Replies

1. 
   hybridoak | Dec 19, 2003 05:06am | #1

   You should hire a gas technician.

   but I installed my own heaters and Im not a plumbing/heating guy either.  I do know that you can use gas fittings for different sized copper lines.  These fittings require a flared end on the copper line to create the necessary seal.  to test for leaks, good soapy water.  You can find fittings for iron, copper, and even flaring tools at plumbing supply and even local hardware stores.  Be Very careful, and have it tested by the gas company before reconnecting adn running gas to the systems. 

2. 
   OneofmanyBobs | Dec 19, 2003 03:14pm | #2

   All copper-copper joints need to be silver soldered, not sweated with plumbing solder.  Either that or use compression fittings.  I think you're not allowed to use the compression fittings indoors except maybe for the one valve at the appliance.  Also rules about not stacking couplings.  Threaded black iron seems to be prefered indoors.  The pipe is sized according to the appliance BTU and length of run.  The pipe is not the same size as plumbing copper.  Goes by inside diameter, not outside.  Pressure testing is an absolute must.  Around here, they will not even sell you the fittings and pipe unless you're a licensed gasfitter.  You need a primary regulator at the tank and a secondary where the line enters the building.  Both must be outdoors.   There are enough tricks to this that I'd get a plumber/gasfitter to do it. 

3. 
   Jeff | Dec 19, 2003 05:15pm | #3

   Bird

   First, let me say that I'm not a plumber or gas person.

   Here in Vermont, residential stuff doesn't require a license to do things and all the fittings are available at the larger hardware stores.

   I have alot of gas appliances at my place (stove, furnace, generator, and shop heaters) all that I've installed myself.

   Interior piping is usually black iron, to prevent damage to it, but if exposed and open to inspection, copper is ok.

   But, that said, alot of people use the soft copper gas piping to do the hook-ups.

   Everyone uses the compression fittings, no one solders them (at least around here.)

   The place where you get into trouble is when tha gas company installs a tank.

   If the gas company doesn't install the pipe, some won't even hook up unless their removing another companies tank at the same time.

   Their insurance forces this policy.

   I do all the piping and installation myself, and let the gas company make the actual hook-up to the tank (with regulator) and appliance.  They make the actual fitting together of the pipes and test it.

   This saves time for them (and cost) and covers their insurance liability,

   They also will not use a customer supplied regulator here if it's not tested before installation.

   I find it easier to do it this way and the last hook-up cost me $35.00.  I'd already done all the hard and skut work for them.

   Hope that helps some, and check with your gas supplier on their policy.

   Jeff

4. 
   johnnyd | Dec 19, 2003 05:46pm | #4

   I'm also not a certified gas technician, but follow the safety rules gleaned from this board, a plumber BIL, and my LP gas supplier.

   I use either 1/2" or 3/8" soft copper....type L I think, thicker walled than the "M" that can be used for water....and flare fittings.  You need a flare tool and need to know how to use it.  There are tables you can find on the internet that give you the size tubing required per length of run and BTU rating of appliance. 

   Good rule of thumb is to never have flare fittings/couplings, or unions permanently concealed or even within a crawl space...run a constant, unbroken line of tubing from the outside regulator to the shut-off valve before the appliance.  You've always got to have a separate shut-off within sight and usually in line right before the appliance. A verticle drip leg should also be in line before the appliance.

   Alot of this is common sense and can easily and cheaply be over-built, like if there's a doubt use 1/2" 'stead of 3/8".

   Check all connections with soapy water and a little paint brush.  Even the slightest leak will blow big bubbles.

   Why not visit a friend or nieghbor that has had a professional install and copy the routine for yours?

1. 
   ndege | Dec 19, 2003 05:56pm | #5

   Thanks for the advice. I'm not installing this new but actually moving it across the room. So I'm looking to simply add to the existing installer's work. It's set-up with 3/8 flex now, black pipe going into the unit. I had wanted to run rigid copper (exposed) because it's cheaper. I have to run the line about 50-60 feet from tank to unit. Where can I find these table to figure out if 3/8 can do the job?

1. 
   johnnyd | Dec 19, 2003 06:16pm | #6

   Let me see if I have this straight:

   It's LP...Propane...right?  Are you saying that there is now 3/8" flex through the wall from the regulator to the black pipe fitting, and then a drip leg and a shut-off valve? Or is the tank inside?

   Does the black pipe go all the way into the heater?  How big is this heater? 

   I think one of the reasons you never see rigid copper in gas line is because niether compression or flare fittings work very well, or at wall, with rigid copper.  Think about it...if you used rigid copper with sweated fittings, and then had a pin hole leak that you found out about after the line was pressurized with gas, how would you fix it? I wouldn't want to get the torch out then.

   Anyway, running 50 - 60 feet for a heater gets you close or over the line between 3/8" OD and 1/2" OD soft copper.  Why not just get the 1/2"? Not that much difference in price.

