# Natural gas pressure gauge



## Maximumplumbing (Nov 6, 2010)

I'm looking at a gas job, it's to install a supply for a generator. I'm wondering what you guys use as some type of gauge to check the existing pressure of the existing gas line. I'm told its high pressure and that its plenty to supply the generator, but I'd like to test it myself so I can determine the right regulator to use. Any ideas on an accurate and quality gauge for this, and to also double check for leaks prior to firing things up. What do you guys use?


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## OldSchool (Jan 30, 2010)

A manometer... Get yourself a digital one ...

Then leak detector soap and water or do a pressure test..


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## Fullmetal Frank (Jul 11, 2012)

I'd get a gauge for gas and galv reducer and tie it into the line, with a tee.


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## Maximumplumbing (Nov 6, 2010)

How about this one?

http://www.amazon.com/UEi-Instruments-EM151-Electronic-Manometer/dp/B000OUV2D0


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## RW Plumbing (Aug 16, 2010)

Forgive my ignorance, how would you even use that. Seems like something I should know..


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## TX MECH PLUMBER (May 27, 2011)

It's a Mano meter It has a female brass fitting in the top of it with a clear tube. Like from a fish tank


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## TX MECH PLUMBER (May 27, 2011)

Maximumplumbing said:


> How about this one?
> 
> http://www.amazon.com/UEi-Instruments-EM151-Electronic-Manometer/dp/B000OUV2D0


Yep


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## Maximumplumbing (Nov 6, 2010)

Or this one. I've never used anything like these, so any info is appreciated. 

http://www.amazon.com/UEi-EM201-Dif...343878&sr=1-9&keywords=manometer+gas+pressure


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## TX MECH PLUMBER (May 27, 2011)

When I was green we tested with a water column gauge it had Mercury in it. Now I use a gauge with wc and psi. It only goes up to 5psi very sensitive gauge. We have a Mano but only use it when setting new equipment or if we need to know the residual pressure after a gas fired equip is running. And maybe starving a diff piece of equip


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## RW Plumbing (Aug 16, 2010)

TX MECH PLUMBER said:


> It's a Mano meter It has a female brass fitting in the top of it with a clear tube. Like from a fish tank


So you screw the fitting into the pipe and plug the meter into the hose off the end? I know cyclone heaters need a gauge like that to diagnose too. Might be worth picking one up.


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## TX MECH PLUMBER (May 27, 2011)

Yea. Hose from meter to a tee or fitting. The meter comes with 1/8 1/4 3/8 barbed fittings barbed in one end threaded on the other end.


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## Gettinit (May 9, 2012)

I love my dual Dwyer manometer. What are they calling high pressure? 2#, 5#, 10#...Get a two piece gas regulator and get it sized with the right spring and oriface from the local dealer/rep. A regular gauge sized properly can be screwed into a drip leg somewhere temporarily if you don't do this type of thing often.


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## RW Plumbing (Aug 16, 2010)

Now what's the story on the dual vs single. What can the dual do the single can't?


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## UN1TED-WE-PLUMB (Oct 3, 2012)

You can tell the gas pressure by looking at the system if you know what to look for. If its high pressure it probably means its 2psi. The regulator at the meter will have a yellow sticker that says 2 psi and it will either be a hybrid system with an MP regulator inside with a manifold and straight runs of low pressure to each fixture or there will be an MP regulator at each fixture of there is no manifold. And just because it's high pressure doesn't mean you'll have enough gas, you need to size it up with a riser diagram with the BTU of each fixture and see what size the meter is. More often than not they will need the gas company to install a larger meter to accommodate the higher CF/HR of demand on the system. 

Stay away from that manometer I actually bought it after mine crapped out and it's a piece. It went in the garbage. I got a dual port field piece from the supply house that was about 125$ and it's very nice and accurate.


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## UN1TED-WE-PLUMB (Oct 3, 2012)

Dual is nice because you can check inlet pressure and manifold pressure at the same time and it will show the difference in pressure from one side to the other.


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## Maximumplumbing (Nov 6, 2010)

Well I couldn't find any info on the meters themselves. I've got a call in to the gas supplier. The meters are large, the building is huge, the gas lines probably run close to 1000 feet, and they only come in 1.5 from the meters. There are maybe five 300-500,000 btu hanging heaters running off these lines. I'd say they are right about high pressure but who knows how high. If I can test these things and figure out what I need without have to wait on someone who probably doesn't care that I'm waiting, I'd be thrilled. But I like quality equipment that I have to buy once. What brand was that manometer you got at the local supplier?


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## antiCon (Jun 15, 2012)

Regulators come in different pressure sizes probably a 2 pound reg .. Did u check the specs on the gen.?


