Question about Air Conditioners

1 Answer

Heater lights for about 5 sec and then goes out

When you turn on the heat to my ruud package unit the ignitor lights the flame and then it goes out after about two tries the dianostics light binks once and the furnace shuts off please help

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 1,420 Answers
Re: heater lights for about 5 sec and then goes out

One flash on a Ruud furnace indicates failure to ignite. There is a viewing port on the furnace where you can watch the flame. If the ignitor is igniting the burner and then 2 or 3 seconds later, the flame goes out; you most likely have a flame sensor that is dirty or not working. Check to make sure you are getting gas. Check the connections of all wires to the control board. If the sensor is not part of the ignitor, see if you can get to it to clean it with a small wire brush. Make sure there is a good ground connection between the board and furnace frame. If the flame is not traveling all the way to the flame sensor, clean your burners. If the flame burns inside the burners, you may have weak gas pressure. Good Luck.

Posted on Oct 01, 2007

Add Your Answer

0 characters

Uploading: 0%


Complete. Click "Add" to insert your video. Add


3 Points

Related Questions:

1 Answer

My Ruud achhiever 90 starts to fire but as soon as the blower fires the burner goew out. I also noticed that the "igniter" on the end isnt firing. Could that cause the burner to not stay lit when the

There is an ignitor and a flame sensor. If the ignitor does not ignite the gas after a time, it goes out. If the flame sensor does not detect ignition the gas valve closes. When you start it you should see the ignitor come on like a light bulb and glow, then the gas valve opens and you get ignition. Then the flame detector turns on when the ignitor goes out. Flame detectors are like a chrome wire that has one connection to it and it sits part of the way in a burner. They get dirty and corroded. When that happens it shuts down. You can clean the flame detector with steel wool of scotch brite pads. Dont get too carried away doing that though.

Dec 25, 2012 | Air Conditioners

1 Answer

Lighting pilot on Ruud 80 plus furnace?

Hi, There is no pilot and the flame is lit by a hot surface ignitor... The hot surface ignitors go bad probably need to replace that...

Here is a tip that will help you try to figure out why your furnace is notworking.

BasicFurnace or Heating System Troubleshooting


May 14, 2011 | Ruud Air Conditioners

2 Answers

I have a Ruud Silhouette 2 gas furnace. The draft fan starts, ignitor then glows, main burners light and go out after a few seconds at the same time the ignitor goes off. I have replaced the flame sensor...

I had the same problum with my heater to no end. I thought it was the th-sat . still don't know if it was . one of the sencers I was feeling, and the disc snapped in and the heater ran but on heat. turn off power and unplug the power cord and removed the sencer and taped it until it pop back out and when it did I resemble back in place.repluged all back up. turn the heater back on and the flame stayed on . LET THEIR BE HEAT. I played with it for 4 hrs.I don't know if this was the problum .will have a teck look at it to be safe.

Dec 27, 2010 | Ruud UBHC Air Conditioner

1 Answer

I have a package unit rheem and the furnace want stay lit comes on for 3sec. and goes out i change out the flame sensor already and it still not want work.

You probably need to purchase and install a new ignitor. I would suggest that you inspect your ignitor closely for cracks. Make sure you do not touch the ignitor with your bare hands. If you do not visually see a crack, then you could have a furnace control board problem or a limit, or a rollout switch problem

Nov 30, 2010 | Ruud UAMB036 Air Conditioner

1 Answer

Have a ruud achiever 90 plus furnace. the flame goes out after the igniter quits. any ideas

Problem: Your furnace will not ignite the gas to produce heat for your home. When a furnace has a bad ignitor what I see most of the time is the following sequence of operation:

1. Thermostat calls for heat. 2. Draft inducer motor starts. 3. Pressure switch attached by a small plastic or rubber tube senses the negative pressure produced by the draft inducer and closes. 4. Draft inducer runs for 30 seconds to a minute before you hear a gas hissing sound. The ignitor did not glow, the flame sensor (a small metal probe about 1/8" in diameter, with a white porcelain base) does not sense the flame, so after 8 to 10 seconds the hissing sounds stops with no ignition of gas to heat your home. Your furnace shuts down and goes into a lock out condition until you turn your power switch back off and on again. Then the sequence starts all over again with no ignition of the gas. Solution: You probably need to purchase and install a new ignitor. I would suggest that you inspect your ignitor closely for cracks. Make sure you do not touch the ignitor with your bare hands. If you do not visually see a crack, then you could have a furnace control board problem or a limit, rollout switch problem. The furnace's control board might not be supplying the voltage to the ignitor. If your furnace lights and the gas stays on for 8 to 10 seconds, then shuts right back off, then you need to clean your flame sensor with light sand paper or steel wool. You might need a new flame sensor, but most of the time they can be cleaned an will work well after cleaning.

Nov 26, 2010 | Ruud UBHC Air Conditioner

2 Answers

I have the same Ruud Achiever unit & it's not working.

It sounds like it will need a hot surface igniter. This is the part that glows when furnace is turned on, and tells gas valve to release gas for it to ignite. At that point funace is lit, it heats up flame sensor witch inturn tells fan to start.

Sep 30, 2009 | Ruud UBHC Air Conditioner

3 Answers

Ruud heater will not light consistently

Your furnace is going into a lockout condition, cycling the power resets the circuit board and it starts over. I will need to know approximate age and model of your furnace, it sounds like you have need to clean the flame sensor rod. However i need to know what i am working with.

Dec 18, 2008 | Ruud UBHC Air Conditioner

Not finding what you are looking for?
Air Conditioners Logo

Related Topics:

1,619 people viewed this question

Ask a Question

Usually answered in minutes!

Top Air Conditioners Experts

Mike Butler
Mike Butler

Level 3 Expert

6674 Answers


Level 3 Expert

1033 Answers

Dan Webster
Dan Webster

Level 3 Expert

8147 Answers

Are you an Air Conditioner Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides