Heating, Air Conditioning, Fridge, HVAC/Nordyne g6ra
My problem is with a RA 80+ Upflow/Horizontal furnace (G6RA), installed about 14 years ago. It has worked great for 7 years, until yesterday. The burner will not ignite. The sequence that occurs is: 1) inducer comes on triggered by thermostat, and continues to run throughout the following sequence; 2) the board's red light comes on, no yellow light; 3) a small click noise happens; 4) the igniter glows hot for 30 seconds or so; 5) no gas emits; 6) as the igniter begins to fade, a clunk noise sounds from and is felt at the gas valve; 7) about 30 seconds later the red light flashes three times in a row, three consecutive times (pressure switch stuck closed); 8) the system goes quiet for a few seconds, with no inducer fan running, then the sequence restarts and repeats without end.
I have checked the pressure switch and the contacts inside move with slight vacuum. The rubber tube is good with no holes. I also jumped the orange wires leading to the pressure switch, after the inducer fan comes on. The furnace still will not fire.
Thank you for your help!
When the gas valve opens do you smell gas? " a clunk noise sounds from and is felt at the gas valve " If the gas valve actually opened you should smell gas. I looked at the pdf file on your unit, I would check the gas pressure at the gas valve first,if your unit is propane and elevation is 0-1999 ft and from 5000-5999 it's 10" from 2000-4999 it's 8.5" if you have natural gas and elevation is from 0-5000 ft it's 3.5". Your also suppose to have a minimum and maximum gas pressure in your line prior to reaching your furnace, the pdf file tells you these limits, so you would also need to check this also along with the gas pressure at the gas valve.
Your inducer/ventor/purge motor is suppose to stay running all the time that your calling for heat.You state it shuts down ( three flashes ) "the system goes quiet for a few seconds,with no inducer fan running" You would need to verify you are feeding 120 volt ac ( if this is a 120 volt furnace ) at point 1 and 4 at the control board. if the voltage drops out at anytime ,your inducer is OK and you may have a bad board,if your inducer drops out and you still have 120 volt, you have an issue with the inducer motor.
Me personally, if you check your gas pressure(s) and it's correct,and you loose 120 volt ac power feeding the inducer ( whenever your calling for heat ) and you feel all your limit controls work as they are suppose to ,and do not trip, I would be a parts changer , replace board, flame sensor and ignitor ( glow coil ) also the pressure switch. Buy via Internet.There are many HVAC Companies that sell parts. For what it cost you to call for service and they just replaced one repair item, you can replace several items at a reasonable cost and still be well under what a service call and just one item a Company would charge
From the PDF file
The flame sensor acts to prove that flame has
carried over from the igniter to the opposite end
burner. If no flame is sensed, the furnace will
shut down within 7 seconds of ignition.
Download your installation instruction and follow closely. Goggle Nordyne g6ra