How to tap into propane (iron pipe) line

[dragoneggs]

I plumbed a propane BBQ to run off the house tank and also installed a garage furnace. Gave me reason to buy a couple tools. A manometer and also this handy gas sniffer that you can check on all your gas appliances.

HOME-FLEX Electronic Gas Leak Detector 11-810-001 - The Home Depot

The HOME-FLEX Electronic leak detector is designed to detect even small gas leaks. Built-in microprocessor easily detects natural, liquid propane, butane and methane gases. Red and yellow lights illuminate

www.homedepot.com

 

[rScotty]

You may not need a larger underground pipe from tank. You might just need to tee off before existing house secondary regulator and add another regulator for generator. But you need to have your propane supplier or heating contractor look at setup. They need complete list of all gas appliances max btu for house and generator. With this info they can estimate pipe sizing. The gas coming from tank primary regulator is probably 10 psi. You can move alot of gas at 10psi.

where i usually ran into issues is the houses up here are generally only supplied with 1/2” line from propane tank. If yours is really a 3/4” line, you may be ok.

I agree with that. Chances are that with a 3/4" line you can just tee into the existing high pressure line from the tank and add another low pressure regulator for the generator.

 

[gasman1075]

I appreciate all the helpful replies.

The generator is 142 cu ft per hour, 3.9 gph, 10-12 in water column. So would that be 355,000 btu? Let's call is 70 feet from main tank to generator supply, to add some footage for turning pipe down then back up. The regulator (2nd stage) is right at the location where it comes up out of the ground, about 5 feet from where the generator will sit.

Some suggested a new, dedicated regulator for the genset. This would be where the 3/4" comes up out of the ground into a T. If that is done, the existing regulator is in place for the pipe in the other direction-- going to a water heater 15 feet away. I don't have the btu's handy, but its a typical 40 gal gas water heater.

I don't know how you set line pressure. Does the propane company do that? Obviously, if increasing the line pressure makes running the genset possible, that is hugely more attractive than trenching!!

3.9 GPH is 360,812 BTU / HR. At 80' and low pressure ( 11'-13" WC) you would need at least 1" black pipe. At high pressure ( 10 PSI to a new second stage regulator ) at 60' 1/2 back would handle it. The second stage regulator needs to be at least 5' away from any source of ignition. At 5' from the second stage to the generator 3/4" black is plenty. Me I would run whatever size pipe the inlet is to the generator. The SS flex should have no more than a 3/8 offset Any installation like this needs to be pressure tested to 1.5 the max working pressure but no less than 3PSI for at least 10 minutes. It sounds like your regulator is in a good spot to plumb the generator. I would suggest upsizing the pipe after the second stage so you create a reservoir of gas feeding the generator. I instead of a sediment trap I use strainers on generators to filter any imperfections before it gets to the generator. The line pressure is set at the first stage and shouldn't be touched without permission of the LP company. Same with the second stage If CA allows homeowners to do this work I would suggest you let the LP company know so they can a. Do a gas check, b. then they can add a new appliance to the gas check. If its that close I would suggest you hire somebody. JMO

 

[plowhog]

The second stage regulator needs to be at least 5' away from any source of ignition. At 5' from the second stage to the generator 3/4" black is plenty. Me I would run whatever size pipe the inlet is to the generator.

That is good information. I can adjust the pad location slightly to ensure I have 5' of clearance between the second stage and the generator.

The generator has a 3/4" inlet/supply pipe. It requires the purchaser to screw in a 3/4 nipple through a pre-drilled hole in the case. Where the nipple connects, there is already a drip leg pre-installed inside the unit.

I will have the propane company make any adjustments to pressure. Regarding pipe upsize, is that to allow for an inrush sudden demand such as on generator startup? And do you typically go up one size (1") or even larger (1 1/4?)? I presume you maintain the upsized pipe for several feet, then downsize back to 3/4 where the flex connects to the generator? btw a 3/4" flex line was supplied with the generator-- maybe 8-10 inches long.

 

[gasman1075]

Yes the upsize at the generator is for start up most start on full throttle then cycle back. I would 90 out going back then flex ( is it stainless steel ? ) then union then nipple then full port ball valve such as a JOMAR then nipple then bell coupling 3/4 x whatever the reservoir pipe size is ( bigger is better ) then bell coupling at other end and 3/4 to second stage. On the outlet of the second stage you want as long a nipple as possible before any fittings that change direction. A Fisher R652 back mount was my favorite for generators because the inlet was on the bottom and the outlet was on the back so it changed the direction of flow for you with little pressure drop.

 

[Sberry]

They want the supply large to cover it but LP is 270 cf per gallon. This little genset does not use nearly 4 gallons an hour. I am running 350 chevy at 1/2 or 3/4 that runs that. To a home, a 3/8 copper tubing supplies 200K btu between stage 1 and 2 66 ft.

 

[gasman1075]

LP is 2516 btu / CF and 1 gallon = 91502 BTU so 142 CF/HR = 357,272 BTU or 3.90452 GPH

 

[PILOON]

In the '50's my dad had the first propane furnace installed in the area.
Every time it started with a small 'boom' and often opened the trap door leading to the cellar.
Plumbers were the installers back then.

Once on a job site I was asked to finish the floor installation as the flooring guy quit on the job.
The propane installation guy had attached the gas line to the bottom of the sub floor rather than on the sides of the joists.
As I was nailing the floor down a sudden odor of propane permeated the air.
Yep, a flooring staple pierced that gas line.
I called for immediate evacuation and opened all windows and doors.
LOL, no BOOM.

I sure have learned to respect propane and its codes but then having camps and propane heat, lighting, cooking and refrigeration etc you had no choice if you DIY'd and wanted to live.
Hey, we even once had a propane 'cooker toilet'. (Phew!) and even a propane 'instant water heater' as used in some RV's.
Then I once converted a propane baggage tug from propane to gas.
(Sold it and made decent profit.)

 

[gasman1075]

In the '50's my dad had the first propane furnace installed in the area.
Every time it started with a small 'boom' and often opened the trap door leading to the cellar.
Plumbers were the installers back then.

Once on a job site I was asked to finish the floor installation as the flooring guy quit on the job.
The propane installation guy had attached the gas line to the bottom of the sub floor rather than on the sides of the joists.
As I was nailing the floor down a sudden odor of propane permeated the air.
Yep, a flooring staple pierced that gas line.
I called for immediate evacuation and opened all windows and doors.
LOL, no BOOM.

I sure have learned to respect propane and its codes but then having camps and propane heat, lighting, cooking and refrigeration etc you had no choice if you DIY'd and wanted to live.
Hey, we even once had a propane 'cooker toilet'. (Phew!) and even a propane 'instant water heater' as used in some RV's.
Then I once converted a propane baggage tug from propane to gas.
(Sold it and made decent profit.)

vehicle conversions I have never done but everything else with LP and natural gas I have been doing since since 1980. But knees hips and back are shot from kneeling on concrete and wrestling boilers and tanks etc. so I teach at night and sell during the day. Its been a great industry and a decent living.

 

[jaxs]

In the '50's my dad had the first propane furnace installed in the area.
Every time it started with a small 'boom' and often opened the trap door leading to the cellar.
Plumbers were the installers back then.

Plumbers should be forbiden to work on anything past the gas stop valve or electric disconnect. They aren't trained so I don't understand why they are alowed to mess with it. My solution for those old booming appliances was extend the standing pilot accross all burners or larger than usual singles. I once did a furnace for a church that had paid multiple plumbers an absured amount of money trying to stop a furnace booming.