Dare I fix a gas valve?

[reader2580]

The gas valve on my Kohler Standby generator leaks gas and the generator was red tagged. I took the gas valve apart today and it had some corrosion on the seat. I cleaned up the seat and put it back together. I did not turn the gas back on. Gas was leaking where it enter the carb so I can't exactly just spray soapy water to test.

Do I dare try to use a gas valve I repaired, or should I just buy a new valve for $85? I don't have a problem buying a new valve for $85. My problem is not wanting to spend $200 to $300 for an HVAC company to come out and replace the valve. I wouldn't have the slightest clue how get the valve out since there is no union in the black pipe.

 

[kd3pc]

given your comments....red tagged by someone.....get the experts out for the repair.

Some gas valves are not user repairable, ie they require some skill and test gear to set correctly..let alone operate.

Gas leaking in to the carb...may or may not (likely a problem not related to the valve) be solved with your repair.

get an expert .

 

[The Cobbler]

if there's gas leaking at the carb I think it's faulty .oh wait, it was leaking but now you're not sure?
I cleaned one as you have and had good results, but I did it more to seee if the generator would start, I didn't leave it hooked up. (never got around to doing anymore with it yet. )
there are rebuild kits available for some of the valves. a new valve should be relatively easy to install but I'm not ure about any adjustment on them

 

[reader2580]

given your comments....red tagged by someone.....get the experts out for the repair.

I was smelling gas near the generator on a day with no wind. The generator is five feet from the meter so I called the gas company to see if the meter was leaking and they found leak at the carb in the generator.

I don't know how natural gas could even be getting to the carb if the gas valve is not leaking. Maybe the gas valve is easy to replace, but not being a plumber I have no idea how to take the pipes apart. I'll have to call the HVAC company.

 

[reader2580]

if there's gas leaking at the carb I think it's faulty .oh wait, it was leaking but now you're not sure?
I cleaned one as you have and had good results, but I did it more to seee if the generator would start, I didn't leave it hooked up. (never got around to doing anymore with it yet. )
there are rebuild kits available for some of the valves. a new valve should be relatively easy to install but I'm not ure about any adjustment on them

The generator starts and run just fine. It is leaking gas when it is not running unless I turn off the manual shutoff.

This valve is cheap enough to not even try to rebuild it if a rebuild is even possible. The seat cannot be replaced by the looks of it. There is just a rubber flap that sits on top of the seat.

Valve is a BASO H91JV-1. It is a 12 volt gas valve.

 

[CNGsaves]

For that amount, I'd suggest replacing with new valve.

Good thing you're running NG as it's lighter than air and gets blown away with the wind. If you had LPG, that leak would have pooled propane near the ground (or inside the genset enclosure) and would have been quite dangerous.

 

[brewchief]

Pics of the gas lines near the generator will show how it comes apart, there has to be a union someplace even if it doesn't look like a union.

 

[James-W]

There are times when it is best to bite the bullet and have a qualified technician do the job.

 

[bacr619]

This valves are not rebuildable. It needs to be replaced.

Sent from my SAMSUNG-SM-J320A using Tapatalk

 

[eddieK]

Gas valves are not built to repair. That is $85.00 well spent verses not spending $85.00 and it costing you a whole lot more.

 

[bacr619]

Gas valves are not built to repair. That is $85.00 well spent verses not spending $85.00 and it costing you a whole lot more.

10-4 that.

Sent from my SAMSUNG-SM-J320A using Tapatalk

 

[Swingpress]

**NEVER DO THIS!** Just had to add that for my own conscience.

Just as an aside because it jogged my memory! When I was younger I remember a welder being flown out to a site when my fathers construction company hit a very large high pressure gas line with an excavator, as the operator was told it was much shallower than the target dig depth. Apparently they couldn't shut off the flow but only slow it down. He asked my father which piece of equipment he liked the least and used it to lay in a new section of pipe and proceeded to WELD it in place!!! Talk about nerve racking! And expensive!

 

[reader2580]

Gas valves are not built to repair. That is $85.00 well spent verses not spending $85.00 and it costing you a whole lot more.

