I'm doing some remodeling and moved a gas range over a bit. I made all of my connections using Rector Seal #5 and tested the joints using soapy water after turning the gas back on. Then I decided to pressure test all of the gas lines in the house. I shut off the gas outside by turning the shut off valve to the horizontal position. I disconnected the gas furnace and water heated and shut off the valves at the appliance. Finally, I put a 15 lb gauge on the line and used my compressor to bring the air pressure up to 15 lbs. The pressure started declining right away. I soapy water re-checked my connections and found no leaks. Then I went outside and found that the emergency shut off valve was leaking. I tightened the nut on the valve and the leak seemed to go away. But after re-pressurizing the lines the leak was slower but still there. I crawled through the fiberglass insulated attic spaces and checked every connection with the soapy water...no leaks were found. Note - this is a guest house...the gas meter is at the main house ...from the meter the line Tee's into the main house and to the guest house...they both have their own emergency shut off valve. When I went up to the main house to wash off the fiberglass my wife told me that the gas range had quit working. She said that it had come on fine for a short time and then quit. I went back to the guest house and let all of the air pressure out of the lines and left the emergency gas shut off valve in the off position. I went back to the main house and was able to get the gas range to work after trying for a few minutes. I also had to relight the water heater. It seems to me that the air pressure from the guest house pushed all of the gas out of the lines all the way up to the main house (about 75 feet away) even though the emergency shut off valve was turned off at the guest house. My plan for tomorrow is to shut off the gas at the gas meter...remove the emergency shut off valve from the guest house...cap off the line outside the guest house and re-pressurize the guest house lines to 15 psi. If that holds I'll replace the emergency shut off valve and retest. Any other ideas on what might be going on here? Thanks