I'm upgrading my kitchen and bought a 6 burner Wolf range. The instructions state that I need 3/4" pipe to the wall, but can use 1/2" hose for the last 3' connector. Of course I wasn't told this when I bought it, and it turns out I have 1/2" pipe. I went into my crawl space and see that I have a 1" pipe that has a "T" which then becomes 1/2" pipe for about 12' to the range. So my questions is this, if the last 3 feet are 1/2" flex hose to the range, why can't the pipe be 1/2" too? The 1/2" pipe is a dedicated line to just the range. The Wolf representative says their specs required 3/4" pipe because that is the only way they have tested it. And a plumber that came by also recommended I upgrade, but of course that gives him extra work. He quoted me $1700 in time and material to remove exiting pipe and replace with new one, which does require opening up a drywall to access it, but that seemed very high. To me it seems like the 1/2" hose is a choke point anyways, so what difference does it make if the pipe leading up it is also 1/2" rather than 3/4". I need to make a quick decision since after the kitchen remodel it would be an even bigger cost to replace it all.



Edited 1 times.

We can answer your question when you tell us the total BTU capacity of the range. And we are assuming that you are on natural gas.

The pipes are sized according to pressure drop.It starts at the meter, which must be rated for the combined load of all the appliances in the house. Depending on what you have, and where it is, all the gas pipes in the house may need to be replaced. Plumbers use charts and formulas to properly size gas lines. If not sized correctly, nothing will work properly.

We can not give an accurate answer. We would need to do a load calculation on all gas appliances , the total btu, lengths of piping, whether you are on a 2 PSI system, natural or propane, etc.

if Wolf makes a range rated 1/2" pipe, GET IT

listen to ALL ABOVE POSTS

this advice is PERFECT and CRITICAL to your health and safety

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

The Wolf Range is 6 burner, 5x15000btu and 1x9000btu rangetop, 30000btu oven and 18000btu broiler.

I'm in San Diego CA using Natural gas.

I have a 34000btu water heater, I'm not sure about my heater for the house but I never use it, and I have a gas fireplace.

I am still curious to hear the theory behind why I would need 3/4" pipe when it gets reduced to 1/2" flex hose. Isn't the 1/2" flex house the choke point? I understand that 3/4" has more volume, but it gets reduced down to 1/2" at the end. What difference does it make if that happens at the flex hose vs having 12' of 1/2" pipe leading up to it. The current 1/2" pipe is dedicated to the range only and comes of the main 1" pipe from a T.

it all has to do with 'friction loss per foot of pipe' tempered by the actual gas supply pressure

listen to Wolf, or warrantee is void

spend for what you want, or change what you want to meet budget, or modify what you want

do it right the FIRST time

ps. the 1/2" supply 'tube' is sliiiightly larger ID and smoother than the 1/2" pipe

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

I am still curious to hear the theory behind why I would need 3/4" pipe when it gets reduced to 1/2" flex hose.


Spend 15 minutes watching this excellent training video.
[www.youtube.com]

Or, you can get a little more in-depth by setting up your own Boyle's law demonstration:
[www.boundless.com]

Or, just leave the pipe at 1/2" and see if it works well enough to keep you happy. No one here can make you change it, although your local authority might have something to say about it if you're planning to get a permit and have it inspected.

It's easy for me to say I'd change it, because I'm not doing the work or spending the money. But if you bought this for the name and shine, and all you ever do is boil water and heat pizza, it may work fine. If it doesn't, though, you'll know where to start.

*******************************
Links to the State of Wisconsin Plumbing Code:
[docs.legis.wisconsin.gov]
*******************************
I am not a plumber.
*******************************

Quote

Or, just leave the pipe at 1/2" and see if it works well enough to keep you happy. No one here can make you change it, although your local authority might have something to say about it if you're planning to get a permit and have it inspected.

You MUST get a permit and get it inspected. The law is NOT optional.

While a 'cheat' may work for YOU, how about the next (unsuspecting) owner?


DO IT RIGHT THE FIRST TIME

Either:

Change the range to match the existing gas piping

or

Change the gas piping to match the new range


ps. failure on your part to know what you were purchasing does NOT matter

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

quote; the 1/2" supply 'tube' is sliiiightly larger ID and smoother than the 1/2" pipe

YOu must NOT use the corrugated flexible gas connectors, Which ARE smaller due to the corrugations, and LESS smooth for the same reason.

Gas being a vapor, is funny. You can have all the charts and rules, but until you actually try it, you will not know if it will work or not. I once encountered a gas system that the charts and rules said could NOT POSSIBLY work, but had for over 20 years. When I asked the gas company when they had reduced the pressure from a 2 psi system, which is what it was piped for, and had the proper regulators for the higher pressure, they said it had ALWAYS been a 6 inch system and had no idea how it worked that long. Incidently, it had 1,300,000 btu on a 330' one inch line.



Edited 1 times.

according to this chart you are OK..
[www.aprsupply.com]

That chart applies to the length of the ENTIRE system, from the meter to the furthest appliance including fittings. You CANNOT use it for a single branch line. If you could, installers would be computing every system as bunch of short lines between branches, and seriously undersizing everything.

hj,

D'OH brain freeze on my part D'UH

guess i'm getting senile



go ahead, say it


? getting ?




==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

So I took the advice to try it and see if it works before replacing it. I hooked it up using 1/2" supply line (http://www.homedepot.com/p/BrassCraft-Safety-PLUS-1-2-in-MIP-Excess-Flow-Valve-x-1-2-in-MIP-x-48-in-Stainless-Steel-Gas-Connector-1-2-in-O-D-60-500-BTU-CSSD44E-48-X/100634421). Is there a better supply line that I should be using than this?

I haven't seen a Wolf range in action so it's hard to tell if it was working exactly as expected. I'm guessing that even with 1/2" pipe at least one burner should work at full BTU, right? When I turned on the first burner it appeared to put out some serious heat. I was able to turn on all 6 burners without any decrease in output. I was then able to turn on the oven without any decrease either. I then decided to turn on my gas fireplace, dryer, water heater, and furnace, and I still didn't see any decrease in the range top output.

So to me it seems like I should be OK with what I have. Is there any reason I shouldn't save the $1700 I was quoted to upgrade to 3/4" and just stay with what I have? Is it against code or are there any safety concerns with using too small a pipe? I know it doesn't seem to follow all the theory of pipe size vs length, but it appears to be working unless there is something I'm overlooking.

thanks for all the good education and advice



Edited 2 times.

Read all of HJ's post above. I've also come across similar strange gas piping that should not have worked, but did.
It's your place to gamble with.

For >100K BTUs I either hard-pipe or use a commercial flex connector, like this one (scroll down the page a bit to the expensive flexes):

[www.plumbingsupply.com]

around here.. new england... the concern for starving gas to appliances comes in the dead of winter when there is soooo much demand all at once. on a night when the temperature is below zero, everyone who heats with gas is consuming fuel all at the same time.
accordingly, gas mains were made larger and pressures were increased to keep up with the demand.
you should not have that problem in CA. so, if your stove worked with your house on maximum demand, i would not worry.

jakeb,

? what will the building code inspector say ?

THAT is your REAL concern

If the work required a permit and none was obtained THEORETICALLY the work and any damage caused by it will NOT be covered by your insurance policy.

?Don't believe me?

Ask any agent (anonymously) !

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

If you are really concerned about it, call a plumber who knows how to "clock" the meter while everything on the stove is turned on and see the btus being used. That will tell you whether the supply is adequate or not. The only thing turning all the appliances on at once will tell is whether the meter is large enough or not.

You DO NOT need a permit to connect a gas range, and if one were required it would be something that EVERYONE ignored.

Quote

If the work required a permit and none was obtained THEORETICALLY the work and any damage caused by it will NOT be covered by your insurance policy.

? Did you miss the word "If" ?

Really do not know what "upgrade a kitchen" includes.
If merely a range swap the OP is 'good to go'.

You DO need a permit to renovate a kitchen.

as per the OP:

Quote

I need to make a quick decision since after the kitchen remodel it would be an even bigger cost to replace it all.

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 3 times.

a gas permit to hook up a range may not be required in the known universe but it certainly is required to be done by a licensed gasfitterand inspected by the local authority here in massachusetts.

jakeb,

I'm glad your 'test' worked OK for you.

however

as per your link:

3/8 in. I.D. (1/2 in. O.D.) corrugated stainless steel with corrosion resistant coating
•Safety+PLUS excess flow valve protects against gas fires and explosions - 1/2 in. MIP connection to gas supply or gas ball valve
•Safety+PLUS valve ideal for most common household gas appliances
•Safety+PLUS valve features automatic activation and reset
•Safety+PLUS valve is 100% factory performance tested
•Safety+PLUS valve installs like a standard gas fitting; can be installed in vertical or horizontal position
•ProCoat coating corrosion resistant to harsh chemicals as well as UV rays and salt
•Use with natural and LP (propane) gases
•Gas connector is 100% leak tested
•Approved for indoor and outdoor use
•Temperature rating: 32° F to 150° F
•Pressure rating: 1/2 psi maximum
•Designed, machined and assembled in the USA
•CSA certified

You are GREATLY choked at the final supply connector.

"Most" connectors (after researching) are 5/8 OD with nominal 1/2 ID

I hope that you tested during a peak period of 'neighborhood use' of gas which could lower available supply pressure.


In any event,

BEST OF LUCK TO YOU

(make sure you 'bubble test' the connection after 90 days for safety)

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

Since it appeared to work fine with all my gas appliances on full I think I will keep it as is. In just the few minutes I had the range on I managed to heat up my whole upstairs several degrees, so I don't think my furnace and fireplace would ever be on while the stove was in full use. Seems like I can save myself $1700 and keep what I have right now. Thanks for all the feedback.

I had someone on another forum tell me the following

"my understanding is, if starved for gas, the oxygen fuel mixture at the burner is not correct, causing a build up of carbon monoxide, you cant see it, you cant smell it you just drift off to sleep"

If the range appears to be working properly with 1/2" pipe is this a legitimate concern? If not, are there any other concerns?

You do NOT have 1/2 pipe to the range unless you 'hard pipe' it.

You 'should' have 5/8 OD connection - 1/2" ID

You ACTUALLY have 1/2 OD connection - 3/8" ID

Your CO concerns are valid - especially with a six burner 'commercial' range


Have an actual plumber / gas fitter connect your EXPENSIVE shiny new COMMERCIAL grade range.

You wanted it - you bought it - now you get to pay for it

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Go to heatinghelp.com , and put a shout out for Tim McElwain on the "Wall". He runs a gas training institute in Rhode Island. He won't discuss pricing with you, but whatever he tells you, take it as gospel. Oh.....I believe he is also a Minister.



Edited 1 times.

CO is caused by INSUFFICIENT combustion, meaning TOO MUCH gas for the available air, which would NOT be your problem.

In other words if his advice kills you he can take care of the services also.

hj,

EXCELLENT point WELL TAKEN

D'OH

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Gas Supply
Installation must conform with local codes or, in the absence of local codes, with the National Fuel Gas Code.
Locate the gas supply within the shaded area shown in the illustration on the following page.
The range is equipped for use with natural or liquid propane (LP) gas. It is design certified by the Canadian Standards Association (CSA) for natural or LP gases. The product rating plate has information on the type of gas that should be used. For rating plate location, refer to the illustration below. If this information does not agree with the type of gas available, check with the local gas supplier. The gas pressure regulator is built into the unit.
GAS REQUIREMENTS NATURAL GAS WC Supply Pressure 5" (12.5 mb) Min Line Pressure 7" (17.5 mb) Max Regulator Pressure 14" (34.9 mb), .5 psi (3.5 kPa)
LP GAS WC Supply Pressure 10" (25 mb) Min Line Pressure 11" (27.4 mb) Max Regulator Pressure 14" (34.9 mb), .5 psi (3.5 kPa)
The range must be connected to a regulated gas supply. The supply line must be equipped with an approved external gas shut-off valve located near the range in an accessible location. Do not block access to the shut-off valve. Refer to the illustration below. A gas supply line of 3/4" (19) rigid pipe must be provided to the range. If local codes permit, a certified, 3' (.9 m) long, 1/2" (13) or 3/4" (19) ID flexible metal appliance connector is recommended to connect the units 1/2" NPT female inlet to the gas supply line. Pipe joint compounds, suitable for use with natural or LP gas should be used

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

California use to require ¾" minimum outlet for stove, but changed it to ½" minimum for any gas appliance. Of course if the appliance manufacturer states larger then ½", you must use the manufacturer's specification.

Whether you should or you should not... is not up to us. You have tried your idea and it seems to work for you. Once person you might consider asking is your home owner's insurance agent. "Would You Be Covered In The Event Of...... " You know what the factory specs are and the local codes but in the event of a "situation" would your insurance company use that for a reason for not paying a claim ?

Good Cooking and....
Best Wishes