teflon tape on gas piping

[naturekid1]

I've been working in the hvac field for over three years. I'm the only boiler installer at our 8 person family run company. I run service, install and do good amount of sales and estimating.I used to be an auto mechanic for over 6 years. The other day, I realized I was out of pipe dope on a gas to gas job. nowhere near the shop, I grabbed my roll of Hercules teflon tape, usually reseved for boiler installs, to do the 3ft of gas piping requird. The package said 'usable on virtually all gas, chemical, alkaloid, water and corrosive liquid applications. Meets military standards up to 10,000 psi." I promptley used it, with no gas leaks, I felt it look a hella ot better than goopey yellow **** splattered everywhere. The county inspector promptly failed it. wanted goop. My boss claims TEFLON tape is not a lubricant and therefore won't propoerly seal threads, even though in the automotive field this is the standarized thread sealent, and in 6 years of swapping water pumps and radiators, I never had a problem. inspector not withstanding, is there any reason goop works better than tape, and or tape won't work?

[azair]

there is some kind of reaction that you get with the tape\teflon and the gas.
It is against code here. PHX. The yellow is designated for the gas, and if anyone can explain why ....

[cem-bsee]

I specified & use Loctite liquid sealing for all threaded joints.

a lubricant is to allow one to easier thread together parts -- it is may not be designed as a sealant.

in general, PROPERLY made threads make the seal, or hold the load [in bolted connections].
EACH time a threaded connection is remade, some strength is lost.

another benefit with Loctite, it prevents corrosion.

I have never seen a reaction with Teflon & gas --
BUT, the composition of gas VARIES with its source!

like, I have never seen a problem with copper & natural gas -- others report serious problem with this combination in their area!

[Airmechanical]

leak lock is my preferred thread sealant

some of the techs here dont like it

i have never had a problem with it

the only problem i ever had with it is when i ran out of it

i have used it on drain fittings for a 1-1/2 ton airhandler

i have used it for brass to steel access on 80 ton chillers

it is the greatest sealant ever made



,

[lbrombach]

I never use it for gas, but I'm pretty sure it is not against code here (MI). I like the green stuff, personally. I once bought this really pretty blue stuff that worked good. Hate the cheap crap.

[rjw_hvac_tech]

Teflon tape dries out and shrinks when used for natural gas. Over time will fail there is a non potrolium thread sealant tape (yellow) that is suppose to be ok - dont know if its ok by code. I will stick with pipe dope

[tinner73]

i always use both.

the tape is the sealant and the dope is the lubricant.

[second opinion]

Not sure what gas code you are using in your area but you might ask the inspector what code he is enforcing. Teflon tape is a good lubricant, and is not a problem in most jurisdictions. It does not have a chemical reaction with natural gas, or propane.

[HVAC Teacher]

I was always told that there is a possiblity of the tape breaking off and getting stuck under the valve seat. I heard it blew up a house when the spark came on. Probably an urban legend.

[big johnson]

I was always told that there is a possiblity of the tape breaking off and getting stuck under the valve seat. I heard it blew up a house when the spark came on. Probably an urban legend.

You hit the nail on the head. Regular Teflon tape, if wrapped on the first row of pipe threads, can shred and sluff pieces down the line. If you try the yellow stuff, you'll notice it has a heavier feel and doesn't come apart like the white stuff. Regular, white Teflon tape is illegal to use in Washington State on gas lines for that reason.

[makinmoney]

I like using "Blue Block" pipe dope.....I have used the Teflon based pipe dope and haven't had a problem with it.

[farmboy1]

[QUOTE=second opinion;1603026]Not sure what gas code you are using in your area but you might ask the inspector what code he is enforcing. Teflon tape is a good lubricant, and is not a problem in most jurisdictions. It does not have a chemical reaction with natural gas, or propane.


Where I'm located. It doesn't have to be code . If inspector doesn't want you to use a product ,you don't use that product. Aluminum tape for instance. Some Inspectors here will approve the tape without UL listing, some will not. Just do what they say & you won't get a hard time

[AtticAce]

strands. I believe the reason is correct about interfering with the gas valve operation. I do not believe this can happen in a modern gas valve, but the some of the old ones did not have inlet screens.

Inspectors usually are looking for something to fail, this one locked on to your tape. I had an inspector fail a 3 inch gas main because pipe dope was dripping off some of the joints. He wrote it up as gas piping leaking yellow material, I kid you not!

Do you want to know something really neat? In Philadelphia you do not need a permit to install a heating boiler of any size.

You do however need 2-3 licenses to install a warm air system, the third is needed to install an oil furnace. These are above your business licenses.
Just goes to show you the power of the plumbers union.
How about the code in Philly that says all new construction must have central cooling, this includes low cost housing? In Philly the poor have air conditioning, until it breaks.

[DPSwitch]

Where I'm located. It doesn't have to be code . If inspector doesn't want you to use a product ,you don't use that product.

The International Mechanical Code pretty much gives the building official the juristiction to fail anything he wants. So if the locality adopts the IMC ....thats the way it works.

[allstar08]

You hit the nail on the head. Regular Teflon tape, if wrapped on the first row of pipe threads, can shred and sluff pieces down the line. If you try the yellow stuff, you'll notice it has a heavier feel and doesn't come apart like the white stuff. Regular, white Teflon tape is illegal to use in Washington State on gas lines for that reason.

I thought it was, but when was it beginning to be enforced? I used it for years with pipe dope. I still see guys in the field using it for gas without being called on it.

[Special-K]

Gotta use the yellow here.

[tinknocker service tech]

i use just plain old prodope

i was told years ago by an old timer that all you need to make a proper connection is oil

he proved it also did an entire gas pipe job useing cutting oil on the threads and not one leak and raise the pressure to 80 lbs.

his exact words to me when i asked for some thread sealant were

if the threads are made properly and the dyes are good all you need is oil
take that fcking sealant and throw it the fck out and do the fcking job right and handed me a can of prodope

prodope thats it

[allstar08]

A guy I work with used to gas pipe in Vietnam and he said that when they run out of dope they use plastic bags, like the ones you get at the grocery store.