looked at the service manual, but there is no mention of the light staying on continuously. That valve does control the inducer. The G91BU series has the inducer running from the circuit board. The 'AU' series is ran from the valve. Let me know and I can fax you the info on that unit.

  • John Starcher_4John Starcher_4 Posts: 794Member

    ....has put together a manual on everything "smart" valve.

    You should contact him and order it. It has saved my butt more than once.
  • Tombig_2Tombig_2 Posts: 231Member

    Thanks for the heads up. I didn't know some models control the inducer as well.

    Tom G.
  • SaggsSaggs Posts: 174Member

    How do I get ahold of Timmie? I will order a new valve from Michel's if they don''t stock one. Thx again.
  • Glenn Harrison_2Glenn Harrison_2 Posts: 845Member
    No problem Tom

    I should add this model also uses a 120 volt ignitor and separate flame sensor, as apposed to the combo 24 volt ignitor sensor used with a pilot assembly.

    Here's a link to the manual for the Smart Valve refered to in the original post:
  • Glenn Harrison_2Glenn Harrison_2 Posts: 845Member
    You don't have to get an ignitor assembly

    if you don't want to. The ignitor is actually separate from the sensor on your particular unit. The smart valve you have is unique to Armstrong and Heil furnaces and is causing some slight confusion here between your smart valve and other smart valves out there. Your smart valve sends 120 volts to a separate ignitor that light the burners directly, as opposed to most smart valves that sends 24 volts to an ignitor/sensor that light a pilot assembly first, then the main burners. As I said before, if the light is on steady the microprocessor has failed on the board in the Smart Valve. The first generation of this particular smart valve did give Armstrong some problems, and was updated once if I remember correctly. Armstrong, as well as Heil/Tempstar has apparently lost their confidence in the Smart Valve as they have gotten away from it in the last couple of years.

    Here is a link to the manual for the Smart Valve in your furnace.

    Also, you can ohm out your ignitor to see if it's weak. A good Armstrong Ignitor (Norton number 601) should be between 50 and 300 ohms. If over 300, replace it.

    Last, all parts should be under warranty for 5 years on that Armstrong furnace, so make sure you take the old valve with you and return it for warranty.

    Good luck.
  • Glenn Harrison_2Glenn Harrison_2 Posts: 845Member
    You can contact Tim McElwain at

    gastc @ (remove the spaces on either side of the @ symbol). Tim has all sorts of excellent manuals on everyting related to burning gas and equipment.

    Also, if you didn't see it in my other post, here is a link to the manual for your particular smart valve:
  • Glenn Harrison_2Glenn Harrison_2 Posts: 845Member
    Just for the record Don

    the first bulletin you refered to for the shield only applies to the 80% efficiency Armstrong furnaces. saggs furnace is a 90% furnace.
  • don_185don_185 Posts: 312Member
    Thats odd

    Thats odd Glenn,why would it even be a issue on a 80% furnace?

    Just so you know.I can produce the bullentin if you need them.

    Not only is the shield recommended on all 90% horizontal furnace it was require on all the upflow and down flow models too, all the old models condensing furnaces.

    The new model this will no longer be a issue do to all the gas valve now set above the inducer motor.

    Also the 90% horizontal furnace is no longer made.

    Hope this helps clear up any confusion.

    I'm going to go on a hunch and say that your next question will be..don surely you have seen a 80% furnace with condensation issue? Was I right?

    Let me say yes, I have.And it was because the system was underfired or the airflow was not setup properly and....
    it was the wrong furnace for the application.
  • Glenn Harrison_2Glenn Harrison_2 Posts: 845Member
    O.K. Don you taught me something...

    as I never heard about using the shield on the horizontal 90% models. My appologies

    The bulletin I saw is to install the shield on the inducer motor above the smart valve to catch any condensate that might come down the flue and leak out where the flue joins the Inducer motor. Of course we all know there shoudn't be any condensate, but it has been known to happen.
  • don_185don_185 Posts: 312Member
    Hi Glenn

    No need for apology..we're here to help one another.

    I used to be a dealer for armstrong that the only reason I knew it to be fact.

  • Armstrong no longer

    using Smart Valve and the SV9520H diagnostics available on other Smart Valves.
This discussion has been closed.


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