Since two weeks ago we began to notice a low-tone "gas-flame like" sound near center of the house. It comes on for about 5 seconds and off for about 23 seconds, continuously 24/7. The sound is gone when the water is shut off from the water-meter. All of the faucets, bathroom water tanks, and outdoor spigots are checked and found to have no leak. Please help us solve this mystery. Thanks.

Since the sound goes away when the supply is off, you obviously have a leak. My guess is a leaky toilet flapper causing the ballcock to cycle-phantom flush. That's the only thing that cycles. Put some food coloring in the toilet tank and see if the water in the bowl changes color. If it does, the flapper is bad, warped etc, very common. Easy replace but check the seat to make sure its not cracked or pitted. Repair kits for that are available at little cost. Hope this solves your problem. Let us know.

Since the sound goes away when the supply is off, you obviously have a leak. My guess is a leaky toilet flapper causing the ballcock to cycle-phantom flush. Thats the only thing that cycles. Put some food coloring in the toilet tank and see if the water in the bowl changes color. If it does, the flapper is bad, warped etc, very common. Easy replace but check the seat to make sure its not cracked or pitted. Repair kits for that are available at little cost. Hope this solves your problem. Let us know.

Dear ma0641: Thanks for taking time to help me solving my problem. Unfortunately, it does not work. I did what you suggested with food colors. I even shut off all water valves leading to the toilet water tanks. The cyclic sound continues. What now? I need more help. Please. Thanks.

It still has to be something related to the water system if it goes away when you turn off the water. You can usually turn off the house water at 2 places, at the valve box and inside the house. Turn off the valve inside the house and leave the street valve open. Anything change? Leave the water on and go to the hot water heater. On the top or side of the heater is a T&P safety valve, connected to a pipe. Sometimes they go bad and will cycle as they relieve pressure although not usually systemic like this. See if you can hear it there. Turn off the cold water valve into the hot water heater. Any change? Where do you live? Have a swamp cooler? There is s fill valve on them. I would start shutting off everything that has a water supply-boiler, ice maker, sprinkler control valve, There aren't many more things left. We'll figure it out.

Do you have a water softener, or R.O. system? ma0641 gave good advice, please let us know what you find.

Do you have a basement? And if you do is it possible that you have a pump in the basement. Something like a condensate pump that is discharging water but the line is partially stopped up and it is not emptying the tank the way it should.

Might be but they stated the sound goes away when the water to the house is turned off. Condensate pumps don't use water.