   Take a look here:  http://www.firelogs.com/gasline.htm

   Edited 12/19/2003 10:18:15 AM ET by johnnyd

5. 
   davidmeiland | Dec 19, 2003 06:40pm | #7

   Pressure testing should be done with an air compressor and a gauge/pressure fitting that lets you 'inflate' the lines with an air chuck. Once you've built the pipe, connect the gauge and pump the lines up to 20 or 30 PSI. There should be no drop at all, even over days, ASIDE from an initial drop of 1 or 2 pounds within a few seconds after you inflate. If there's an inspector involved they will require that the lines hold a test for a certain period, while they are on the site.

   If you use gas shutoffs with a test port, your LP company will be able to test the lines and the appliance gas valves after the whole thing is connected to gas and ready to go. The correct valves have a small removable plug on the side that lets them connect a water-column device. This tests for low volume leaks.

   I think copper gas line is illegal in a lot of places. The concern is that a plumber will confuse it with a water line and cut into it during a remodel. I use black iron for mine. I've got a threader, a vise, and two wrenches--that's all it takes. Iron pipe is pretty much indestructible.

6. 
   DSorg | Dec 19, 2003 11:20pm | #8

   You might also consider using Gastite or similar (http://www.gastite.com ). I just used it in a remodel. It's a single length of flexible tubing, just one fitting on each end. Quick, easy, code compliant most places. The tubing costs a little more than iron, but way faster with only two (unlikely) places for a leak.

1. 
   johnnyd | Dec 20, 2003 12:34am | #9

   I've heard about this, but doesn't it require some training and special tools for the fittings?  May rule it out for DIY with a flaring tool.

1. 
   steve | Dec 20, 2003 02:03am | #10

   never ever use compression fittings or solder fittings for gas service

   both are against the gas codes almost everywhere and will invalidate your house insurance

   gas either propane or natural must be taken seriously, and if you have to ask the question, dont do it!!! hire a pro

   i've seen what happens to a house after a gas explosion and it aint prettycaulking is not a piece of trim

1. 
   Jeff | Dec 20, 2003 04:49am | #11

   Steve

   YOU ARE CORRECT!!

   I reread my post and realized I wrote compression fittings, when I ment flair fittings.

   Jeff

1. 
   ndege | Dec 20, 2003 08:03am | #12

   I've had a real education here. Called the gas guys to do the hookup though I may still run the line. Can that copper line be covered up? Or is there another recommendation for inside walls?

2. 
   steve | Dec 20, 2003 03:21pm | #13

   in ontario cananda, copper gas line MUST not be covered in any way and must also be tagged as a gas line i believe every 3 feet

   imagine what would happen if even a picture hanging nail was driven into it.

   a few years ago, a house literally exploded when a gasleak filled the house with gas and the furnace kicked on. i was living about 6 blocks away and im sure my house moved.

   the exploded house was nothing but a pile of burnt rubblecaulking is not a piece of trim

3. 
   Jeff | Dec 20, 2003 03:43pm | #14

   Bird

   Different locations have different rules.

   Here in Vermont, only a hard pipe (Black Iron) can be covered up in a wall or ceiling.

   Only problem is the joints, how do you test one that's covered.

   I know my stove pipe (copper) is hidden in my basement ceiling, but has no joints to leak.

   When I changed gas companies, they advised me to replace it with Black pipe, but since it was already in the ceiling for 10 years, they allowed it.

   Jeff

4. 
   jako17 | Dec 20, 2003 06:07pm | #15

   One other point about pressure testing is that most gas valves and certainly regulators are made to stand only inches  of water coloumn pressures so for line testing I isolate  the pipe and give it 25- 30 psi then connect the valves etc.  Once those are connected I do a lock up test using the gas supply and a manometer.The manometer gives readings of 0.1 inch w.c (1 psi is 28 inches of w.c)So even the temp of the gas warming up in the house gives a slight rise in pressure

5. 
   DaveRicheson | Dec 21, 2003 07:57am | #16

   Our natural gas service techs routinely pressure test gas line at 1 psi for 30 minutes before turning on a customers service. They use compressed air. Gas appliances normally have a working pressur of 6 to 8 oz. If the customers or plumber/gas fitter repair or new install passed thier pressure test, the tech purges the line and lights all pilots, and  uses a sniffer to further check for any leaks.  Any leak at all will keep the gas cut off, no matter what! I would assume that LP providers would be covered by the same federal and state regulations that natural gas companies must comply with.

   BTW all, piping diameter is measured by inside diameter (I.D.), tubing is measured by outside diameter (O.D.)

   Dave

6. 
   BillHartmann | Dec 21, 2003 07:52pm | #17

   "Gas appliances normally have a working pressur of 6 to 8 oz"

   Isn't that 6-8 inches of water?

   And if I read my conversion table correctly 6" of water is 3.47 oz/sq in.

7. 
   jako17 | Dec 22, 2003 01:47am | #18

   I think you will find that most gas appliances have a working pressure of about 3.5 inches of water (w.c.) .As I posted  1 psi = 28 " of w.c     i.e 3.5 wc = 2oz /si.We were required to test at 25 lbs for 30 min for working press up to 3.5 "wc and 50 lbs for working press of 3.5 to 230" w.c.IMO 1psi is not great but may have been adopted because it probably saved taking valves and other equipment out of service because of damage from the pressure