More home repair: Gas line disassembly

I have a natural gas fire pit in the patio. The fire pit contains a 24" iron round fire ring. The valve controlling the flow of natural gas to the fire pit is located a few inches under the stone tile floor and I use a regular 3" long key to open and close the valve. The valve rotates open and closed smoothly. Other gas appliances work fine (i.e., water heater, swimming pool heater, BBQ island.)

The initial problem was that the fire ring did not ignite although the valve is wide open. So I removed all of the lava rock above the fire ring to expose it. My first thought was to remove the threaded plug in the center of the fire ring to see if gas was available there. I applied liquid wrench lubricant to the threads, tapped on the plug with a hammer, then tried removing the plug. Although the wrench would rotate the plug, I found that the entire assembly was moving (not just the plug). I assume that the entire vertical section of the gas line is rotating on the elbow beneath it.

Then the fire ring collapsed due to surface corrosion. I had previously confirmed that I could buy a new one, so no worries. I removed the fire ring by breaking it off. I then tried again to remove the plug, but the entire assembly continued to rotate.

So I removed more of the lava rock to expose the gas line. There are a few couplings in line. I sprayed more liquid wrench on the threads, put one pipe wrench on the line and another pipe wrench on top, and tried to rotate the top wrench while keeping the gas line stationary. No joy.

Then I tried digging down to see how far the gas line would go into the earth before it reaches the elbow. So far I haven't reached that point. If I can expose the elbow so that I can be sure that dirt won't fall into the interior when I remove the pipe, that would be an alternative.

After this experience it is clear that I have no interest in becoming an archaeologist... Don't know how convicts in the old days were able to dig themselves out of prison...

A few questions for the group:

1. How deep underground will the gas line run?
2. How to gracefully separate highly rusted iron pipe couplings without destroying the pipe?
3. Where is the likely point for the flow of gas to be interrupted which necessitated my messing around with the fire pit to begin with?

 

Thanks for all of the helpful comments!

I continued to dig and was able to expose the elbow at the bottom of the vertical run. It was ~15" deep. I unscrewed the old pipe so that I could see into the elbow. Looked like a cobweb in the opening. I stuck a screwdriver in the opening to see what I could scoop up. Not much came out. I opened the gas valve to see what would happen. No gas came out.

I closed the valve, and got a vacuum cleaner. Since I smelled no gas I used the vacuum cleaner to apply suction at the elbow. Not much came out. I turned off the vacuum cleaner and opened the valve again. No gas.

So I went to Lowe's and bought the appropriate lengths of new iron pipe and fittings to make up a new vertical run up from the elbow, plus a cap to seal off the opening. I installed the new pipe and filled back up the hole surrounding the pipe. When I receive the new gas ring I will install it, then call for professional help since this has gone beyond my comfort level.

Starting from the gas meter, the first outdoor appliance is the swimming pool heater. That has a shutoff valve in plain view. The next appliance is the BBQ grill and that also has a shutoff valve within the island. The last appliance in the line is the fire pit but it has no shutoff valve that I am aware of, besides the valve under the stone tile floor that I open/close with a normal removable key, just like you would use for your fireplace gas log. I looked all around for such a shutoff valve and could not find one. I confirmed this afternoon that the BBQ lights up fine.

The fire pit is around 14 years old and was installed by the original owners. We have lived in this house for 9 years.

Unfortunately since all of the gas line to the BBQ island and the firepit is under the stone tile, it looks like the tile will have to be broken up to access the valve and the line. What a PITA...

 

An update for those who might be interested:

$1,000 later, the fire pit has been restored to full operation. A plumber came out for 1/2 day, dug out the contents of the fire pit, used a jackhammer to remove some concrete in the way, and found another pipe that had rusted through. After replacing the pipe there was still no gas at the end of the line.

It turns out that water had accumulated in the line. He first tried using the pressure from the gas system supplemented by a shop vac sucking at the pipe. Amazingly, the vac didn't blow up. Although quite a bit of water came out of the line, some gurgling remained present.

Then he turned off the gas supply valve and hooked up an air compressor to the point where the BBQ connects to the line. He hooked up a valve at the fire pit to release pressure. Then he closed the valve at the fire pit and pressurized the line to 60 psi. When he opened up the fire pit valve, more water shot out. This turned out to be a highly effective means to clear water from the line.

After the line was cleared, he refilled the contents of the fire pit and then installed the new 24" fire ring that I had previously purchased. He also replaced the valve stem which controls flow of gas to the fire pit. He did not have to break up any tiles, so that was very good news. The fire pit works great now and we will probably roast marshmallows tonight to celebrate.

 

Hi Hal,

That's just one of several activities.

Yesterday and today I've been dismantling an old Baldwin electric organ that no longer functioned. This dates back to the mid-80's and has ~50 circuit boards. Amazingly complex. I would say this was the most complex consumer electronics device ever sold. My mom bought it new and my dad shipped it to us after my mom passed in the late 90's.

The organ failed back in 2007 and I was actually able to repair it after buying the service manual. It turned out that a digital latch IC had failed and I was able to buy a replacement from an electronics supply house in Texas. A few keys were not working but I managed to restore them to operation.

Most recently the organ appears to have multiple failures and the diagnostics no longer can be invoked so I had no idea where to start. There are at least seven microprocessors that control the organ and my guess is that one of the microprocessors was putting bad data on the communications bus. The microprocessors are custom.

I think a bad wiring harness was part of the problem (Salvage Prius prospective buyers take note...) Its amazing that this device lasted 25 years considering the connections are tin-plated, not gold-plated.

The organ weighs ~500 lb and I wanted to dispose of it in a responsible manner as well as minimizing cost. So I started by removing all of the electronics content. I'm saving the power supply, voltage regulator board and three audio amps (50W each) for future use. I took all of the digital circuitry and control panels to the local dump where a household hazardous waste center accepts this stuff (containing lead and thousands of electronics components) for recycling.

I removed all bolts/nuts holding the cabinet together and used my circular saw to cut up the wood so that it would fit into the "green waste" bin. I put all of the scrap aluminum and steel into the "recycling" bin.

Once sufficient water cleared out of the line, the gas was flowing freely. It ran for a total of 30 seconds while the plumber was using the vacuum and the smell of natural gas was everywhere. Even so, some water remained in the line so that was when the plumber decided to turn off the gas and use compressed air to blow out the remaining water in the line.