Unions on Black Iron / Fittings

jamiedolan · Sep 2, 2008

HI,

Are there any restrictions on the use on unions on a black iron gas pipe system? I know they must remain fully accessible, but beyond that, is there any reason not to use them? They make changes much easier when your dealing with a larger setup.

Is there a rule of thumb for how much distance a coupler, t, elbow, etc adds? I've always just measured to approximately where the I know the threads end. I just wondered if there is a way to do it, i.e. add 1" for a 1" fitting or something similar.

Thanks

Jamie

JerryWatson · Aug 5, 2009

Hi
According to the Uniform Mechanical Code, unions are only allowed at the gas meter and at each individual appliance. To avoid fit up problems, measure from end of a pipe to the center of the fitting you are going to install. In other words, thread one end of a piece of pipe, apply pipe joint compound (not Teflon tape), screw on a fitting, measure the length of pipe you need from the center of the fitting, mark and cut the pipe, thread it, and install it. Good luck!

Plumber101 · Feb 25, 2009

Jerry please post chapter and section of the UMC or UPC and version so I may look up that unions are only allowed at gas meters.

Unions and coupling bends can be used any where except when enclosed in walls where access can not be made with out tearing out the wall

Termite · Apr 13, 2008

I can't speak to the UPC or UMC, but I can tell you that the I-codes (IRC, IBC, IPC, IFGC) do not prohibit the use of unions anywhere they're needed. I've never seen a code that states otherwise, and would also be interested to see that posted. They're of course required at hard-piped appliances by the I-codes. They cannot be installed in inaccessible places.

Plumber101 · Feb 25, 2009

KC it's the same. The IPC and IMC is just like UPC and UMC except the Uniform code has more requirements incertain area.

For example UMC requires pans under drip pans HVAC in attic installs where IMC does not. Just simple stuff

Our local cities I work in just switched from International to Uniform.

Alot of benifits in doing so especially with CEU's

OH I'm not a great speller :laughing:

JerryWatson · Aug 5, 2009

UMC and UPC chapter and verse

Plumber101 said:
Jerry please post chapter and section of the UMC or UPC and version so I may look up that unions are only allowed at gas meters.

Unions and coupling bends can be used any where except when enclosed in walls where access can not be made with out tearing out the wall

Unfortunately, I have been retired for a bit now and no longer have my code books, but when I did, that was the rule. I know that the codes are continually being updated and new codes have been adopted so I can't speak for those. If my information is outdated or incorrect, accept my sincere apologies. I don't visit this planet much anymore because everything is changing so rapidly! :laughing:

Plumber101 · Feb 25, 2009

JerryWatson said:
Unfortunately, I have been retired for a bit now and no longer have my code books, but when I did, that was the rule. I know that the codes are continually being updated and new codes have been adopted so I can't speak for those. If my information is outdated or incorrect, accept my sincere apologies. I don't visit this planet much anymore because everything is changing so rapidly! :laughing:

No apologies needed. I was asking just incase I had missed something.

We're all in this together.....

Termite · Apr 13, 2008

Plumber101 said:
No apologies needed. I was asking just incase I had missed something.

We're all in this together.....

Yup! :yes:

majakdragon · Sep 16, 2006

Whether using unions anywhere besides appliance connections or meters is Code or not, the bottom line is that using them offers 3 possible points to leak rather than two. In Ohio, the gas companies frowned on this practice and they had the final say. Just a thought.

jamiedolan · Sep 2, 2008

majakdragon said:
Whether using unions anywhere besides appliance connections or meters is Code or not, the bottom line is that using them offers 3 possible points to leak rather than two. In Ohio, the gas companies frowned on this practice and they had the final say. Just a thought.

Thanks.

Yes, I do understand the extra point where they could leak. I plumbed up a new line for going out to my grill, re-did the pipe to the furnace, and installed a new line up into the kitchen for the gas cooktop.

The gas line in this house had been professionally installed back in 63. I thought I had smelled gas near some of the fittings, so I replaced those when I redid the Kitchen and the gas for the grill. Upon further investigation, I found that there was a leak at the first 90 after it came into the house. At that point, I decided every joint needed to be pulled, cleaned and have new compound applied, using 2 unions allowed me to leave all my stove / grill / furnace work in place.

The gas pipe is 1-1/4" where it comes into the house, it had previously had a reducing t on it that went to 1" and 3/4". I wanted the ability to put a tankless water heater on it in the future if I decided to. Neither the 1" nor the 3/4" were large enough to handle a tankless with there current load. So I changed out the reducing T to 2 new 1-1/4" T's. Leaving me the connection at the bottom, at 1-1/4" available for a future tankless without having to re-do any of the current system I am re-doing now.

The T on the top with the bushing in it will feed the 1" furnace / grill line.

I wasn't able to find a reducing T, hence the use of the busings. I wasn't even able to get a 1-1/4"X3/4" bushing, hence the use of 2 bushings to the 3/4".

Thanks again for the help.

Jamie

P.S. - KCtermite; I also replaced those running thread couplers with the correct couplers.

Termite · Apr 13, 2008

jamiedolan said:
P.S. - KCtermite; I also replaced those running thread couplers with the correct couplers.

Well done! :thumbsup::thumbsup::thumbsup:

Plumber101 · Feb 25, 2009

jamiedolan said:
Thanks.

Yes, I do understand the extra point where they could leak. I plumbed up a new line for going out to my grill, re-did the pipe to the furnace, and installed a new line up into the kitchen for the gas cooktop.

The gas line in this house had been professionally installed back in 63. I thought I had smelled gas near some of the fittings, so I replaced those when I redid the Kitchen and the gas for the grill. Upon further investigation, I found that there was a leak at the first 90 after it came into the house. At that point, I decided every joint needed to be pulled, cleaned and have new compound applied, using 2 unions allowed me to leave all my stove / grill / furnace work in place.

The gas pipe is 1-1/4" where it comes into the house, it had previously had a reducing t on it that went to 1" and 3/4". I wanted the ability to put a tankless water heater on it in the future if I decided to. Neither the 1" nor the 3/4" were large enough to handle a tankless with there current load. So I changed out the reducing T to 2 new 1-1/4" T's. Leaving me the connection at the bottom, at 1-1/4" available for a future tankless without having to re-do any of the current system I am re-doing now.

The T on the top with the bushing in it will feed the 1" furnace / grill line.

View attachment 13265

I wasn't able to find a reducing T, hence the use of the busings. I wasn't even able to get a 1-1/4"X3/4" bushing, hence the use of 2 bushings to the 3/4".

Thanks again for the help.

Jamie

P.S. - KCtermite; I also replaced those running thread couplers with the correct couplers.

Very nice job.

If I could make one suggestion though is take a rag and wipe off the excess of pipe dope around the fittings and on the pipe.

Other than that it looks like a pro job.

Termite · Apr 13, 2008

Not to be a critic Jamie because you do beautiful work, but something to be prepared for when you get this work inspected...

Section G2414.10.4 of the IRC (403.10.4 of the IFGC) prohibits the use of bushings to reduce/increase pipe size. Note 4 of that section: Cast iron bushings shall be prohibited. Can't use 'em.

Don't ask me why, but the code requires bell-type reducers. I'd have a hard time turning it down personally.

jamiedolan · Sep 2, 2008

thekctermite said:
Not to be a critic Jamie because you do beautiful work, but something to be prepared for when you get this work inspected...

Section G2414.10.4 of the IRC (403.10.4 of the IFGC) prohibits the use of bushings to reduce/increase pipe size. Note 4 of that section: Cast iron bushings shall be prohibited. Can't use 'em.

Don't ask me why, but the code requires bell-type reducers. I'd have a hard time turning it down personally.

EDIT: See next post, I don't think these are cast bushings.

Wow that seems so weird to me. Thanks for letting me know that it could be an issue.

Any idea why they sell these bushings for black pipe sine they are not compliant? Is there some approved use for them? It's my fault for not checking, but seeing a black reducing bushing with all the other black fittings at the store didn't give me any reason to question, it's legality.

Well if it has to be changed, ill have to change it.

Thanks again,
Jamie

jamiedolan · Sep 2, 2008

thekctermite said:
Note 4 of that section: Cast iron bushings shall be prohibited.

I think these are actually labeled as Black Steel on the packages for the bushings.

If they are steel bushings and not cast iron, is there anything to prohibit there use?

Jamie

Plumber101 · Feb 25, 2009

OH you peesky inspectors.........

IMO what you did is fine and I don't believe that the bushing you used are cast.

KC is right about cast bushings in the IFGC and I even loked it up in the UPC same wording.

I don't use bushings unless space is an issure but I have never been failed for using black iron bushings.

Best that you can do is talk with your local code office for advice.

kenmac · Feb 26, 2009

jamiedolan said:
I think these are actually labeled as Black Steel on the packages for the bushings.

If they are steel bushings and not cast iron, is there anything to prohibit there use?

Jamie

The code doesn't say anything about cast bushings or black iron bushings... It says bushings which would include bushings of any type material. For this reason . I choose not to use them.. I don't want to remove & re-pipe when I get turned down...This is the reason I only use bell reducers, reducing t's , ells, etc,

Termite · Apr 13, 2008

Kenmac, I quoted code verbatim in my post. Code prohibits cast iron bushings specifically.

Unions on Black Iron / Fittings

jamiedolan

DIY'er

JerryWatson

Registered

Plumber101

GC/Master Plumber/Mech

Termite

Registered User

Plumber101

GC/Master Plumber/Mech

JerryWatson

Registered

Plumber101

GC/Master Plumber/Mech

Termite

Registered User

majakdragon

Registered

read more

DIY'er

Termite

Registered User

Plumber101

GC/Master Plumber/Mech

Termite

Registered User

jamiedolan

DIY'er

jamiedolan

DIY'er

Plumber101

GC/Master Plumber/Mech

kenmac

HVAC / Plumbing

Termite

Registered User