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LP gas tank regulatorLP Gas, Propane Gas, & Natural Gas Pressures & Pressure Settings

  • POST a QUESTION or COMMENT about LP gas pressure, propane gas pressure, and natural gas pressure in piping, at regulators, at appliances

LP or Propane Gas Pressures & Natural Gas Pressures at common appliances:

Here we give the standard pressure ranges and pressure settings for LP gas, propane gas, and natural gas fuels, including pressures found in the distribution service piping, in the in-building gas piping, and at gas fired appliances such as gas stoves, clothes dryers, furnaces, boilers, and LP gas or natural gas fired water heaters.

What are the common operating pressures of natural gas and LP or "liquid petroleum" gas in the building gas piping and at the appliance?

Since there several ways that people express gas pressures we include more than on description of common LP gas or natural gas system operating pressures in this article.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

What are the Typical LP or Natural Gas Set Pressures Found in Residential Systems

Bosh Gas Regulator for a gas cooktop (C) Daniel FriedmanArticle Series Contents

Natural Gas Appliance Operating Pressures in WC, millibars, Pascals, PSI or ounces of pressure

A common operating pressure for natural gas appliances is around 7 inches of water column (WC) or re-stating this in equivalent measure, that's 14.9 millibars or 1743 Pascals or Pa, or about 0.25 psi (pounds per square inch) or about 4 ounces of pressure per square inch.

See NATURAL GAS APPLIANCE PRESSURES for details.

LP or Propane Gas Appliance Operating Pressures in WC, millibars, Pascals, PSI or ounces of pressure

A common operating pressure for liquid petroleum or LP gas appliance is 10" - 11" of water column (WC) or re-stating this in equivalent measures, that's 27.4 millibars or 2491 - 2739 Pascals or Pa, or about 0.36 - 0.40 psi or about 5.78 to 6.36 ounces of pressure per square inch.

See LPG & PROPANE APPLIANCE PRESSURES for details.

Density of Propane vs Natural Gas

From these three data points you can see that natural gas is lighter than air while propane is heavier (more dense) than air. The density of lighter-than-air gases (natural gas) inside of a closed vertical pipe will be lower at higher heights than at the base of the pipe.

Some details are at GAS PRESSURE vs BUILDING HEIGHT

This article continues with more detailed information about the typical pressures and other properties of Butane or of LP gas - liquid propane or "bottled gas", and in a separate section we continue with the properties of natural gas or "piped in gas" used as appliance fuel in buildings.

Typical LP Gas Pressures & Volumes in Residential Appliances

Typically a manufacturer of a home appliance such as gas cooktop will indicate that the LP gas pressure supplied to the appliance regulator inlet cannot exceed 14" WC for LP gas. Manufacturers also say that the inlet gas pressure must be at least 1" WC greater than the regulator output pressure setting.

Example Gas Cooktop Pressure Requirements

Finally, just a couple of data points as examples, again borrowing from one of Bosch's Gas Cooktop installation guides (NGM80 series using model NGM8065UC),

  1. The minimum gas supply pressure 

    must be 1" water column (0.036 psi or 249 pa or 2.5 Millibars ) above the manifold pressure printed on the appliance data plate
  2. The maximum gas supply pressure 

    must not exceed 14" water column (0.5 psi or 3487 pa or 34.9 Millibars)
  3. The natural gas supply pressure 

    for this specific appliance, your appliance may be different should be 7" water column (0.25 psi or 1744 pa or 17.4 Millibars)

    [ the instructions say 14.9 millibars which looks to me like a possible error as 14.9 millibars = about 6" of water column (0.22 psi) - ed.]
  4. The Propane or LP or LPG gas supply pressure

    for this specific appliance, your appliance may be different should be 11" water column (0.40 psi or 2740 pa or 17.4 millibars)

Natural Gas pressures are described in detail

at NATURAL GAS APPLIANCE PRESSURES

It is important to separate the LP gas (propane gas) pressures that are exerted inside the LP gas storage tank or cylinder from the LP gas pressures that should be delivered to individual appliances.

