Running gas line for new oven

[jpbusch]

Hello,
We purchased a new gas oven to replace our old eletric one. The model number is GE cafe CGS985SETSS. I have easy access to our gas line which only feeds our water heater and furnace right now. I am able to T off the main line where it goes from 1" to 1/2" for the water heater. So, I can run what ever size is needed. The manual states either 1/2 or 3/4 line. I have to run about 30ft of pipe before going up to the kitchen. So, my question is what size is the right size? 1/2 or 3/4? A link to the manual is here http://products.geappliances.com/Ma.../Dispatcher?RequestType=PDF&Name=49-85183.pdf
It basically says 5" to 13" water column. Any help would be great.

Thanks

 

[Mr_David]

3/4" would probably be the better choice.

The size of the pipe is calculated by the total demand on the system and the total developed length from the meter to each appliance

To properly size the minimum required pipe size required, one needs to now the total developed length from meter to each appliance and the BTU rating from each appliance.
Here is an example of a sizing diagram.
If you could make a simple sketch with aproximate pipe distance to each appliance and the BTU rating of each appliance similar to the attach drawing I can give you a more accurate answer

 

[havasu]

Mr David is correct. Stay with 3/4" minimum, because anything less will reduce volume too much.

 

[LiQuId]

This is a TERRIBLLE IDEA.... unless of course you are a qualified gassfitter.

pay to have this done by somebody who is licenced in the trade, this is NOT a job for a homeowner to attempt, and if you need to ask sizing questions then you are NOT the person who should be doing this. potentially this can be very dangerous and your home insurance wont cover anything. When you hire a professional We have liability insurance to carry out this kind of work and also ( and often more importantlly ) experience.

IF you decide to attempt this then you should know how to make and use a manometer, and be aware that the maximum pressure drop for Ch4 is 1" w.c. ( again if this terminology is lost on you then DONT do this job )

 

[jpbusch]

This is a TERRIBLLE IDEA.... unless of course you are a qualified gassfitter.

pay to have this done by somebody who is licenced in the trade, this is NOT a job for a homeowner to attempt, and if you need to ask sizing questions then you are NOT the person who should be doing this. potentially this can be very dangerous and your home insurance wont cover anything. When you hire a professional We have liability insurance to carry out this kind of work and also ( and often more importantlly ) experience.

IF you decide to attempt this then you should know how to make and use a manometer, and be aware that the maximum pressure drop for Ch4 is 1" w.c. ( again if this terminology is lost on you then DONT do this job )

So let me get this straight. While I have installed 2 furnaces both with AC, installed 2 below grade bathrooms including all of the associated plumbing and venting, 2 water heaters, re-wired my entire house including adding a sub-panel to the garage, hard pipping my air compressor around the entire garage (with no leaks). I should pay a plumber to go to home depot to buy 3/4 black threaded pipe for a bit less than I would be able to buy for, then mark it up to resell to me. Dope up the ends t into the main gas line, after turning it off at the meter. Run all of the pipe, and couplers, turn the gas on, check for leaks using soapy water, tighten it up if it leaks. For between $500 and $800. While I can purchase the materials for under $150.00
While I appreciate your concern and not knowing my ability for home improvement, the 2 main issues as I see it are making sure that the appliance is getting adequate gas flow and that there are no leaks in the line. If my only option according to the appliance manufacturer are 1/2 or 3/4 pipe. It seems like 3/4 is the correct option, then making sure there are no leaks which can be accomplished with the correct amount of pipe sealant and tension. The fail safe is the test with the spray bottle and if it leaks tighten it up again.

 

[DFBonnett]

OP,
When I did it I used 1/2" and have had no problems with capacity.
FWIW
YMMV

 

[LiQuId]

double post error ..

 

[LiQuId]

the line should be properly sized at least, if you exceed the maximum pressure drop bad things can happen, mostly annoting things like pilots extinguishing themselves but potentially worse COULD happen. Forgive me for lending some heed to caution as You had asked a question which i assume you intended to be answered by professionals ( as I am a ticketed A class gas fitter ) , Since you are pro then you likely also know that Any branch you take off of a gas main must be done within the first 2 feet of the regulator, there are a few other code clauses to observe like not using close nipples or nested bushings, and not taping the starter threads or using excessive dope as it WILL plug your orifices which im sure you already knew. heres another peice of advice, Dont be a dick to people who are concerned for your safety, I know nothing of your abilitys ( only what you SAY ) and your reaction is strangely defensive and does not serve you in your persuit for answers.

Careful with ch4 and be even more careful if you run on c3h8

 

[LiQuId]

Forgive me for Re-asking.

You do know how to use a manometer also then ( since you specified the W.c. inches in your original post )