Top 10 Goodman GMS90703BXA Heater Questions & Answers

I don't know where you are located, but there is a Goodman distributor in Sacramento, CA. Also in Ontario CA. They are a distributor so they may be able to help you or tell where to find someone who will help. Goodman is also known as GMC or Janitrol.

Most likely either a bad board or no gas to gas valve. Bleed out all air in the gas line. Check for 24 volts at both gas valve and circuit board terminals leading to gas valve. No voltage = bad board.

I Also have the same and other problems with my furnace model # GDS80703AXBB. First the LED kept blinking 4 times and I too jumped the primary limit, that didn't kelp. After several attemps I moved the wires going to the circut board and everything starting working again. After a week It stopped working again, so I pulled the plug out of the circut board checked all wires for for a bad connection plugged it back in. Now the LED blinks 6 times again I move the wires. Then the LED blinks 3 times. Then the transformer burns out. I have burned out 2 transformers and I have ordered a new circut board.

There is a small probe that is located inside the firebox and the flame from the burners will touch it. Typically it is located to either the far left or far right of the fire box if it is a vertical furnace. if the flame is not touching it or if it is taking the flame too long to travel across the burners (right to left or left to right) you will get this error code. Find the sensor and clean it with a small wire brush. Make sure what you think is the flame sensor is the flame sensor because the ignitor is very brittle and has two wires going to it. The flame sensor will have only one wire going to it. Also since you have the burner compartment open, inspect the flame spreader tray for blockage not allowing the flame to spread quickly. A can of air and the small wire brush will aide you in this cleaning.

Good luck to you!

Furnace attempted to start but failed after so manay tries. This may help you.

Sequence of operation, Gas Furnace.

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 ignitor. The ignitor will glow and you will be able to see it if viewed thru the small inspection port. Once the ignitor 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 ignitor does not energize (bad control, bad ignitor), the gas valve does not open or there is no gas (bad gas valve, broken wire, no gas), the pilot does not lite (dirty pilot), the burner does not lite (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).

Most newer furnaces will have a diagnostic center or control built into the control module. You may be able to view it as it is running thru a small viewing port. Some models will require the removal of an access panel prior to finding it. On the reverse of the access panel, there will be a diagnostic chart that will aide you in understanding any error code recorded (usually a blinking light).

This is why we technicians earn the big bucks!

Ohm out the safety switches also known as the high limits usually at least two on units they look like little buttons, with two wires going to each one. An open high limit will mean the circuit is not closed and allowing for the system to complete the circuitry to fire the heat, best way to diagnose is to jump out the suspected high limit s/w if the unit runs then you have your answer, but never, never leave the high limit switch jumped w/o the switch.

code 31 indicates pressure switch did not close or reopened during the heat cycle....1st thing to check is the inducer motor,,this is a small motor that turns a small blower wheel that draws the exhaust gases through the furnace and blows them into the vent pipe....1st locate the inducer assembly,,most easily identified by the small plastic fan blade that cools the inducer motor as it runs..1st turn off tstat and turn off furnace power switch..then turn on furnace switch,then set tstat to heat,set the temp above room temp by 5 degrees...remove the furnace front cover,locate the inducer motor,,if it isnt turning,but is warm or hot after a minute or so,likely the inducer motor is bad..if it isnt turning and isnt warm after 1 minute,then likely the main control board is bad,,not turning the inducer motor when it should,,,,,if the inducer motor is running,,then the pressure switch isnt closing,, could be a bad pressure switch but more likely there is a problem with the venting...some possible problems that would cause the pressure switch not to close in an 80% eff furnace [metal vent pipe] are: [1] a blockage in the vent pipe,base of chimney,dead bird at the furnace where vent connects to furnace or down inside the inducer assy,accessed by removing vent pipe from furnace....if all clear the chimney could be blocked up inside,,is the draft good when vent is removed from base of chimney?..if furnace is a 90%+ type [pvc plastic vent pipe],,then check the intake pipe at the furnace by removing it where it attaches to top of furnace..is the intake clogged with anything?..then check the intake and exhaust pipes outside for blockages,,including ice/frost/snow at the exhaust pipe outlet..

You have a limit switch located in the furnace (a little bigger than a dime and located near the center of the front panel, sometimes the switch is mounted to a small fiberglass board) . There will be two wires going to it. They sometimes trip so often that they fail to automatically reset(due to dirty filters or undersized ductwork). You can SHUT OFF POWER TO THE FURNACE, then remove the two screws holding the switch in the furnace, pull the switch out of the furnace and tap on it and wipe it off.
The switch may work a few more times but should be replaced with the same size and type. You will see some rating printed on the switch somewhere. Write down all the numbers and get a replacemet from a furnace/AC supply house. If you have a meter and know how to use it you could check the switch for continuity.

Sometimes just a tap on the switch will get it going. There will also be a couple of rollout switches that could be tripped. They have little buttons on them to reset them. If they trip it may have other issues to be solved.
Hope this helps!
Matt

Possible solution would be to push the reset button if you haven't already. I have had to do it twice on my dc90 in the last week.

If you look at the glass where you can see the combustion chamber, the glass is oval, follow the long axis of the oval toward the 'top' of the ignition chamber (my unit is laying down, with the blower on the west end and the combustion chamber on the east, as I am facing south). On top of the chamber are two protected spade clips. In between them is the reset. Make sure that the unit is off, press the button, and fire it back up.

One of the drain tubes (overflow) is plugged. Unhook each one and clear them of any debris.