Gas Regulator Vent Location

[600SL]

I have a question about the location of the gas regulator vent. I have two regulators, one for my propane boiler and one for my generator. I was told that the vents had to be 10' from the generator and that's where they are now. But I would like to build an outside shed for my compressor and would like to put that shed right next to the two vents. Is there any limitation as to where a compressor shed can be placed in relation to the gas vents. The two vents are shown at the end of the black pipes in the picture below. I would like to place the shed just to the right of the last vent. The shed will not be fully enclosed as the back of it will be open but up against the wall. Also is there any issues with proximity to the LP tanks?

Thanks
John

 

[Firebrick43]

Yes there is. Because of the contactors I wouldn't put neither the vents nor the 120gal/420lbs cylinder within 10 feet of the compressor shed

https://www.regoproducts.com/content/dam/pes/pdfs/L-545_Servicemans_Manual.pdf

page 15

 

[T444e]

I am sure it is addressed in NFPA 54, but never had to look it up. When I was involved with with projects requiring the regulator(s) to be vented outside, the EOR showed routing and termination on the drawings.

 

[Firebrick43]

I am sure it is addressed in NFPA 54, but never had to look it up. When I was involved with with projects requiring the regulator(s) to be vented outside, the EOR showed routing and termination on the drawings.

NFPA 54 is inside the building, not outside. That is NFPA 58 as sited above

 

[Firebrick43]

How big of generator do you have? A 120 gal tank won't give you much run time on an 8-10k genny

 

[T444e]

I saw the diagram was dealing with DOT cylinders. I don't recall ever referencing NFPA 58 or even seeing it referred in specifications, even when bringing gas into the building from a remote located meter.

From a quick look, it appears to me, NFPA 58 covers LPG. I was assuming OP was working with natural gas. Read too fast the first time, didn't catch the LP tanks.

 

[T444e]

NFPA 54 is inside the building, not outside. That is NFPA 58 as sited above

Off topic, but I'm going to have to look at NFPA 58, you piqued my interest. I did do a couple of underground, inside plant NG projects that, if I remember correctly, didn't reference NFPA at all. They were utility projects, all fully designed and engineered, and were not pipeline as they were inside plant and we were hydro-testing near 3000 psig.

 

[600SL]

How big of generator do you have? A 120 gal tank won't give you much run time on an 8-10k genny

Generator is 26KW I have 2 120 gal tanks. The other one is just to the right of the one shown in the picture.

 

[600SL]

Yes there is. Because of the contactors I wouldn't put neither the vents nor the 120gal/420lbs cylinder within 10 feet of the compressor shed

https://www.regoproducts.com/content/dam/pes/pdfs/L-545_Servicemans_Manual.pdf

page 15

Thanks for this. Looks like I'm going to have to re-plan.

 

[fitter30]

Have to also think about the snow height. If either or both regulators hunt ( can't seem to hold pressure steady the vent line is to small). Use a union on vent line at reg for service. LP is heavier than air and will settle.

 

[600SL]

Have to also think about the snow height. If either or both regulators hunt ( can't seem to hold pressure steady the vent line is to small). Use a union on vent line at reg for service. LP is heavier than air and will settle.

The lower vent line was installed by the gas company and both were inspected so I guess its good and its the same height as the one on the main house. New plan is to extend the gas vents to exit by the propane tanks that would make the longest one 24 ft. Or is there any limit to the length of the vent pipe?

 

[Firebrick43]

If exceeding 20’ your supposed to step up one nominal pipe size

 

[600SL]

If exceeding 20’ your supposed to step up one nominal pipe size

20 would work. No issues with the vent being near the tanks?

 

[Firebrick43]

20 would work. No issues with the vent being near the tanks?

No, there is a vent already there on the high pressure regulator

 

[600SL]

No, there is a vent already there on the high pressure regulator

Thanks Looks like I'm back to having a plan

 

[600SL]

Yes there is. Because of the contactors I wouldn't put neither the vents nor the 120gal/420lbs cylinder within 10 feet of the compressor shed

https://www.regoproducts.com/content/dam/pes/pdfs/L-545_Servicemans_Manual.pdf

page 15

Looks like I may have a problem with the regulator position as well with the 5 ft requirement? What is considered the source of ignition in this case. If the compressor motor and contactor is on the right side 5 ft should not be a problem. But if the outside wall needs to be 5 ft away than that is a problem. For reference the compressor shed will look something like the second picture and will have a 4' x 4' footprint.

 

[Firebrick43]

Looks like I may have a problem with the regulator position as well with the 5 ft requirement? What is considered the source of ignition in this case. If the compressor motor and contactor is on the right side 5 ft should not be a problem. But if the outside wall needs to be 5 ft away than that is a problem. For reference the compressor shed will look something like the second picture and will have a 4' x 4' footprint.

"5 foot minimum from Relief Discharge to a source of ignition or mechanical air intake"

The relief discharge is the vent on the regulator. If you install the vent kit correctly now the "relief discharge" as at the end of the vent kits pipe/screen not the regulator itself.

So if your tanks are 10 feet away from your compressor shed, and your secondary regulator vent kits terminate by the tank, then your 5 foot minimum is maintained even if your compressor is only 4' from the regulator itself.

 

[600SL]

"5 foot minimum from Relief Discharge to a source of ignition or mechanical air intake"

The relief discharge is the vent on the regulator. If you install the vent kit correctly now the "relief discharge" as at the end of the vent kits pipe/screen not the regulator itself.

So if your tanks are 10 feet away from your compressor shed, and your secondary regulator vent kits terminate by the tank, then your 5 foot minimum is maintained even if your compressor is only 4' from the regulator itself.

Thank you.

That's good to know. I may have to cheat a little on the lower vent line to about 22' long. I will probably step those extensions up to 1".