Watch out: keep in mind that piped-in natural gas found at homes where that service are available will be at different pressures, use a different regulator, and requires changes or adjustment at any appliances that are being changed from LP or Propane gas to Natural gas, or vice versa.

A typical gas regulator used on appliances themselves can be converted to regulate either LP or natural gas delivery pressure in the range required by the appliance over a range of 3-15 inches of water column (WC). Some outdoor gas appliances require higher operating pressures (up to 60 psi). Details are

at CONVERT NATURAL GAS to LP GAS / PROPANE

Why do we Need a Regulator on LP or Propane Gas Systems?

Photograph of a natural gas regulator on a furnaceThe gas pressure delivered to a heating appliance (gas range, clothes dryer, gas heating furnace, gas fired water heater, etc) needs to be both constant and at the proper pressure for that appliance.

Because of varying outdoor temperatures, the LP gas pressure inside the storage tank may be as low as 10 psi in freezing weather or as high as 200 psi with the tank exposed to sunlight in hot weather.

And in natural gas fuel systems the gas pressure delivered from the gas main in the street can also vary widely by area, season, time of day and for other reasons.

The regulator(s) have to keep gas flowing to the appliance(s) at that pressure even as pressure in the storage tank changes and even when the number of appliances consuming gas changes (as devices turn on and off in the building).


Gas pressure and gas flow rate at individual appliances in a building needs to be maintained at the level needed by each appliance.

See GAS REGULATORS & APPLIANCE / HEATER CONTROLS for details.

What is pressure LP or LPG "liquid petroleum" gas inside the gas tank?

This topic is now in a separate article

at LPG PROPANE TANK PRESSURES

There is some confusion, even among LP gas service technicians about just what is the pressure inside the gas containers they deliver to or fill at properties. Perhaps this is because the gas laws explain that the vapor pressure of LP-gases varies as a function of temperature.

See BOYLE's LAW discussed at this website.

Gas Cylinder or Tank Regulators: Readers concerned with installing, inspecting, or testing LP Gas regulators which are found on outdoor above ground or buried gas cylinders used for storage of LP Gas on site should also

see GAS REGULATORS for LP TANKS

Effects of Building Height or Piping Length & Diameter on Gas Delivery Flow Rates & Pressures

This topic has moved to a separate article

at GAS PRESSURE vs BUILDING HEIGHT

Articles relating height of a column of water or gas, building height, water pressure, chimney draft, gas pressure include

 

Typical Natural Gas Pressures found at Private Homes & At Appliances

The American Gas Association offers this explanation of typical natural gas pressures, Quoting with significant editing and paraphrasing:

Natural gas runs from the main into a home or business in what's called a one-inch or smaller-diameter natural gas service line. In the service line gas pressure varies by community and other factors, flowing at a pressure range of over 60 pounds to as low as ¼ pound.

When the gas passes through a customer's gas meter and moves inside the home, gas travels to equipment and appliances through piping installed by the home-builder and owned by the customer where it reaches the individual natural-gas-fired appliance(s).

At the customer's gas meter the incoming natural gas passes through another regulator to reduce its pressure to under ¼ pound (0.25 psi) if this is necessary. (Some services lines carry gas that is already at very low pressure.) This is the normal pressure for natural gas within a household piping system.

When an appliance such as a natural-gas furnace or stove is turned on, the gas pressure is slightly higher than the air pressure, so the gas flows out of the burner and ignites in its familiar clean blue flame. [1]

Watch out: keep in mind that piped-in natural gas found at homes where that service are available will be at different pressures, use a different regulator, and requires changes or adjustment at any appliances that are being changed from LP or Propane gas to Natural gas, or vice versa.

