dcsimg
Page 1 of 4 123 ... LastLast
Results 1 to 10 of 32

Thread: Armstrong furnace problems - won't stay lit

  1. #1

    Default Armstrong furnace problems - won't stay lit

    Hi everyone - My Armstrong furnace (Ultra V - Tech 80 model # G1N80AU075D16B-1A) doesn't seem to want to stay lit and provide the much needed warmth on this cold morning in Feb. The furance is about a year old - I installed it myself. It will light - run a few seconds and then go out. It will then try to restart several times but will eventually stop this cycle after x number of tries. With my very limited experience with furnaces (and none with new furnaces like this) it appears to be a problem with the sensor that confirms that the furnace did light and isn't just dumping gas into the heat exchanger.

    Any help would be sincerely appreciated.

    Scott

  2. #2

    Default

    There's a weird oxide that builds up on the flame sensor that causes intermittant flame sensing. You need to clean it off with steel wool or fine emory cloth. The flame sensor is a short, steel rod that goes through a ceramic insulator into the bottom (normally) of the combustion chamber. It has one quick connect wire on it, and it normally held in by 1 screw through a tab. Take the sensor out and scrub off all the nastiness and try her again. Should fix you up. If you can't find the flame sensor, follow the wire that is connected to the "sense" terminal of the ignition module and see where it goes. About a 5 minute job. Repost and let us know how you made out.

  3. #3

    Default

    Thanks for the quick reply - I did clean the flame sensor and sure enough, the furnace is running fine. I think its great you take the time to help others and sincerely appreciate your response. Hope I can return the favor some day (Hint: my expertise is in computers).

    Quote Originally Posted by mdshunk
    There's a weird oxide that builds up on the flame sensor that causes intermittant flame sensing. You need to clean it off with steel wool or fine emory cloth. The flame sensor is a short, steel rod that goes through a ceramic insulator into the bottom (normally) of the combustion chamber. It has one quick connect wire on it, and it normally held in by 1 screw through a tab. Take the sensor out and scrub off all the nastiness and try her again. Should fix you up. If you can't find the flame sensor, follow the wire that is connected to the "sense" terminal of the ignition module and see where it goes. About a 5 minute job. Repost and let us know how you made out.

  4. #4

    Default

    I'll let you in on a little industry secret. These flame sensors are becoming a real cash cow for HVAC service companies. The dispatcher almost knows what the problem is when the call is called in by the homeowner. The service tech may or may not elect to clean the sensor. Often, the homeowner is sold a new one off the truck. Other times, the service person will clean the sensor and report to the customer that the unit is "patched up" and will require a return visit (and another service charge) to install a new sensor. You would have paid at least 50 to 100 bucks for the guy to drive to your house and clean the sensor off. I'm not trying to say that the industry is filled with frauds... I'm just pointing out that this flame sensor should get your attention every couple of years. There's not much to do on a gas furnace except change filters often, drop of oil on circulator motors or blower motors if required, clean pilot burner on atmospheric furnaces, and for high efficiency furnaces... clean the flame sensor.

  5. #5
    Unregistered Guest

    Talking Thanks for the help!

    I ran into this same problem and cleaned the sensor and got the furnace going in under 10 minutes. Great and easy tip for someone who has never looked inside a furnace before.

  6. #6
    Unregistered Guest

    Question

    my furnace does the same thing used to be every couple of years now it's an anually(every season) recuring problem. Anyway to prevent the oxides from building in the first place?

  7. #7

    Default Ultra V tech

    I try to start the unit and it runs through all the cycles for ignition and the glow bar comes on and we get gas but no flame. I am having the same problem in another unit. This heater use natural gas for fuel. I tried to check if there was something blocking it in the exahust but nothing but day light. We also cleaned the flame sensor snd changed the gas valve but nothing seems to be working. Please help very cold.

  8. #8

    Default Ultra V tech

    I try to start the unit and it runs through all the cycles for ignition and the glow bar comes on and we get gas but no flame. I am having the same problem in another unit. This heater use natural gas for fuel. I tried to check if there was something blocking it in the exahust but nothing but day light. We also cleaned the flame sensor snd changed the gas valve but nothing seems to be working. Please help very cold.

  9. #9
    Join Date
    Jan 2006
    Location
    Western Wisconsin
    Posts
    320

    Default

    You know for a fact that the main burner of the gas valve is opening?...that you can smell gas?...to know you are getting gas? Or, have you gone out to look at the meter to see if the fast spin dial on the meter suddenly kicks in and then shuts down quickly?

    If it indeed is doing this, it sounds like you have a blockage at some hole where the gas comes out near the hot surface glow ignitor.

    If there was a low voltage safety circuit issue, or a weak glow, I don't think the furnace would be allowed to get this deep into the firing process before bailing out. Something is telling the control box that everything *is* kosher, to allow the gas valve to open. The fact it doesn't ignite seems like it would have to be an issue that the glow cannot reach the gas, quick enough. If this doesn't ignite quickly, the furnace will shut itself down.

  10. #10

    Default

    the best way to keep your furnace running without flame sensor problems is using ooo steel wool, emery cloth will create scratches in the sensor for more oxidization to occur.

    ps.. make sure its not ooo stainless steel wool.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Armstrong furnace issue. First 3 LED red lights now 4
    By kmsinar in forum Heating & Air Conditioning - Existing Home
    Replies: 1
    Last Post: April 9th, 2011, 09:46 PM
  2. Questions re: Armstrong Ultra V Tech 80 Furnace
    By jlschneck in forum Heating & Air Conditioning - Existing Home
    Replies: 0
    Last Post: November 30th, 2009, 06:02 PM
  3. Furnace will only stay lit with additional air input
    By snurb in forum Heating & Air Conditioning - Existing Home
    Replies: 0
    Last Post: December 24th, 2008, 01:08 AM
  4. Armstrong Ultra V Tech 80 furnace not working properly
    By lawheatley31 in forum Heating & Air Conditioning - Existing Home
    Replies: 0
    Last Post: December 6th, 2008, 05:05 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •