Correct, WC is water column. With natural gas 1 PSI = 27 WC. Most residential houses (as I understand it) are about 20 PSI coming in stepped down to 2 PSI for the meter. It's still 2 PSI coming out of the meter which is then regulated down to 1/4 pound. That equals roughly 6.75 WC. The regulators are supposed to keep a constant pressure on the output side so 2PSI (aka 54 WC) is plenty. Since the pressure is mostly constant the only thing that can effect the flow is the size of the pipe. Technically you could achieve a similar BTU output by jacking up the pressure to about 1/3 of a pound (10WC or so) but plumbers are loathe to do that because it's non standard. With natural gas it's hard to argue with that logic. Curiously my old cooktop was the same way as cooks1818 just described. 1/2" pipe was all I could see but once we ripped up the floor, sure as shootin, it was all 3/4" that was stepped down for the last 18" or so. -Stooxie

You may not have to move the line at all. A foot away is nothing, and sometimes it is better than if it was right behind the range, because the end of the pipe might hit the range. Here's how it goes. If you can see the end of the pipe, there is probably a cap on it. There may also be a small red lever called a 'shut off valve'.. It's not the main shut off, just a small one for the range. If it's not there, you should add one. A plumber or someone can add this shut off valve in two minutes if it doesn't interfere with walls or cabinets. Otherwise they may have to extend the pipe either under the floor or in the wall. And yes, that is a bigger job Basically, the gas is shut off,(A clever plumber who has everything ready to go may not even bother to turn the gas off if the pipe doesn't have to be moved) ... the cap on the gas pipe in your kitchen is removed, and the shut off valve screwed on with teflon pipe putty. Now you don't need the cap, you just turn the valve to 'off' (this is always perpendicular to the gas pipe). And the gas can be turned back on -assuming it was turned off to install the appliance shut off valve. Now you're ready to go, simple install a gas flex hose from the small appliance shut off valve to the back of the gas range. These flex lines are usually about 2 feet long- but often longer. Once the flex line is installed,(usually running under the range, or between the legs of the range and then up the back to the connection on the range) you turn the small shut off valve 'on' and you're ready to cook. Now, the only tricky part is knowing where the gas connection is on the back of the range. Every manufacturer puts it in a different spot, but usually it's fairly low on the back. So, yes, you may have to add some gas pipe, or an elbow, because you don't want the gas pipe or the flex line to hit the range. Usually the gas pipe should be close to the floor and between the legs of the range,(either in the floor or low on the wall) or off to the side a bit if there is no interference with cabinets and doesn't show. The plumber will need to know this before doing any work, or you should have the range nearby for them to look at. Oh, and you're going to need an electric outlet nearby as well. This should also be close to the floor so the plug won't hit the back of the range, or again- slightly off to the side if there's not interference and doesn't look bad.

Removed old emergency shut off valve and capped the pipe off outside the house. Repressurized the lines inside the house and they held at 15 psi. Replaced the emergency shut off valve and placed it in the off position. Repressurized the guest house lines and everything is holding at 15 psi. I had to get the 1-1/4" valve at a plumbing supply house as Home Depot does not carry them. Moral of the story is these emergency shut off valves can leak internally. As to the question of why I pressurized to 15 psi to test the lines is because most building codes require it or somewhere around this pressure. If it holds at the higher pressure then most likely if will never leak at less than 1 psi. My problem is fixed...I hope this post helps someone else in the future.

Check your local code carefully before connecting this cooktop. Some codes do not permit flexible gas connectors but rather they require all gas appliances to be plumbed with iron pipe the full distance. For this reason the appliance manufacturers allow a rather large opening through the back of the appliance cabinet and the actual point of connection to the gas regulator in the appliance is in the front 1/3 to 1/2 of the appliance frame. This permits running a gas pipe from the wall and extending out about 12" to a gas cock type shutoff valve. With the large opening the range or cooktop can then be slide in place and the end of the gas line with the shut off will now be inside the appliance cabinet. Once in place the cooktop can be raised allowing access to connect a nipple from the stop cock to a union and a second nipple from the union to the 1/2 female iron pipe thread in the appliance gas regulator thus completing a rigid gas pipe connection. When using a flexible connect the codes prohibit a flexible connector from passing through any floor, wall partition, cieling or appliance housing. Ref: International Residential Code IRC-2422.1.2 Uniform Plumbing Code UPC-1212.0X2 Properly when connecting a gas range or cooktop with a flexible connector you must first install a rigid pipe extending from the gas regulator to the exterior of the appliance cabinet and the transition for rigid pipe to flex pipe must occur outside the appliance housing.