I will replace it, but it will cost a whole lot more than $85 to replace it. I will have to call out an HVAC company to take the plumbing apart at a cost of $200 to $300 for the call and labor. There is no union the way the HVAC ran the gas to the unit.

 

[EOC_Jason]

I would like to see pictures of the gas line. How did they not use a union?

 

[reader2580]

I will try to get a picture this evening. There was a threaded stub sticking out of the generator. The HVAC company put a 90 on there and then ran a short stub over to a new regulator. There is no union between the gas valve and the new 90. I had really expected the HVAC company to replace everything up to the gas valve, but I never specifically requested that.

 

[derkperk]

You must be able to break the pipe back to some where. It could not be installed threaded without one. May not be between the valve and the 90

Sent from my XT1565 using Tapatalk

 

[malibu101]

You must be able to break the pipe back to some where. It could not be installed threaded without one. May not be between the valve and the 90

Sent from my XT1565 using Tapatalk

Exactly. It was put together so it has to come apart.

Or just put a wrench on the pipe to hold it and spin the generator around.

Pictures would really help.

 

[reader2580]

The only way I know to get it apart would be to disconnect the copper from the regulator and then spin the entire assembly around to remove the pipe from the gas valve. I don't really want to do my own gas work anyhow.

 

[reader2580]

Finally took pictures.

 

[derkperk]

Your union is the brass flare nut that connects the copper tubing to the galvanized T. You'll have to break the pipe back to the gas valve from there.

I've never seen a Y strainer on a gas line...

Sent from my XT1565 using Tapatalk

 

[malibu101]

Your union is the brass flare nut that connects the copper tubing to the galvanized T. You'll have to break the pipe back to the gas valve from there.

I've never seen a Y strainer on a gas line...

Sent from my XT1565 using Tapatalk

Yes.
You have to take apart more than 1 connection, but this is your starting place.
The battery probably has to come out to make room to swing the regulator around.

 

[derkperk]

Don't forget Lefty loosey.

Sent from my XT1565 using Tapatalk

 

[malibu101]

Don't forget Lefty loosey.

Sent from my XT1565 using Tapatalk

Yeah, I just noticed that after my reply.

Maybe the side panel has to come off to remove the regulator?
Things may not always be as easy as unscrewing something whithout removing something else to make room to unscrew the offending part.

 

[derkperk]

Yeah, I just noticed that after my reply.

Maybe the side panel has to come off to remove the regulator?
Things may not always be as easy as unscrewing something whithout removing something else to make room to unscrew the offending part.

The way I see it is that large reg is down stream the gas valve...Gas flow from right to left.

Sent from my XT1565 using Tapatalk

 

[mm08822]

Since you have a NG leak and looking at the general condition of the black pipe and fittings, I would recommend you take that entire gas train apart and re-do it all. The generator is not critical and the weather is moderating so you can have it out of service for a short time.

Most fittings and ******* can be re-used. Some can be eliminated and replaced with longer *******. Use the largest size fittings for as long as you can until you are forced to reduce size b/c of a device’s port size. Dis-assemble, clean all threads w/wire wheel, and start to re-assemble with new pipe dope. Also see if any excessive rust inside – wire brush it out if needed.

If your gas valve is leaking then you can replace it. See the Basotrol links below. I would buy a new one with the same size ports as the generator’s regulator – no need to mess with extra reducers. Also check the generator’s regulator. The diaphragm may be leaking and you could be smelling gas from it. Mfr looks to be Garretson, model KN. See link below for mfr. They make a rebuild kits. Now would be a good time for that too.

I would get rid of that wye strainer. I’ve never seen one of those in a NG application. Not even sure it is rated for NG use. Has it ever been opened to check the amount of debris in the strainer?
Add a union after the gas valve (upstream) inside the enclosure.
I would make provisions for a test port after the gas valve (¼” npt) inside the unit and plug it. (Unless there is already one available.)

On the outside wall of the unit, I would add a pipe strap and standoff to support the regulator, sediment trap and copper tubing connection. It should not be hanging free like it is now.

