Question about Heating & Cooling

1 Answer

Lennox 80uhg3-75a-3 igniter sometimes doesn't light , left LED slow flash, right LED solid.

Furnace comes on and blows but no heat. Doesn't ignite. Crawled into the attic... checked the two sensors by the burner.... good continuity through the swithc. Furnace is ounted on it's side so left LED = bottom LED on the control board (slow blink) and the right LED is the top LED (always on). After checking the control board fuse (OK) and looking for burn marks ... put everything back together and it workd for a day and then quit again. Suggestions?

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 15,557 Answers

The ignitor can crack and cause this, also check and clean the flame sensor.

Posted on Nov 25, 2013

6 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Therinnaiguy
  • 1420 Answers

SOURCE: Goodman GMS90904CXA Wont ignite, light blinks 3 times

Ok, you either have a inducer fan issue or a pressure switch issue or a plugged vent pipe. The inducer turns on to establish a draft for the exhaust. If it is not working you will get this error code. If the pressure switch does not sense pressure caused by the inducer, it will give this code. If either the intake pipe or exhaust pipe is blocked (even y just a little) it will give you the same error code. If the condensate hose or receptical is plugged, again it will give you this error code. Good Luck!

Posted on Oct 21, 2008

  • 6 Answers

SOURCE: Goodman GMP075-3 ignition problem

bad board,i have had several board failures on goodman

Posted on Dec 31, 2008

  • 11 Answers

SOURCE: Ruud furnace Model URKA A030jK08 Code opt 589

sounds like the circuit running to your condenser powers your furnace. when u disconnect power to the furnace it will reset and run the blower on startup. check the tube connecting the vacuum switch to the induced draft motor. maybe a leak. good luck

Posted on Nov 24, 2009

Therinnaiguy
  • 1420 Answers

SOURCE: lennox diplomat furnace will not always ignite.

Maybe, look for bad wiring connections and retighten the ground wires from circuit board to cabinet. Take a can of air and clean the burner tubes being careful not to blow on the igniter. Are ther any error codes blinking when it does not light? Read on for some more tips.

On a call for heat, the 24 volt thermostat sends a signal to the control module. The control module will indicate a call for heat with a light on the control either blinking or remain solid depending upon model. The inducer (exhaust) blower will purge all gasses from the furnace and pressurize a pressure switch. Once the pressure switch tells the module to continue, the electronic ignition will energize and send 120 volts to the igniter. The igniter will glow and you will be able to see it if viewed thru the small inspection port. Once the igniter gets hot enough, it sends a signal to the module opening up the gas valve (24 volts). Either a pilot will come on or the burner tube will ignite then spread the flame to all burners. Lastly a safety sensor will be looking for a certain temperature within a few seconds and the furnace will continue to operate and the room air blower will turn on in a minute or two.

What could go wrong? The unit will not run if there is no signal from the thermostat (bad thermostat or broken wire), the control module does not sense a signal from the thermostat (bad control), the inducer does not energize (bad motor), the pressure switch does not close (blocked vent piping, bad switch, plugged condensate hose), the igniter does not energize (bad control, bad igniter), the gas valve does not open or there is no gas (bad gas valve, broken wire, no gas), the pilot does not light (dirty pilot), the burner does not light (bad burner, plugged orifice, not enough combustion air), the flame does not spread to each burner (bad flame spreader, dirty flame spreader, more bad burners), the flame safety sensor does not detect flame (dirty or bad flame spreader, bad flame sensor, broken wire, bad control), or the room air blower does not energize (bad fan motor, bad control).

Posted on Dec 29, 2009

  • 288 Answers

SOURCE: Goodman furnace burner ignites then shuts off in about 10 seconds

if you have replaced the flame sensor and it will not stay lit, the draft safety switch may be opening. It works on positive and negative pressure created by the inducer fan motor.You may have a restriction in your heat exchanger or if is a high efficiency furnace, it may not have the drain tube installed properly with a trap. The trap works just like the trap under your sink and if water isnt in the trap, the pressures can be effected enough to open the draft switch(some call it an air pressure switch)

Posted on Jan 07, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Error code= two red flashes, lockout/ no flame


Trane XV80 hard lockout, 2 flashes, Can't be reset - DoItYourself ...

www.doityourself.com > ... > Gas and Oil Home Heating Furnaces
Jan 10, 2013 - The only way I can get diagnostic Red LED light to reset is to switch ... a2 flash with absolutely no operation from the furnace does seem to ..... inducer gets a demand you should get a pressure switch error code 3. ... the flame sensor wire and giving the furnace a heating demand after resetting power twice. Luxaire Furnace Blowing Cold - 8 Red LED Flashes
Mar 1, 2010
Winchester furnace diagnostics
Feb 14, 2010
American Standard Freedom 80 - Cold Air - Getting Error Code 9 ...
Nov 20, 2009
York ignition lockout due to retries
Dec 29, 2008
More results from www.doityourself.com

7 Tips and Tricks to repair your Furnace DIY - YouTube

? 13:25
https://www.youtube.com/watch?v=rAtcvPqUsBA
Dec 18, 2012 - Uploaded by JRESHOW .
cause this fault. 2 RED FLASHES: This indicates that thenormally open pressure ... The furnace will lock out for one hour and then restart. 7 RED FLASHES: This fault code indicates that the flame could not be established. This no-light ... problem. Bothheating and cooling operations will be affected. Check

Jan 23, 2016 | Heating & Cooling

2 Answers

Furnace computer won't let furnace light


What is the model number? I have an SLP98 (installed on 11/29/2011).... and if I take the cover off the front of the furnace the panel that has the fancy "Lennox" badge on it) you will see two clear round windows about the size of a half dollar (one high on the furnace box and one lower on the blower box.) If you look downward into the window on the blower box you can see a red LED display that will sometimes flash error codes like E228 (one character at a time). If your model has something like this, let me know. I've done some DIY fixes recently out of necessity....and their easy.....and several technicians confessed they didn't know much, if anything, about the newer high effieciency Lennox gas furnaces.

