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Ruud furnace won't stay lit.

Our Ruud furnace has an electric ignition. When it get so hot the flames come on. But the flames only burn for about a minute then it cuts off. It is not reaching the temperature we have set on our thermostat. Do these kind of furnaces with this tye of starter have thermocouple. It reminds me of a furnace with a pilot lite. The fan goes ahead and blows for a while.

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  • kenneth889 Jan 29, 2009

    I have a Ruud Mod.#UGRA-07EMAES with same problem. Burners ignite for a few seconds and then go's out. The circuit board has a flashing yellow light. The troubleshooting chart on the furnace says to clean the flame sensor and if this does't work to replace the circuit board. Is there something else I should check before I buy and espensive board?

  • kburns1016 Apr 02, 2009

    I have a Rudd Model #UGRA-07EMAES 90 Plus Gas Furnace with a similar problem. Once it is turned on the inducer fan comes on, the igniter glows, the flame appears, the fire roars for a few seconds then the far left burner goes out causing the unit to shut down. We just purchased the house and prior to closing, all the utilites had been turned off for about a month. Prior to the utilites being turned off the furnace did work.

    We had the gas company come out and make sure we were getting the proper pressue into the house, and we cleaned the unit thoroughly.

  • Ken Bledsoe May 11, 2010

    When you say flame comes on for one minute is it that long or maybe just 20 to 30 seconds?

    Also is the air filter clean?

  • Howard Sexton Oct 06, 2012

    We have a new Ruud and it was doing the same thing. Found a spider nest in the fan vacuum line.



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Hi, welcome to Fixya. If you have spark ignition turn off the power and using sand cloth clean the rod(s) and hood of the spark ignition. If it is a Hot Surface Igniter (glow coil) look on the opposite end of the burners and you will see a rod protruding in to the flame. It's called a flame sensor. Clean it with the sanding cloth. If either of these works then you bought some time but should consider replacing the part fairly soon. Please report back to let us know your progress. Good luck.

Posted on Jan 25, 2009

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I had the displeasure of working on a Rudd GRA-70MAES spark ignition furnace and I never want to see one again! The circuit board would intermittently shut down the ignition after about four seconds and it takes six to seven seconds to open the gas valve (this problem has existed for years and no one has been able to fix it). I replaced the gas valve and the circuit board and things just got worse. I noticed the schematic diagram showed the "C or Common" terminal of the circuit board terminal strip as being grounded so I checked and there was no ground. The "C" terminal is also connected to a nine pin socket on the circuit board that has a nine pin plug with pin #9 of the plug connected to a ground wire. I removed the plug and pin #9 is grounded as it should be but there is no ground on pin #9 of the socket. The answer is there is a green (ground) wire connected to the nine pin plug but it is on pin #1 which connects to nothing on the circuit board socket. By the way, pin #9 is in the lower left hand corner of the plug and pin #1 is in the upper right hand corner. If you have a green wire in the upper right corner of the nine pin plug, you have one of Rudds mistakes. Rather than trying to get Rudd to admit to stupidity, try connecting a wire from the "C" terminal strip on the circuit board to a screw on the blower or any other ground and see if it does not cure your problem. Why this furnace ever worked in the first place is beyond me and why no one ever could fix it is obvious. Do yourself a favor and buy another brand furnace next time.

Posted on Feb 16, 2013

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I had the same problem with a new Ruud furnace. Found a spider nest in the fan vacuum line. Works great now.

Posted on Oct 06, 2012

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I have the same problem, but already replaced the fllame sensor with a brand new one. Still having the same problem. Any other ideas?

Posted on Mar 01, 2010

  • magnaduke Nov 06, 2010

    My unit had an error code for flame over switch open. Found it was my number 1 burner not shooting through the heat exchanger tube as the other 5. Orfice was fine. Talked to a local dealer and he said the echanger tube was split or messed up and I could just block off that burner and it would fine. Replaced orfice with plug and so far it is working.


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