All of this can be leak tested with liquid soap before running the unit and as you run it.

Paint all of the pipe and fittings with enamel paint – inside and out of the generator enclosure after leak testing. Otherwise it will all rust again.

http://www.baso.com/lib/subdomain/b...ries_Automatic_Gas_Valve_Product_Bulletin.pdf
http://www.baso.com/lib/subdomain/b...utoff_Gas_Valve_Installation_Instructions.pdf
http://www.baso.com/lib/subdomain/b...ement_magnetic_operators_application_note.pdf
http://reader.mediawiremobile.com/BASO/issues/200090/viewer?page=8
https://www.propanecarbs.com/garretson/garretson_kn_demand_regulator.html

 

[EOC_Jason]

I would have to concur... The drip leg outside is good, but the tee & the strainer on the inside... I would use one piece to go from that sensor or whatever it is to the outside of the generator.

 

[reader2580]

How could the regulator after the gas valve be leaking when the gas valve is off?

No way am I going to try to work on natural gas. I will have to hire someone.

 

[CNGsaves]

Damn . . . . who installed all that mish-mash of NG pieces ??

Looks like some of those pieces of pipe are 50+ years old ???!!!!

+1 to just re-do it all from scratch.

Be sure to add a Shut-Off valve just outside the house.

 

[reader2580]

There is a shutoff valve at the house already.

My guess is the gas pipes inside the generator housing are about 25 years old. I had expected the HVAC company to replace all pipe when they installed the gas line last year, but I wasn't specific that I wanted all the pipe replaced.

 

[CNGsaves]

Oh, I thought you just got the generator last year . . ie for first time ??

The shutoff should be near the outside of house . . BEFORE . . the other stuff going out to generator so you can isolate all that outside stuff. If something goes wrong (ie massive leak), you want quick and easy way to shut off the flow of NG. Also, this would make working on genset NG piping so much easier and safer.

 

[mm08822]

There is a shutoff valve at the house already.

My guess is the gas pipes inside the generator housing are about 25 years old. I had expected the HVAC company to replace all pipe when they installed the gas line last year, but I wasn't specific that I wanted all the pipe replaced.

So with the generator 25 yrs old, rebuilding the gas regulator is a good idea since the diaphragm could be very brittle. If you are disassembling that gas train, now is the time to do it. I also assume you were referring to the generator internal regulator where you originally mentioned carb. You may also want to look at what is after the regulator further on in the generator.

If you own 2 pipe wrenches, can screw nuts onto bolts, blow bubbles, finger paint, then you can do the gas line. It is not cyanide nor tnt. That is why you leak test it and the gas has a rotten egg odorizer in it for early detection.

If you still feel this is way beyond your comfort zone/capability, call a plumber and loose that hvac guy. Anyone who let that 25 yr old stuff stay as is, i wouldn't be calling back. Have the plumber replace/rework all that stuff.

 

[reader2580]

The tech from the gas company who came out specifically said it was leaking gas from the air box holding the air filter just above the carb on the engine.

My concern with DIY is two fold. First, soapy water is not going to work to detect if natural gas is still leaking at the air box. Second, I don't have the slightest idea how to measure black pipe so I could have a pipe cut and threaded the right length.

I like to do as much as I can DIY, but I think gas is one thing I will pay for. The HVAC company I used has glowing reviews on Angie's List, but I didn't use Angie's List to select them. There are 200+ other HVAC companies in the area so I could easily find another one. I typically have dealt with a different HVAC company, but they are 20 miles away so I tried someone only a few miles away for this job. I could also call a plumber as they work with gas for water heaters.

I found a picture of the rest of the gas pipe installation. They ran the copper pipe right along the side of the electrical conduit.

 

[reader2580]

I would have preferred that copper be run all the way to the gas valve. I had this exact same model generator in my previous house and that is the way the HVAC guys did it there. However, the HVAC company for my current house said I needed the extra regulator because I have high pressure gas.

It appears that either black or galvanized pipe is allowed for gas although some worry that the zinc on galvanized can flake off and plug orfices.