Details are at CONVERT NATURAL GAS to LP GAS / PROPANE

The following example of LP, Propane, and Natural Gas appliance pressures are excerpted from that article:

Example Gas Cooktop Pressure Requirements

Finally, just a couple of data points as examples, again borrowing from one of Bosch's Gas Cooktop installation guides (NGM80 series using model NGM8065UC),

  1. The minimum gas supply pressure 

    must be 1" water column (249 pa) above the manifold pressure printed on the appliance data plate
  2. The maximum gas supply pressure 

    must not exceed 14" water column (3487 pa or 34.9 Millibars)
  3. The natural gas supply pressure 

    for this specific appliance, your appliance may be different should be 7" water column (1744 pa) [ the instructions say 14.9 millibars which looks to me like a possible error as 14.9 millibars = about 6" of water column - ed.]
  4. The Propane or LP or LPG gas supply pressure 

    for this specific appliance, your appliance may be different should be 11" water column (2740 pa or 17.4 millibars)

LP or Propane Gas Appliance Pressures are given in detail

at LPG & PROPANE APPLIANCE PRESSURES

Gas delivery pressures drop in long or small diameter piping runs

Despite the unmeasurable effects of gravity on gas flow in LP or natural gas piping systems, there can be gas flow rate or delivery rate problems due to the pressure drop in long gas piping runs especially with smaller diameter gas piping.

Indeed there are often LP or NG gas flow rate and pressure delivery rate problems in long gas piping runs especially of small-diameter piping systems carrying gases (not liquefied LPG or LNG).

If we are talking about the delivery of appliance pressure (0.4 psi) and whether or not adequate LP gas is being delivered, we would consider the length of piping, even horizontally, as well as the pipe diameter, as well as any gas regulators in that routing.

In that case we would use a primary LPG pressure regulator at the tank to delivery say 10 psi into the gas piping system and we'd step that pressure down to 0.4 psi at or close to the appliance.

See GAS REGULATORS, TWO STAGE

Separately at WATER PRESSURE MEASUREMENT- we discuss the problem of calculating (or measuring) the pressure exerted by a vertical column of a substance (we use water) focusing on pressure at the bottom of the column (a starting point).

In the article above we mention that LP gas operating pressure for typical residential gas fueled appliances is is 10" of water - which is equivalent to about 0.36 psi and which we round-up to 0.4 psi. That is to say, the 0.4 psi figure you cite from our article is the typical operating pressure of LP gas appliances, NOT the pressure of the LP gas (vapor above the liquid) in an LP gas storage tank.

In the storage tank the LP gas vapor pressure ranges from 0-200 psi LP gas pressure depending principally on temperature (and of course having some liquid LPG in the tank. Typical pressures in the tank are at 10 psi (freezing weather) up to about 200 psi (very hot weather and a sun-exposed LPG tank).

You'll see in that article that indeed the temperature effects on LP gas delivery pressure are important in potentially cold-climates.

Reader follow-up:

With natural gas being lighter/less dense than air, I never thought that getting gas up a pipe would be a problem – turn the appliance on and the gas would want to naturally rise and escape.

But with LPG being heaver/more dense than air I always thought that there will be a limit that the gas will rise up the pipe before it stops rising.

Using water as an example (and not including all the different losses) if we had a pump delivering water at 0.4psi (about 2.75kpa) than the water would only rise up the pipe 26.9 meters. Would that not be the same with the LPG?

I’m starting to further understand the theory behind your calculations but am not yet totally convinced (maybe that’s just the plumber in me talking)

I guess the question should be asked differently.

At what height above the regulator will the gas no longer flow?

Keeping the number simple and assuming 50/50 propane to butane with an approximate weight of 2kg/m3 and the vapour pipe being 100mm (to overcome the system losses assumed) and a length of 400m I calculate the weight of the gas to be 628kg. being that its denser than air this weight would be exerted on the regulator. Would that much weight on the regulator diaphragm effect the regulator?

This is all new to me and I thank you in advance for any input.

Again keep up your good work with the website.

Reply:

The answer to your question as re-phrased is

at EFFECTS of building HEIGHT on GAS PIPING SYSTEMS

LP Gas Pressure Testing Procedure for Leak Detection

Reader Question: what is the test pressure used when testing an LPG line?

2016/04/01 Anonymous said:
newly commissioned lpg line what is the required pressure to test the line

Reply: minimum 3 psi, or 1.5 x the gas system's design pressure (low pressure gas testing)

Anon:

Gas systems may be tested at low pressure for low pressure propane installations such as those found at a typical home using LPG. A different, high-pressure gas test procedure is also described.

