I have a Rheem Classic Series Super quiet 80 gas. My burners will not light, the fan just blows but no heat. I followed the instructions on the extirior of the unit but still no flame. Any Ideas?

1) Copy following link to troubleshoot by type of gas control valve:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

2) Bad gas control valve, low gas pressure, dirty combustion parts, inadequate venting, clogged flame arrestor screen located under burner

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

`1) Copy following link to troubleshoot by type of gas control valve, blower motor links, pressure switch testing, and other professional resources:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
http://www.thetankatwaterheaterrescue.com/forums/forum3/

2) Power-vent blower motor can go bad.
Plug motor directly into outlet, or turn on-off switch on, and see if motor works.
Check outlet for correct polarity, and for at least 80% of rated voltage.
Check vacuum switch. Blower creates vacuum, and the vacuum switch detect vacuum, and signals gas control valve that burner sequence can continue.
Gas control valve can also go bad. Wiring etc can go bad.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Ignitor is probably too fare up. Adjust it lower !

Depending on the specific setup, there should be a reset in the gas line. Either a push OR pull button.

in front

Open a nearby window to let in plenty of air and see if problem continues.
Problem might be something simple like vent backflow blowing out pilot, or more complicated like bad gas control, or combination of problems listed below.
Suspects include:
Faulty gas control thermostat.
Air in gas line.
Low gas pressure.
Hot attic air.
Insufficient air, or dirty air intake.
Dirty combustion parts, and tubes.
Thermocouple not sitting in flame.
Thermocouple tightened too much. Finger tight + 1/4 turn. No joint compound or teflon tape.
Bad venting.
Backflow of air down vent pipe caused by tight house and/or other vent fans in house.

Open following link for resources, illustrations and reading:
http://waterheatertimer.org/How-to-install-gas-water-heater.html#clean
http://waterheatertimer.org/pdf/Bosch_Checking_the_draft.pdf
http://waterheatertimer.org/pdf/Pilot-light-will-not-stay-lit.pdf

When having a problem with pilot and burner, the place to start is troubleshoot section in your manual.
Whirlpool is probably made by Craftmaster which I believe is a Rheem company, and Rheem makes a number of different models.
Some models have specific manuals and others have generic manuals.
Open Rheem water heater page and click on water that matches your water heater. On page that opens, click on tab that says 'specs' and then download manual.
http://www.rheem.com/Products/tank_water_heaters/gas_water_heaters

If none of those water heaters look like yours, open following link to help identify company website and download manual. Craftmaster website does not have instruction manuals.
http://waterheatertimer.org/Water-heater-manufacturers.html

All gas water heaters require periodic maintenance.
Some require yearly maintenance.
The burner parts require cleaning.
http://waterheatertimer.org/images/Clean-burner-300.jpg
http://waterheatertimer.org/images/Clean-burner-250.jpg
http://waterheatertimer.org/How-to-install-gas-water-heater.html

1 clean flame sensor
2 clean burner YouTube video
3 clean heat exchanger
Start with 1,ect
Rheem website has instructions or call they will e-mail info.

Sounds like it could be a dirty or bad flame sensor.
When the burner lights ,there is a flame sensor in the flame and it is suppose to sense the flame and send a signal back to the control board which will keep the gas valve open, if it gets dirty or is bad it doesn't send the signal back to the board and the board will shut the gas valve off and after three tries it will lock out the furnace and you have to reset it to get it to work again.
The flame sensor looks like a wire and it's in the flame usually it will get gas deposits on it, then it won't work.
You can clean this sensor with an extra fine piece of steel wool, but before you attempt to do this DISCONNECT ALL POWER TO THE FURNACE.