Kitchen Gas Appliances - Gas Piping - Flexible Copper vs Black Iron

I have recently moved into an older house and in the process of having a new gas dryer hooked by the appliance store people, they noticed that the old dryer had flexible copper piping and wouldn't touch the job. They left, leaving the old dryer connected and the new dryer sitting on the floor in its box. I have natural gas. They said if I had propane gas the flex copper was O.K., but not for natural gas.

What's the problem?? Gas is gas, isn't it??? Why should it matter if natural gas or propane gas is going thru a flexible copper pipe?? Flexible copper is much easier to work with.

Hello donnyboy and Welcome to the Do It Yourself Web Site and my Gas Appliance forum.

In all natural gas supplies there is a certain amount of sulfur. When copper comes into contact with sulfur, over time the sulfur will corrode the copper from within. As the corrosion pits the copper tube from inside, gas leaks will develope.

Copper is illegal to use inside any home or enclosed building structure in every part of the USA that I am aware of, for the reason stated above.

It was a correct decision NOT to install any gas appliance used in any enclosure to a copper gasline do to liability concerns on the part of the installers.

The entire copper line must be removed and replaced with iron or steel piping to meet housing codes. Gas pipe plumbers do this type of work. I sugest you contact one in your area.

Regards & Good Luck
Forum Moderator
Tom_Bartco
Energy Conservation Consultant & Natural Gas Appliance Diagnostics Technician.

Thanks, Tom, for your quick reply. You made it clear that I have some extra work to do.

I have the exact same situation as donnyboy, but the installers told me that a shutoff valve needs to exist 3 feet above the ground. I also have flexible copper piping. Is this some sort of regulation that a shutoff needs to be 3 ft above? Along with replacing the copper piping, do I need this shutoff valve that the installer is talking about? Or is replacing the copper piping alone enough?

Hello MichiganMan and I Welcome you also to the Do It Yourself Web Site and my Gas Appliance forum.

Codes vary from state to state and county to county, etc. I suggest you inquire about this 3 foot high shutof valve with your local building and safety department.

I personally do not see any reason to install the valve that high above the floor level. But there may be good reason.

I suggest you also inquire about the copper pipe. There are copper pipes that have tin lining and are exceptable for use with natural gas. However, it's an expensive copper pipe and only used in mobile homes to my knowledge.

If your home isn't mobile, the copper should be removed and iron or steel piping installed. A shutoff valve installed on the pipe should be about 3 inches or so above the floor, if the gas pipe is under the house and entering the room through the flooring.

Regards & Good Luck
Forum Moderator
Tom_Bartco