NFPA 54 (2006), 8.2.3 states that "Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the piping system shall be tested for leakage

. If leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made.

Low pressure gas leak tests of the gas piping

This test is performed with a pressure gauge installed on the "downstream" side of the final gas pressure regulator. It is testing the building's gas piping and gas appliances for leaks.

When pressure tests are performed on LPG piping, typically the system is sealed, a pressure gauge is installed, and the system is pressurized to 1 1/2 times the maximum design-operating pressure of the system OR a minimum of 3 psi. In some procedures the test period is brief: just 10 minutes for a residential building.

But the pressure test interval is increased by 1/2 hour for every 500 feet of piping (that's more likely to occur in a commercial installation).

If the pressure drops during the test period then tools or solutions are used to find the point of gas leakage. Leak testing might be by soap type solution, use of a combustible gas analyzer, or other means.

If the calculated test pressure of 1.5 x the design pressure would exceed 125 psi, then the test pressure should not exceed an amount greater than 50 percent of the pipe strength.

In a low-pressure LP gas system test, the appliance shutoff valves are "ON" (presuming that the appliances are installed) in order to assure that the appliance automatic gas shutoff features are working properly.

High-pressure gas leak tests between the LPG container and the first stage regulator

High pressure tests are made using a 300 psi gauge installed between the gas container (LPG) and the first stage regulator. The gas valve is opened for three seconds and then closed tightly. The system is bled down by at least 10 psi and then tested for 3 minutes, watching for a pressure drop.

A separate test can check for leaks at the gas regulator itself: a 30 psi gauge is installed at the outlet of the first stage regulator. With the pressure gauge installed, the LPG tank's gas valve is opened for 2-3 seconds, just to pressurize the regulator and test gauge. The system is bled down by at least 5 psi and observed for 3 minutes to watch for a pressure drop.

Watch out: these general gas leak test descriptions are for illustrative purposes and are not technically complete, detailed, nor exhaustive. Check with the gas testing specifications required where the gas installation is to be tested, and check the gas testing recommendations of the equipment manufacturers.

Watch out: WVPGA (2011) notes that the gas pressure test medium should be air or an inert gas. Never use oxygen.

...


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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2023-01-30 by Anonymous

@InspectApedia Publisher,

Thank you for the prompt and informative response. You are correct that my supplier was not very articulate in explaining what was going on. The supplier's contract and invoices were not helpful either. I found that your explanation was vert helpful and it led me to this which is also very helpful:

I am going to provide my supplier with this link so it can update its documentation to be more explanatory. Thanks again.

[Mod- disallowed link removed but copy can now be found at]

FUNDAMENTALS of PRESSURE & TEMPERATURE MEASUREMENT [PDF]

On 2023-01-29 by InspectApedia Publisher - propane volume corrections for cold weather

@Robert Lande,

Since 1 pound per square inch of pressure equals 27.78 inches a 2 pound regulator would be delivering pressure at about 55 inches of water column.

That is 5 times higher pressure than your 11 wc that they supplier mentioned.

We have no information at all about what's installed in your building, what equipment, at what BTU consumption rate, and using what regulators, but I'd expect a high pressure regulator at the tank to deliver pressure that's stepped-down by regulators at the individual gas-burning equipment.

I speculate that they're trying to say that you are running at high pressure and consuming more gas.

But you're quite right that **IF** gas pressures are identical then a cubic foot of gas at a specific pressure will be unchanged.

Further, "gallons" of propane is a liquid measure that doesn't change.

I suspect that the person you spoke with understands this topic better than we do, but perhaps wasn't an English major.

1 cubic foot propane = 0.0278 gallons propane - AT 60 degrees F. The gas industry standard reference temperature of 60°F is universally recognized as the base reference point for liquid propane volume correction.

Expressing this another way, there are 36.65 cubic feet of propane in a liquid gallon.