 

[mm08822]

The tech from the gas company who came out specifically said it was leaking gas from the air box holding the air filter just above the carb on the engine.

My concern with DIY is two fold. First, soapy water is not going to work to detect if natural gas is still leaking at the air box. Second, I don't have the slightest idea how to measure black pipe so I could have a pipe cut and threaded the right length.

I like to do as much as I can DIY, but I think gas is one thing I will pay for. The HVAC company I used has glowing reviews on Angie's List, but I didn't use Angie's List to select them. There are 200+ other HVAC companies in the area so I could easily find another one. I typically have dealt with a different HVAC company, but they are 20 miles away so I tried someone only a few miles away for this job. I could also call a plumber as they work with gas for water heaters.

Then I would see what parts you need around that air box and order them so they are available for change out during the rest of the job. Also buy the gas valve and a regulator rebuild kit (or a brandy new one.)

Whoever you call out is not going to have those parts on hand, so it is at least 2 trip trips to get this done $$.

Your job is really not that difficult to do. Buy the parts you need, measure what is there and buy a few ******* of various lengths to finish off the line inside the gen to the 90 on the outside. Also whatever fittings you need. Worst case you tell Wally at home depot I need a pipe/****** x inches plus allowance for threads. Lay it all out and if you're missing something put on the list for the next home depot run. Wally will hook you up. Buy extra and return leftovers.

A plumber is just going to rip all that stuff out and replace with new. You however could take a few minutes and refurbish those pieces.

 

[reader2580]

Then I would see what parts you need around that air box and order them so they are available for change out during the rest of the job. Also buy the gas valve and a regulator rebuild kit (or a brandy new one.)

Whoever you call out is not going to have those parts on hand, so it is at least 2 trip trips to get this done $$.

I don't think there is anything to fix or replace at the air box. I think the gas that is getting through the gas valve is simply exiting at the air box. It is not leaking right now because the shutoff valve at the meter is turned off.

I will give any repair person the photos of the part numbers in advance so they can get the parts before coming out. I could just order the parts, but if they buy them they have to warranty the parts and the labor.

 

[ljhhontx]

I have worked as a gas tech for 25 years and have a lot of questions about your setup. You have a regulator at the meter that has a red cap, that indicates a 2# outlet pressure. Copper tubing is not acceptable for natural gas unless it is tin lined which to my knowledge is no longer available. Regular copper tubing will flake off internally and contaminate your fittings downstream the copper portion, ie black flakes that build up at regulators and orifices possibly causing a valve to leak through due to failure to reseat after opening. I would not be nearly as worried about the external appearance of the iron pipe as I would be the internal appearance of the copper tubing. The copper tubing shown in the photo is also undersized for the application even at 2# pressure.

 

[eddieK]

I would like to see pictures of the gas line. How did they not use a union?

Either started from one end...or installed a left / right ******.

 

[Norcal]

My vote also goes for replacing the valve, should not be that difficult. If that was in Pacific Gas & Electric, PG&E, territory you would get tagged for the copper tubing being used for natural gas.

 

[eddieK]

My vote also goes for replacing the valve, should not be that difficult. If that was in Pacific Gas & Electric, PG&E, territory you would get tagged for the copper tubing being used for natural gas.

I've had a few calls over the years where the leak was the copper flex or piping...the additive that provides the smell deteriorates copper...and I've not once seen a Y installed on natural gas either, it has a drip leg.

Also - It's code here that gas pipe exposed to weather must be galvanized or coated, black iron is not allowed.

 

[reader2580]

Copper is used everywhere for gas here in Minnesota. Every house I have lived in has copper for natural gas. A different HVAC company installed the lines from the meter to all the gas appliances in the house and it is all copper. I know that some areas of the country copper is not allowed because the gas has hydrogen sulfide in it and will eat copper.

I talked to the owner of the HVAC company and told him the generator is rated at 199,000 BTU. He said 1/2" would be fine since I have 2 PSI gas. The 2 PSI service is why they installed an additional regulator.

The gas company came out and checked for leaks and didn't find any leaks on the copper.