Mar 01, 2013 | Lennox Heating & Cooling

1 Answer

York Diamond 90 furnace blows cold air


There maybe a few issues. They have multiple safeties on furnaces. With this in mind this process to find the problem would take a Technician to check these safeties. It could be a flame sensor or thermocoupler each senses a flame or heat to keep the gas going. Also the damper for the flue must open for the gas to stay on. There may be more safeties on this and each safety sends a 24 volt current back to control module in order for the gas valve to stay open. If these aren't being met it will try around three times and go into a lock out mode which will keep gas shut off entirely.

Feb 21, 2012 | Heating & Cooling

1 Answer

Lennox gas furnace G21Q4/5-100-1 sometimes won't kick on


Hi check out the flame senser is clean also jump ou tthe pressure switch see if it lights when you do this , igntion modul is just a box with some push on wires just get the right one the info is all on the module

Feb 16, 2010 | Heating & Cooling

2 Answers

Lennox Fan will not come on when set to ''auto'' position.


Expensive is relative, service calls are never free. But if you have an idea what the problem is, you are armed against an unethical service company. Now to what you describe, could be a couple things, first let me explain the difference in fan speeds. Furnaces that both heat and cool have multi-speed blower motors. High speed is for cooling and lower speeds are for heating. The fan switch at the T-Stat turns on the high speed fan relay. The lower speed fan is turned on by either a temperature activated switch (silver box mounted on front on furnace above burners) or a time delay relay which is solid state. That being said, your problem could be a defective fan switch or one of your blower motor windings has gone bad. Most motors have 3 or 4 speeds and a technician could just change speeds and all would be good. A fan/limit switch is not so expensive that you would replace the unit. Bottom line, unless your really handy, a heating company is in your future. Good luck and please rate my answer if it was helpful to you.  

Dec 31, 2009 | Superior Lennox Blower Thermal Sensor -...

2 Answers

Lennox furnace 17 yeanrs old. flame comes on and the shuts down sometimes right away some times in a few minutes. We have the furnace go down to 58 at night. It takes all day to get back to 67.


Sounds like a dirty flame sensor.
Also 9 degrees is a large swing to recover. Most specialist will advise no more than a 5 degree set back, otherwise recovery time eliminates any savings you may achieve.

Dec 05, 2009 | Dayton (3E407) Heater

2 Answers

Lennox G40UH-60D-135-14 Furnace will not ignite


Do you have an inducer on the unit (no access to the lennox model number tonight)? That is a motor that comes on shortly before your unit fires that blows the combustion gases up through the flu. Does this motor come on at all if you have one? If it does and the furnace will not light, then there is a device on the unit called a pressure switch. This switch has two wires to it and a small tube that leaves it and goes to the inducer housing. Remove the tube from the inducer and blow into and draw in air lightly or until you hear clicking noises. Replace the hose and try again. Sometimes the pressure switch gets stuck but can also go bad. If everything is coming on all the way up to ignition but the unit won't come on, then it's probably one of the limit switches that need to be reset. These are little disks about the size of a penny and have two wires going to it. In the middle is a small button that can be pushed to reset it. Some units have 2 to 3 and others have more. You have to use a flash light and look all in the unit around the burners and around the flu pipe looking for the limits. Once you have found them all and tried to reset the unit, then try to start it up again. Hope this helps.

Apr 04, 2009 | Heating & Cooling

1 Answer

Furnace will not heat.


Most of the Lennox G-16s that I have repaired were having problems with the gray Penn-Johnson Piggyback igniton control module.
This is best repaired by replacing the spark module. Sometimes it may be neccesary to replace the gas valve also. Lennox updated to a ROBERTSHAW ignition system. Honeywell can also be used.
Also check that there is no water in the pressure switch or tube.
Hope this helps.
Matt
machtcl1@verizon.net

Jan 13, 2009 | Honeywell Electronic Programmable...

1 Answer

Carrier furnace blows heat constantly!


recheck your wiring iunside of the furnance around where yuou were working, you may have wired it wrong.

Dec 15, 2008 | Heating & Cooling

1 Answer

Carrier Weathermaker 8000 - furnace does not ignite


having a problem with a weather maker 8000. It will not come on at all unless I shut down the switch on the side of the furnace. filters is clean. it will start to light then stop

Dec 10, 2008 | Heating & Cooling

Not finding what you are looking for?
Heating & Cooling Logo

Related Topics:

122 people viewed this question

Ask a Question

Usually answered in minutes!

Top Heating & Cooling Experts

paulcarew

Level 3 Expert

2461 Answers

Dan Webster
Dan Webster

Level 3 Expert

8220 Answers

Donni Steen

Level 3 Expert

659 Answers

Are you a Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...