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Rick
Rick, HVAC Supervisor
Category: HVAC
Satisfied Customers: 20091
Experience:  40+ yrs. experience as a licensed oil & gas technician.
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I have a Janitrol Furnace. The furnace quit and I called the

Customer Question

I have a Janitrol Furnace. The furnace quit and I called the Furnace company to fix it. They said the gas valve was bad and installed a new Honeywell Valve VR8345M4302. It worked for a few days and quit again. They checked and said that the valve was defective. they replaced it and it still won't work. It powers up,goes thru the sequence normally then when the valve comes on, It only stays for 4 to 5 seconds and then shuts down. When a voltmeter attached I have 24 Vac to the valve that stays on for 12 to 15 Sec. until it figures oust there is no flame. No blinky codes.
Now they say that the tubes that the Gas travels through are bad. The parts are no longer available and I have to have them install a new furnace. It operates on LP and has a new cntrol board installed last fall. Any ideas. The Furnace guy says he changed the spring in the valve and the input and outputs readings are normal are normal. (10)
for Propane. The gas company checked the regulator output at the pant also 10 OK
Any ideas??? Maybe the wrong valve for this application
Submitted: 9 months ago.
Category: HVAC
Expert:  Rick replied 9 months ago.
What is the model number of your furnace?
Customer: replied 9 months ago.
Hi Rick, I am at my office and I don't have it with me. I will get it tonight for you.
Expert:  Rick replied 9 months ago.
I'm online usually until about 7 pm EDT. Do any of the burners light?
Customer: replied 9 months ago.
HI RickThe burners come on normally for 1 or 2 secs. then shut down. Sometimes the flame will go over to the 2 burner, but it never makes it to the third, where the flame sensor is located. There are 3 burners. The model number is ***** Serial No. is (###) ###-#### ***** is a Janitrol about 20 yrs old.ED
Customer: replied 9 months ago.
Since I continue to have 24VAC at the valve after shut down for about 10 to12 secs. Then it faults out and the blink code comes on indicating the flame sensor is causing the problem.
Expert:  Rick replied 9 months ago.
I'm online usually until about 7 pm EDT. Do any of the burners light?
Expert:  Rick replied 9 months ago.
I just noticed your previous post. Since the flame never makes to the last burner the unit will shut down on a flame rectification failure. Sounds like a problem with the crossovers like your guys said but usually all it takes is cleaning them out.
Expert:  Rick replied 9 months ago.
Ok, I just found what looks like replacement burners for your model. I'd call these guys to verify.http://www.repairclinic.com/PartDetail/Goodman-Furnace-Burner-Tube/B4022700/2646068?modelNumber=GMPN060-3&ss=a36b377d1443084&mr=1
Customer: replied 9 months ago.
I have already bought the tubes. they are the same numbers that you came up with. I will change them out and we will see
I just didn't want to pull out the burner assembly if I have the wrong valve in the beast, then have to pull it again to change the valve. All I meant is that the flame shuts down before it can get to the last tube. 2 secs max. With the volt meter showing that the control thinks the valve is on the voltage stays on about 8 to 10 secs. The flame is gone long before the control shuts the voltage off. Most of the time it just puffs and is out. I believe that there is something wrong with the valve or it is a newer kind of valve or it is not set right.
Expert:  Rick replied 9 months ago.
There's no way I can know if they messed up the conversion. I assume they converted the valve from NG to LP since replacement valve usually come set up for NG. Did they check the manifold pressure after installing the valve? You'll need a gauge that reads in inches WC (water column) to check the manifold pressure.
Expert:  Rick replied 9 months ago.
Manifold pressure should be 9.5" to 10.5" WC. Supply pressure should be 11" to 13" WC
Expert:  Rick replied 9 months ago.
I'm logging off for the night. If you have more questions I'll respond in the morning. If not I'd appreciate a favorable rating
Customer: replied 9 months ago.
Its getting late here too. The gas company came out and checked the tank and regulators on Friday. They said everything of their is OK. The pressure at the last regulator is 10. Also the pressure the inlet of the valve is also 10. On the first valve they put in after it quit working the pressure checked 3.5 on the output side.. That is why he said the first new valve was defective. On the second new valve,. I didn't hear what they said it was. I guess it was OK, so they went after the regulator by the tank,
when that was OK they decided it was the tubes. The gas company guy told me that the tubes couldn't cause this problem.
I will put in the new tubes tomorrow and we will see, I guess.
Expert:  Rick replied 9 months ago.
10 (assuming 10" WC) is too low for propane supply pressure which should be 11 to 13. 3.5 is NG manifold pressure. LP manifold pressure should be 9.5" WC to 10.5" WC. Until/unless you know the manifold pressure you can't be sure the gas valve is set properly.

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