I have a Rheem Criterion II gas furnace, that quit working. I checked it out, and found that the ignighter would come on, the gas would start, and then it would shut off. Figured it was the flame sensor. Before I could sand or replace it, it quit even doing that.

I didn't get voltage off the transformer, so I replaced that, and the flame sensor. Now, all I get is the right most green light on the controller board. The middle green light and the amber light don't light.

Does this mean a new controller board?

Check the thermostat wire connections at the furnace - perhaps one or more broke off while replacing the transformer. If not, try removing the thermostat & connecting the "R" & "W" wires together. If the unit starts/runs, the problem is the thermostat.

Tried connecting the "r" & "w" wires together, and still nothing. Next?

Check the thermostat wire connections at the furnace - perhaps one or more broke off while replacing the transformer.Did you check this too?

Yes. Wires good.

Look for a label, usually inside the blower area, with a list of codes & instructions. See if there are any useful hints or suggestions regarding the status light(s).

Nothing but a wiring diagram. Looked for the status light key first. :-)

If you can provide the complete model #, I may be able to come up with something.

RGDG10EBRJR, Thanks!

Peek here: Main Furnace Control Circuit Board Used in (Rheem, Ruud, Robertshaw): Best Buy Heating and Air Conditioning (http://bestbuyheatingandairconditioning.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=CIB69503&Category_Code=CB) Does this look like your circuit board? Do you have a voltmeter?

Looks kind of like it. I really didn't pay that much attention to the board, as I only had the cover off the case for a minute or so. Yes, I have a multi-meter.

Looks kind of like it. I didn't pay all that much attention to it, as I only had the case open for a minute or so.

I do have a multi-meter.

You were going to give me a few things to check? I could use the help, it is 0 degrees here...

Sorry man, I've been overwhelmed at work, long days...
The basic first step: Turn off power, then remove the "R" & "W" wires from the furnace & install a jumper from "R" to "W". Replace panels & restore power. Does the unit run? If so, the problem lies in the thermostat or wiring.

I figured you would be busy.

Try jumping r and w at control board in furnace as KC13 suggested. Let us know what happens. I really think both green lights should be on at all times when furnace is working correctly(wether there is a call for heat or not) If furnace is not working correctly, one of the green lights should be on steady and the other green lite should be blinking out a code. If one of the green lights just never comes on at all, I'm betting you are in need of a new control board. Don't worry about the orange light for now, as it is strictly a light to show condition of flame senser and will only glow when burners are lit.

Thanks guys. I appreciate your help...

Tried it, and the exhaust fan started for a second and that's it.

Ok, I replaced the board and it acts like a furnace again. However, only the two right burner tubes light up, the fire never makes it to the 2 left tubes. Since it never gets there, it doesn't heat up the flame sensor and it goes out.

What do I do next?

Clean the orifices and tubes carefully for the two burner tubes that do not light. DO NOT operate the system in this condition raw unburnt gas is possible being delivered into the combustion chamber and can go BOOM. Also clean the flame jumpers on all the burners.

It was the flame jumpers. I found a reference on another site, cleaned them all well, and it now works fine. Thanks!

Good deal good that you got it going.

Yah, since it got to -8 here last night, it was nice to wake up to a warm house!

Thanks again...

I can feel every ones pain when the gas bill arrives. With Natural gas being depressed price wise right now it will still be expensive and when the natural gas prices go up it will just be crazy.