Pilot light is on, burners won't light
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Pilot light is on, burners won't light
I have an older rheem natural gas furnace. Model no. RGLA-07EA-CR
serial no. GN3D206 F2087 9603
The furnace completely turned off yesterday. I have been able to get the pilot light back on, however the furnace still will not fire up the main burners and work. The thermostat is calling for heat, but the furnaces never turns on.
I tried to upload some pictures of the unit, but can't seem to get them to upload from my iPhone.
I have a general ability with just about everything, understand and know how to use a multimeter. Is anyone able to help me get the furnace running?
It's not the breaker or the fuse
serial no. GN3D206 F2087 9603
The furnace completely turned off yesterday. I have been able to get the pilot light back on, however the furnace still will not fire up the main burners and work. The thermostat is calling for heat, but the furnaces never turns on.
I tried to upload some pictures of the unit, but can't seem to get them to upload from my iPhone.
I have a general ability with just about everything, understand and know how to use a multimeter. Is anyone able to help me get the furnace running?
It's not the breaker or the fuse
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The pilot light is working and looks normal.. It seems that the unit is not reciving the call for heat. It seems as though the power from the thermostat is not making it to the unit. I'm not reading any volts anywhere inside the unit.
#6
Have you checked and reset the circuit breaker or fuse feeding the furnace?
If there is power to the furnace, check input and output of transformer. 120 volts in and 24 volts out - both AC.
If there is power to the furnace, check input and output of transformer. 120 volts in and 24 volts out - both AC.
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Yes I have checked and red checked the breaker and fuse. I've got 120 on the outside of the unit, not finding any stable reading inside.
The thermostat clicks when the set point is higher then the room temp, but nothing happens within the unit.
The thermostat clicks when the set point is higher then the room temp, but nothing happens within the unit.
#8
1. Check the low voltage fuse inside the furnace - usually located in the blower compartment.
2. remove the t-stat and jumper R and W to bypass it
3. Check all safeties for continuity with power off - fan/limit (limit side as labelled), vent safety switch if there is one (located on the side of the draft), rollout switch if there is one.
2. remove the t-stat and jumper R and W to bypass it
3. Check all safeties for continuity with power off - fan/limit (limit side as labelled), vent safety switch if there is one (located on the side of the draft), rollout switch if there is one.
#9
Ooops I mistook the red wire for a high voltage igniter wire. I see you have a thermocouple safety. Check up by the draft hood for a manual reset limit, some Rheems have one.. Also have yo taken a volt read at the gas valve terminals with the thermostat calling for heat.
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Confirm, with your meter, there are 24 volts between red & white at the thermostat. If not, go back to the furnace, locate the transformer & measure the secondary side of it. There should be 24 volts there. If there is, we have a problem somwhere between the transformer & stat. If no 24 at the transformer, confirm 120v on the primary side.
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I just wanted to confirm, I'm going to pull my thermostat off and place the positive multimeter probe to the red and the negative to black.
It's probably time I have an expert come and fix things.
I was told by a repair service that usually this is the thermocouple has gone. I am going to replace it tonight and hope to jebus that it fires up
It's probably time I have an expert come and fix things.
I was told by a repair service that usually this is the thermocouple has gone. I am going to replace it tonight and hope to jebus that it fires up
#13
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Since you have a pilot take a wire or needle nose pliers and jump across the terminals on the gas valve. Since you have a pilot and it's 24v it's no dangerous. If it lights the gas valve is fine and it's not getting the signal. If you think it's your t-stat check for 24v. With the t-stat removed you can jump the terminals with no danger to see if it comes on. If it does replace t-stat. If it doesn't and you get 24v make sure your thermocouple has a good flame. Make sure all connections are tight and safety's are reset if you have any.
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If the pilot stays lit, it's not the thermocouple. All the thermocouple does is power the pilot side of the gas valve, nothing more.
If you have red & black to the thermostat instead of the "normal' red & white, yes, check for 24 volts between black & red. Since we are looking for AC voltage, it matters not which probe goes to which wire.
If you have red & black to the thermostat instead of the "normal' red & white, yes, check for 24 volts between black & red. Since we are looking for AC voltage, it matters not which probe goes to which wire.
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After following wires and testing continueity, I found that a safety switch had gone out. Replaced switch and furnace works. Thanks for all the help on this one guys.. I learned quite a bit.
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Good job in finding the bad safety. We would have gotten there eventually. It's tough trying to help someone online when you don't know how skilled they are in tracing circuits, etc.
Congrats on the fix. Let's hope it was due to an old switch & nothing wrong with the furnace causing the safety to open repeatedly.
Congrats on the fix. Let's hope it was due to an old switch & nothing wrong with the furnace causing the safety to open repeatedly.
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Ok so my system is natural gas and the water boiler has a pilot light but the burner does not turn on. There are no safety switches and looks like all electronics are in blower box on top unit.
Pilot flame is blue when t-stat is raised pilot flame gets a little bigger and some orange in color.
I looked in the burner area and saw a chunk of metal sitting on it. Pic attach. Looked like it came from within the boiler
Pilot flame is blue when t-stat is raised pilot flame gets a little bigger and some orange in color.
I looked in the burner area and saw a chunk of metal sitting on it. Pic attach. Looked like it came from within the boiler
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I suggest you call a qualified plumber to determine from where that part came. It certainly looks flame has been hitting it. I suspect you are going to have to have a new water heater but without knowing what that burned part is, that is little more than a guess.
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I am djpardi's brother, and co-owner of the property with the water heater he posted about.
We've determined that part to be the bottom of the flue baffle. We are looking into ordering a replacement part through the manufacturer to replace, but our main concern at this point is why did this happen and will it happen again?
The water heater is a 75 gallon American Powerflex (Powervent) model number PVG62-75T75-3NOV shown here: Product Details - Products
It is supplying hot water to a 3-family home with a total of 4 people. Is it being overused which is causing it to melt away the bottom of the flue baffle??
We assume best case scenario with the old flue baffle with severed bottom piece it will just run less efficiently, and worst case could possibly be a fire hazard?
Any thoughts on the matter are appreciated.
[EDIT] Here's a diagram showing the flue baffle part running down the middle of the unit:
We've determined that part to be the bottom of the flue baffle. We are looking into ordering a replacement part through the manufacturer to replace, but our main concern at this point is why did this happen and will it happen again?
The water heater is a 75 gallon American Powerflex (Powervent) model number PVG62-75T75-3NOV shown here: Product Details - Products
It is supplying hot water to a 3-family home with a total of 4 people. Is it being overused which is causing it to melt away the bottom of the flue baffle??
We assume best case scenario with the old flue baffle with severed bottom piece it will just run less efficiently, and worst case could possibly be a fire hazard?
Any thoughts on the matter are appreciated.
[EDIT] Here's a diagram showing the flue baffle part running down the middle of the unit:

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Also, I noticed the original post here is for a furnace, not a water heater, and my brother probably should have started a new thread.
Please let me know if it would be more appropriate to do so.
[EDIT] I started a new thread here: http://www.doityourself.com/forum/wa...ml#post2251822
Please let me know if it would be more appropriate to do so.
[EDIT] I started a new thread here: http://www.doityourself.com/forum/wa...ml#post2251822
Last edited by tmpardi77; 03-25-14 at 09:18 AM.