If your propane tank is filled during very cold weather, the drop in temperature will have reduced the liquid volume of propane in the tank (even though the total cubic feet of gas it would produce is un-changed). So when the driver may have delivered more LPG in cold weather than would have been delivered in warm weather for two cases in which the actual cubic feet of gas available out of your propane tank was otherwise the same.

In other words, a fill up in cold weather might seem to show that you used more cubic feet of gas than you really did. Instead, some of the "drop" of volume in the LP tank will simply be due to the outdoor temperature drop, not to gas consumption.

But nevertheless, when the driver "filled" your LP tank in cold weather, the volume they put into the tank is what they're going to use as a basis for billing you.

Think of it another way: when you get a delivery of 1 gallon of liquid propane in very cold weather, you're actually getting a delivery of MORE cubic feet of propane gas than if that same gallon was delivered in hot weather.

They're trying to explain that to you.

For this discussion, a "significant" temperature drop at your propane tank would be one of 20 degF or more.

Here is what one propane expert source says:

Propane delivery trucks all have meters that measure the amount of propane pumped into consumer tanks. These meters include a volume correction device known as an automatic temperature compensator.

The temperature compensator takes into account the temperature of the liquid propane running through the meter and automatically adjusts to correctly deliver the amount of propane that the consumer ordered.

By law, these devices are required to be re-calibrated and are adjusted based on the temperature of the liquid at the time of calibration. When a delivery of propane is made to your home or business, know that the amount you paid for is the amount you are actually getting. - Propane101, retrieved 2023/01/29, original source: https://www.propane101.com/propanevolumecorrection.htm

Copy here at

PROPANE VOLUME CORRECTIONS for COLD WEATHER [PDF]

On 2023-01-29 by Robert Lande

My. home is heated by propane. I am concerned that my gas meter may not be measuring the usage (in gallons) correctly.

For example, I received an invoice that indicated that I had used 70 CF of propane (expressed in 100s of cf). The invoice converted this to 214.9 gallons used. Conversion factor = 3.07 I asked the supplier why the conversion factor was not 2.76.

The supplier indicated that this was because I have a 2 lb regulator instead of a 11 wc regulator. This makes no sense to me. It seems that a cf = a cf regardless of the pressure of the gas.

On 2023-01-22 by InspectApedia Publisher - Viking gas range pressure regulator

@Michael Hettrich,

Here is what Viking says in a typical Viking gas range installation manual (check your specific range model and IO manual)

Pressure Regulator:

• All heavy-duty, commercial type cooking
equipment must have a pressure regulator
on the incoming service line for safe and
efficient operation, since service pressure
may fluctuate with local demand. External
regulators are not required on this range
since a regulator is built into each unit at
the factory. Under no condition bypass this
built-in regulator.

• Manifold pressure should be checked with
a manometer, natural gas requires 5.0”
W.C.P. and LP gas requires 10.0” W.C.P.
Pressure Regulator:

• All heavy-duty, commercial type cooking
equipment must have a pressure regulator
on the incoming service line for safe and
efficient operation, since service pressure
may fluctuate with local demand. External
regulators are not required on this range
since a regulator is built into each unit at
the factory. Under no condition bypass this
built-in regulator.

• Manifold pressure should be checked with
a manometer, natural gas requires 5.0”
W.C.P. and LP gas requires 10.0” W.C.P.

So I'm unclear about what your HVAC guy requires.

I'd give the company a call.
Viking Range Corporation
111 Front Street
Greenwood, Mississippi 38930 USA
(662) 455-1200

1-888-VIKING1 (845-4641)
Web: vikingrange.com

Source:

VIKING GAS RANGE INSTALLATION MANUAL [PDF]

On 2023-01-21 by Michael Hettrich

My HVAC guy said that I need to have a special regulator installed on my gas range because the new package unit we had installed requires an increased gas flow. what type of regulator is this? The stove is a viking 36" gas range.

On 2023-01-05 by InspectApedia Publisher

@Ed,

I don't know for sure but in concept, Increasing the pipes diameter of the piping In any portion and particularly in the longer portion of any run will improve the flow rate.

