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IMPCO Technologies Gas Valve Defect on Propane Vapor Line


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Old 02-26-2017, 05:12:44 PM
JohnnyC JohnnyC is offline
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Default IMPCO Technologies Gas Valve Defect on Propane Vapor Line

IMPCO Technologies Gas Valve Defect on Propane Vapor Line -

JohnnyC almost blew his azz up this afternoon while running an Onan 6.5NH on propane. The problem was an defective IMPCO Technologies Gas Valve. I was exercising the 6.5NH for 45 minutes. About 10 minutes into the exercise I smelled something funny burning. I knew it was not the actual 6.5NH's motor or generator head and thought is was only one of the electric heaters used to load the 6.5NH.

I went left my garage during most of the 45 minute generator exercise. When I returned to the garage I still smelled the burning and now it was very strong. When looking at the 6.5NH I seen smoke coming from the electric IMPCO gas shutoff valve as it was melting in front of me. I immediately shut down the generator and assured myself that all was secured as I wonder WTF went wrong??? I immediately thought that the generator was feeding the electric gas valve solenoid more than ~12 vdc. I restarted the generator with the valve's electric solenoid hooked up and took a voltage reading and it was slightly less than 14 vdc which is perfectly good. As this point, I can only assume the valve is defective. I bought the valve last year and does not have more than 4 hours of use on it.

Could there have been a possibility that a fire could have resulted if I did not catch the problem? Vapor gas runs directly below the point that was burning.

The video:
https://www.youtube.com/watch?v=JeqN...ature=youtu.be

Beware if you use this safety valve on your generator. Vapor gas passes directly through the line below the coil and is only regulated at that point by your fuel source regulator with no safety shutoff. If the coil caught fire, it could result in an uncontrolled fire or explosion.

JohnnyC
New Jersey
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Old 02-26-2017, 05:33:51 PM
Vanman Vanman is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Huh. Well that's not very nice. Can see the coil catching fire, but not causing any other trouble unless it burned through the rubber gas hose. That wouldn't be good lol.

Coil might be defective- shorted turns.

Also some 12 volt coils are not rated for 14 volts. And some are not rated for continuous duty. All things to verify when you shop for the replacement.
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Old 02-26-2017, 05:37:59 PM
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Motorhead Motorhead is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

The coil alone is replaceable. Not good JU-JU!
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Old 02-26-2017, 05:44:59 PM
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Jim McIntyre Jim McIntyre is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Where'd you buy that valve?
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Old 02-26-2017, 05:54:49 PM
JohnnyC JohnnyC is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Quote:
Originally Posted by Jim McIntyre View Post
Where'd you buy that valve?
I bought it online. I have the receipt somewhere in a stack of papers for the 6.5... I got 3 of these valves and only this one seems to be defective.

I think I had enough Onan therapy for the weekend.

JohnnyC
New Jersey
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Old 02-26-2017, 06:14:18 PM
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Jim McIntyre Jim McIntyre is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Just curious if it's an authentic IMPCO from an authorized distributor, or an 'IMPCO-Style' valve from who-knows-where?
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Old 02-26-2017, 07:43:51 PM
Ray Lynch Ray Lynch is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Johnny
You said in your JB thread that you hooked up the transfer switch that came with your JB to your NH and strange things were happening.
Could this be related to your gas valve failure?
Ray
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Old 02-26-2017, 07:49:32 PM
JohnnyC JohnnyC is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Quote:
Originally Posted by Jim McIntyre View Post
Just curious if it's an authentic IMPCO from an authorized distributor, or an 'IMPCO-Style' valve from who-knows-where?
You raised a very good question. When I read your response on my cell I was 15 miles away from home. I came right home to see if it was a Chinese p.o.s. Well, it is the real deal. You can see the "IMPCO" name embossed in the casting of the valve in the first picture below. In the same picture I show that the short was not the voltage lead wires. They are in excellent condition as seen to the far left in the first picture. What you see to the far right in the first picture is the valve without the burned coil. No damage.

The second set of pictures show the damage to the coil. I had to chop away the melted blob between the wire connector and the body of the coil as seen in the far left of the picture. The middle shows the melted blob looking down. To the far right show the coil and without doubt something that happened inside the coil is the cause of the problem.

These valves are highly rated. WTFH?? (for us older folks, WTFH means What The F--- Happened???)

JohnnyC
New Jersey
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Old 02-26-2017, 08:06:37 PM
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

It would be interesting to measure the resistance of the defective coil and compare to that of the two good ones that you have.
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Old 02-26-2017, 08:18:20 PM
JohnnyC JohnnyC is offline
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Default Re: IMPCO Technologies Gas Valve Defect on Propane Vapor Line

Quote:
Originally Posted by Ray Lynch View Post
Johnny
You said in your JB thread that you hooked up the transfer switch that came with your JB to your NH and strange things were happening.
Could this be related to your gas valve failure?
Ray
I disconnected the transfer switch from the NH shortly after I realized I needed to figure more about the switch. The NH was running on it's own for awhile when the coil burned up. If for some reason I momentarily fed back utility voltage into the NH's 12vdc circuit to initially start the problem, I think there would be lots more damage.

JohgnnyC
New Jersey
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