Bad honeywell valve?

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Great thread! Had intermittent problems with the unit not lighting off. When I wiggled the four wire connector at the gas valve, it would light. Found this site and re-soldered the connection for the relay on the circuit board. Unit works fine! You need a T-15 Tamper Proof TORX bit ($5.99 @ Harbor Freight Tools) to take the cover off (not a T-10 listed above). This was on a Honeywell SV9500M 2682 gas valve.
 
Hello all, I am facing the same issue, my tech checked it and say that the ignitor is working fine and the computer board is good too, he see the pilot turning on but the gas valve is not opening. After reading all these posts I asked him if there could be a loose connection and if he checked the harness but he is saying that I need to replace the valve and there is no loose connection. He used the voltage meter and he says he is getting 24 volt out of the gas valve... My question is if those soldered connections are bad or my wiring harness is also loose as most of the posters here had found out, would he still get the 24 volt out of the gas valve? or should I try something like you all have tried before spending $200 on a new gas valve and the labor to put it in? Thanks
 
is there is a sensor attached to the ignitor or the gas valve? Now my tech is saying that the sensor might be dirty and that is why it sometimes does not work. He ran into the similar problem somewhere else and cleaned the sensor that had some gas residue and managed to get it fixed? I have asked him to come over but his schedule is pretty much full but he says he will try t be here today.
In the meantime, is it something I could look into? where is this sensor located? any thoughts? It is also very likely that he probably had the same issue with loose connections and while taking things apart, he might have fixed that problem unknowingly... perhaps.
 
. . .and there is no loose connection.
He can check connection integrity while current is flowing.
For relay contacts while rated current if flowing, less than 30 mV voltage drop due to contact impedance is good and more than 100 mV is bad.
For a Wirenut carrying 10A, 50 mV is way too much and means it was improperly installed. A good install shows much less drop.

I'd think these numbers would be smaller for a connection that uses tempered spring steel like in your HVAC stuff. The makers of these fasteners may give you pass/fail factory data by their QC people.
 
Thanks Wuzzat.. The tech came in and he tried to clean the sensor next to the ignitor, check few more sensors, confirmed that the gas is actually coming through the gas valve for the small ignitor but there is not gas supply to the bigger pipe going towards the flame.
He does not read these forums so it was hard for me to convince him to open the gas valve beige cover that is attached using couple of either Allen Key or star screws.
His final conclusion is just change the valve, Should I at least try to take the plastic beige piece and see if the problem is same as other fellow posters have described earlier? If I have some photos that would have been a big help. Cheers!
 
His final conclusion is just change the valve
Not many people in the US say "cheers". :p

Ask him how sure he is.
If he is 90% sure it's the valve and the valve costs $X then he should refund you 0.9 of $X if he is wrong!

Ha! Have him put his money where his mouth is.
 
Boonstra's one hour service just tried to rape me for $910 to replace this valve in my heil furnace. When I phoned Amre supply they quoted me $250 for the valve. I dont mind paying for service or some markup on parts but that is outrageous! Graham Hartwell, Stoney Ontario
 
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IF you want to repair the valve. (you assume all liability) remove the two small security tor screws holding the brown plastic cover on. we are only removing the half with the knob on/off knob sticking up through it. gently move the cover around a little and it should just lift off. now look close at the solder connections on the circut board. specifically at the area where the 4 wire main plug is connected. look for a crack around 1 pin ( or even a burn mark) Resolder this connetion using a radio shack silver bearing solder or equivalent, to give it a little more strength. Put the cover & screws back on & youre finished.
 
The advice given here is right on. I had the same problem and was able to fix it in five minutes. As soon as I took off the cover (good tip about buying the correct torx bits at Harbor Freight), I saw a bad solder connection. Resoldered and put it back together, reinstalled and it worked as it should. Since the valve kind of hung out there unsupported, I put a wood 2x2 under it and also padded the place where the gas line came in. I hope that will keep it from vibrating and breaking more solder joints.
 
I was relieved to see that I wasn't the only one...today, after holding the wire harness horizonally (the one that goes to "ignitor" on the module) it stopped working altogether. After jiggling and pushing even harder, I was able to get it to work. But only once. I am looking for any advice on this, but I think the only thing to do is replace the SV9500M unit :( Thank you to everyone who shared I'm glad I'm not the only person rigging up wires in my furnace!
 
I was relieved to see that I wasn't the only one having this ignition issue...so firstly a big thank you to everyone on here that's posted their stories. Today, after holding the wire harness horizonally for months (the one that goes to "ignitor" on the module) it stopped working altogether. After jiggling and pushing even harder, I was able to get it to work one time so we didn't freeze. Next step is to take it apart and look for the bad connections, fortunately I'm a electro-mechanical engineer so I know what to look for. I will post instructions if I get this to work like others did! Thank you again for all of the advise...to be continued. I'm glad I'm not the only person McGyvering up my furnace!! :)
 
As in the previous posts, I had the same symptoms you did. I removed the cover (T-15 security screws) and saw two soldered joints that had seperated from the board. Used a soldering iron to re-melt the solder to form a solid connection. It has been two and a half years and still working fine.

There is a video on youtube on this:

[ame]http://www.youtube.com/watch?v=HUBvnhhZK2Q[/ame]
 
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