On 2023-01-05 by Ed

@InspectApedia Publisher, thanks for the link and the reply. I was looking at doing 3/4 as the main line and keeping the 3/8 for the short runs to the appliances, do you think that should work for my pressure issues?

On 2023-01-05 by InspectApedia Publisher - upgrade the main supply line to a larger gas line

@Ed,

I suspect you need a larger gas line.

See details at GAS PRESSURE FLOW INADEQUATE

and let me know if you try that and what are the results.

On 2023-01-05 by Ed

I have a 50ft run of 3/8 copper flexible tubing for my LP. The appliances in order of position on the run are dryer, stove, and water heater. At the regulator it is 13 WC.

With all other appliances off I check at the end of the run at the water heater and I'm getting the same. When the dryer turns on it drops to 5.5 WC at the end of the run. With only 2 burners on the pressure drops to 0.

In your opinion could there be an obstruction or just an issue with the size of the pipe? If that is the case do you have a recommendation on what size I should upgrade the main supply line to? Thanks in advance for your help.

On 2022-12-29 by InspectApedia Publisher - what is the Emergency Exposure Limits for low pressure in natural gas valves?

@adam,

please see

GAS EXPOSURE EFFECTS, TOXIC

GAS EXPOSURE LIMITS & STANDARDS

and let me know if those articles leave you with further questions

On 2022-12-29 by adam

what is the Emergency Exposure Limits for low pressure (7w.c/4oz) in natural gas valves? Is there an industry standard or code?

On 2022-09-06 by InspectApedia-911 (mod) - convert backup Generac generator to a tri-fuel

@Barry,

Most Generac backup generators, permanently-installed models, are hooked up to an LP gas or natural gas fuel supply. But the company does have models that can operate on LPG, natural gas, or diesel fuel.

You'll want to identify the specific Generator model you have installed, then contact the company to ask if that model generator can in fact be operated with multiple different fuels.

Contact Generac at

24/7/365 CUSTOMER SUPPORT
United States & Canada:
888-GENERAC (888-436-3722)
International: 1-262-544-4811

See details at

BACKUP ELECTRICAL GENERATORS

On 2022-09-06 by Barry

I want to convert my backup Generac generator to a tri-fuel.

how do I tell what pressure I need?

some conversion kits are different.

On 2022-06-21 by InspectApedia (mod) - stove wouldn't light, but gas coming to the regulator

@Dexter Mc Clean,

If you smell gas at the burner then the problem is more likely the igniter

see COOKTOP IGNITER REPAIR

On 2022-06-20 by Dexter Mc Clean

My stove wouldn't light, but there's gas coming to the regulator, could the regulator be bad

gas regulator (C) InspectApedia.com Dexter

On 2021-07-23 by danjoefriedman (mod) - normal house side of the regulator pressure of natural gas

@Daniel Johns,

Above on this page please see

Typical Natural Gas Pressures found at Private Homes & At Appliances

where all of those NG pressures are described

On 2021-07-23 by Daniel Johns

what is the normal house side of the regulator pressure of natural gas


On 2021-05-06 by danjoefriedman (mod) - what should the supply pressure to be to a commercial boilerhouse?

@kev JONES,

Kev: I'd like to be more useful but don't know enough of what you're asking: "commercial boilerhouse?"

First: the delivery gas pressures are different between piped in natural gas and propane (LP gas);

In addition, a commercial boiler may require higher pressures than the standard ones listed on the page above.

You'll need to look at the data for the gas equipment being served.

On 2021-05-06 by kev JONES

what should the supply pressure to be to a commercial boilerhouse

Question: How much pressure should be in a household gas line

(Sept 18, 2015) judy said:

How much pressure should be in a household gas line

Reply:

The gas line in the house should be at a pressure no more than the maximum rated input pressure on the appliance regulators in the building. For an LPG system in a typical residence that might be 0.5 psi.

Please see the article above on this page and let me know what questions remain.


...

Continue reading  at GAS REGULATORS & APPLIANCE / HEATER CONTROLS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see GAS PRESSURES LP & NATURAL FAQs - questions & answers posted originally on this page

Or see these

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GAS PRESSURES LP vs NATURAL GAS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


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