1993 Comfortmaker RPG II Flame Sensor Not Working?

beenthere

Its just a piece of metal. If its dead, then the porcelain is cracked.

Northwoodslakes

OK folks, I removed and cleaned the Burner, and installed a new Flame Sensor. Furnace is still doing the exact same thing! Damn... (New Ignitor installed last Fall, and it was all running fine then.)

1.) With the Sensor wire attached it will burn for 1-2 seconds, then will go out every time. I then still get the same 6 red flashes every time, after the flame burns out, and then I flip the power switch and try again and again, etc.
2.) Now with the Sensor wire Unattached, the Burners do stay on much much longer, maybe 5-6 seconds, then go out. Why is this? And if I remember correctly, no flashing at all this time at the Control board after the flame goes out. Could my Control Board be the Culprit?
4.) Someone mentioned bad ground, and so I removed the Burner and sanded/wirebrushed the rusty film off the Burner face; and still no progress! I thought for sure this was going to do the job.
5.) I did replace the 24V transformer a few months back. I accidently shorted it out, screwing around and jumping some Control Board terminals, my stupidity. Could I have screwed something up then? I mean the AC works perfectly fine. The control board makes a short clicking sound and then the furnace ignitor starts to glows like always, then the Burners always do come on, but like I said ALWAYS go out quickly.
6.) My AC unit outside works perfectly fine. I've got my new digital Thermostat wired up; the 4 wires from the Therm. to the same matching terminals on the Control board in the Furnace. I've also have the 2 wires coming from the outside AC unit. 1 Black wire going to the "G" terminal on the Control board and the Blue wire to the "Y" terminal on the Control Board. Is this wiring proper for both the Heating and Cooling modes?

I tried to post some pics I took of my Furnace but can't get them to post! I will try pics again in another post.

Northwoodslakes

Here's 2 pics of my Furnace

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Northwoodslakes

OK guys I know it looks bad and a bit rusty inside. An elderly woman who died there, owned this House before me and most likely didn't know much, you know; but anyhow It seems the Furnace Humidifier was leaking a little bit and I assume that's how some water got inside the Unit over the years. But all is fine, been using it now for 3 Winters. Look at Burner pic, Sharpie written: Unit install 10/5/1993.

Northwoodslakes

Another pic oFurnace 8.2012 (16).jpgf Control Board

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beenthere

The 2 wires from the outdoor unit, 1 should go to Y, and the other should go to the C terminal.

Does the error code legend say that 6 flashes is a flame failure error.

how

My memory for the 50A50A -112 is the 6 flash is reversed polarity or a bad ground.

Any chance that the new transformer wiring you changed has now reversed the polarity??

Also check any furnace ground connections back to the main panel.

Northwoodslakes

The error code on the door only goes up to 5 flashes on my Model.
I remember reading somewhere that 6 flashes had something to do with grounding?
So OK, I have the outside unit wired up to Y & C terminals.
The AC works fine, now only if I can get the damn Burners to stay on!

beenthere

Reverse the yellow and blue wires on the transformer.

Northwoodslakes

You know I have even tried to pull the wires on and off ever which way on the new Transformer I installed, and this didn't seem to even affect anything? Everything else about the furnace wiring has remained the same. How do I check this as you suggest? I'm learning..

beenthere

Ned to open the panel box and check the ground from the furnace to make sure its tight, may also need to check the panel boxes ground.

Did the old transformer have one of its terminals connected to the furnace frame.

how

Looks like there has been some rewiring there. The high voltage side of your transformer looks like both the 120V and the neutral lines are black. Is one of those lines connected to a neutral???

Is the green ground line connected to the 50A50A-112 well connected on both ends?? Can you do a continuity test on that line and connections?

Northwoodslakes

Gentlemen, thanks for all the suggestions, but Nada, nothing. I even took off the new Transformer and looked at the foot. It was coated with like a plastic film or something, so I took some Emery cloth and sanded that down to bare metal, (like my old one was.) But still absolutely No difference.
I will attach a few pics I took of the transformer and the wiring diagram I made, showing how I have it wired. I've tried switching wires, 120V common and hot sides, and the 24V side as well. But nothing has helped.

What is your Opinion on the fact that all the Burners stay on SO MUCH LONGER, 5-6 seconds at least before Flame out. Then I attach the Sensor wire and the Burners only light for like 1 second! Why is this? Is this telling me anything?

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Northwoodslakes

120V Power is Black and Common is White Wire, both ends connected well Transformer/Control Unit.
Yes green is good. It is attached/grounded to the frame that hangs the Blower. I also sanded this electrical eyelet connection, plus I even took an alligator clip and extended the ground to a copper water pipe (close by feeding my Water Heater.) I will check to make sure the other end (the plug connector) is not loose.

Can you please briefly explain how to do a Continuity test? Yeah, I do have a meter with the 2 wire probes, but need you to explain if it isn't too involved? I Am learning from you guys!
I just don't understand it, my AC unit works just fine thru the Control Unit, yet I always have Burner flame out when turning the on the Heat..
This Furnace worked just fine until I put in the new transformer. I burnt up the old one screwing around with the Thermostat terminal connections with a jumper wire like a Dummy, but after the smell I figured I burnt-up the Transformer. I Bought a new one on Ebay and all was fine. AC works perfect, but not Heating. I mean the 120V / 24V transformer must not be bad if it is working when I turn the AC on? This new Transformer has a 40v rating, (the old one had a 30V rating). I could not find the exact replacement and I was told this one would work fine. It is pretty much looks/mounts the same in every other way. This would have nothing to do with the Burners?

Northwoodslakes

Man, I've reversed all 4 transformer wires every which way on the Transformer and the Burners always behave the same way like I said. Flame Out!