20 Most Recent Goodman GMS90703BXA Heater - Page 8 Questions & Answers

Hello, verify if the igniter is receiving a 120 volts from the control board after the pressure switch closes. Sometimes a faulty control board can cause this problem if the igniter and pressure switch are good.

if you are using a single stage with just a W connection not a W1 and W2 then it may be wired to the W1 connection on the furnace contro board. in that case it will only run in first stage. the easiest thing you can do is run a small piece of wire between W1 and W2 on the furnace control board. if you dont have a W1 and W2 connection on the board then its not 2stage, if you have an extra wire at the stat you can get a 2stage stat and wire W1 and W2 individually.

I see no problrm? what is wrong?

400-500

This fuse is used on the low voltage side of the furnace. All 24 volt controls operate thru it. You may have a short in your thermostst, thermostat wire or even a bad transformer. After replacing the fuse, inspect the wiring in the cabinet as well as the wire heading toward the thermostat for damage. If you find none, check the thermostat for loose wires or contacts. If all else fails, jump out R and W with a small jumper temporarly at the furnace and see if the unit runs. You will have to tape the door switch closed to run it with the panel off. Remember, this will keep the furnace running 100% of the time until you disconnect the jumpers. Not a solution, just a test! If it runs flawless, you have a bad thermostat or wire. Diagnosing a transformer is for a technician.

Based on your model number this furnace does not have a pilot light,instead it uses a hot surface igniter.typically it glows and when it gets hot enough the gas valve will open and the burners will light.When the igniter starts to go bad it will glow but not get hot enough to open the gas valve.If your furnace lights and the quickly goes out the flame sensor maybe dirty.

open the top of your unit so that you can see into the burner box
what your looking for should be an orange wire that leeads up to a metal rod
that metal rod should be in the way of the flame when unit is on
this is your flame ground,,, or more commonly known as the flame sensor,,, take this out and goive it a good brush with some steel wool
and reassemble,,
this should clear up you problem

3 blinks is the pressure switch not working i take it you have a reg on the line from the tank ?

Call back who ever fitted it , they is a years guarantee on it .

If pressure switch does not prove fan does not start on some models

it will be in the combustion chamber on the burner bar you will have to remove the burner to get to it .

Hello, you need to run 18 gauge thermostat wire from the Y and C terminals on the control board to each low voltage terminal on the outdoor contactor side terminals. Best way is th run it along the suction line and support it with wire ties. The high voltage wires will run from the disconnect box on the outside to the high voltage terminals on the contactor coil. The high voltage wires will be run in liquid tight conduit.

it's powerd by a relay and only comes on ondemand.

you must see the schematic diagram, and see what amp, and voltage is.If you have doub get customer support from Goodman.comGod bless you