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## antiCon (Jun 15, 2012)

Sry yes you need a manometer to check the pressure of water column or psi


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## Gettinit (May 9, 2012)

UN1TED-WE-PLUMB said:


> You can tell the gas pressure by looking at the system if you know what to look for. If its high pressure it probably means its 2psi. The regulator at the meter will have a yellow sticker that says 2 psi and it will either be a hybrid system with an MP regulator inside with a manifold and straight runs of low pressure to each fixture or there will be an MP regulator at each fixture of there is no manifold. And just because it's high pressure doesn't mean you'll have enough gas, you need to size it up with a riser diagram with the BTU of each fixture and see what size the meter is. More often than not they will need the gas company to install a larger meter to accommodate the higher CF/HR of demand on the system.
> 
> Stay away from that manometer I actually bought it after mine crapped out and it's a piece. It went in the garbage. I got a dual port field piece from the supply house that was about 125$ and it's very nice and accurate.


You didn't like your Dwyer? The biggest reason I bought my first one is because I needed it to be FM rated....everything did but it was the only tool purchase I can recall. I believe mine is a 000 Mark III.


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## Gettinit (May 9, 2012)

Colors are regional or Gas supplier specific. If you don't know your colors call your gas company. We have red for 2#, blue for 5#, and it used to be green for 10# ( it may have changed in the past few years, they are uncommon.).


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## Gettinit (May 9, 2012)

RW Plumbing said:


> Now what's the story on the dual vs single. What can the dual do the single can't?


Another nice feature of many dual monometers is the ability to read negative pressures. Handy with pressure switches and other stuff. You can also read differential pressures like pressure drops after coils.


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## RW Plumbing (Aug 16, 2010)

So it's worth it to go dual right away then. Okay I will probably get that one the .


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## UN1TED-WE-PLUMB (Oct 3, 2012)

Gettinit said:


> You didn't like your Dwyer? The biggest reason I bought my first one is because I needed it to be FM rated....everything did but it was the only tool purchase I can recall. I believe mine is a 000 Mark III.


I'm sorry I didn't click the link until just now... That is not the meter I purchased from amazon, my mistake. The meter I have now is Field Piece dual port.


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## UN1TED-WE-PLUMB (Oct 3, 2012)

I was under the impression this was a residential application. It may be a 5 or 10 psi system. Still the regulators should be marked. If no regulators at all then it's probably a low pressure system. Also read the meter, what CFH is it rated for. It needs to be sized properly.

The regulators will be marked with metal tags, it is required by code that they are. It's in my code book. 

The regulators will tell the story read the regulators (or lack therof) for your answers as to what type of system your dealing with.


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## Gettinit (May 9, 2012)

UN1TED-WE-PLUMB said:


> I'm sorry I didn't click the link until just now... That is not the meter I purchased from amazon, my mistake. The meter I have now is Field Piece dual port.


The links are UEI and they are good manometers. I have friends that like theirs. I had a dual port FP, but like having a standalone unit so I am not relying on my meter and the fact that I can multitask.


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## UN1TED-WE-PLUMB (Oct 3, 2012)

Gettinit said:


> Another nice feature of many dual monometers is the ability to read negative pressures. Handy with pressure switches and other stuff. You can also read differential pressures like pressure drops after coils.


Can you explain why some gas valves have negative gas pressure? That means its drawing a vacuum right? I can't seem to figure this out.. Maybe it's just the way some valves read pressure ?


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## Gettinit (May 9, 2012)

UN1TED-WE-PLUMB said:


> Can you explain why some gas valves have negative gas pressure? That means its drawing a vacuum right? I can't seem to figure this out.. Maybe it's just the way some valves read pressure ?


What I was referring to were for drafting mainly. As far as gas valves go, I personally have never seen a gas valve read negative but have seen diaphrams "sucked out" by being undersized with generators. Trane burners on package units pull gas in so they would need to be checked with the negative side.

Nit sure if I answered your question?


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## UN1TED-WE-PLUMB (Oct 3, 2012)

Well in particular when I tune an Eternal water heater, it needs to read between 0 and neg .06inwc. I thought that was kind of an odd pressure to run at.


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## Maximumplumbing (Nov 6, 2010)

Holy crap, I just looked at some pics I took of the meters. The tags are in rough shape but I can make out 25 psi. The cfu, I can't make out. I'll have to go back out to look in person for that. One tag is blue with and another meter has a red tag that says temperature compensated meter.


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## Tim`s Plumbing (Jan 17, 2012)

I know the original post was talking about a commerical building but it still amazes me when I hear some of you guys talking about high pressure gas in a home.

Here in Mass we have to have plans drawn up by a registered engineer then sent to the state plumbing a gas board for approval. And the will only allow it in a commerical building. Then painted yellow with markings every 10` stating high pressure natural gas with the pressure.


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## Gettinit (May 9, 2012)

UN1TED-WE-PLUMB said:


> Well in particular when I tune an Eternal water heater, it needs to read between 0 and neg .06inwc. I thought that was kind of an odd pressure to run at.


I have never installed one so I cannot comment on them, sorry. If I did I would be talking out of my a$$. It isn't common but it is what it is. Is that the manifold pressure at low fire or high fire?


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## Gettinit (May 9, 2012)

Tim`s Plumbing said:


> I know the original post was talking about a commerical building but it still amazes me when I hear some of you guys talking about high pressure gas in a home.
> 
> Here in Mass we have to have plans drawn up by a registered engineer then sent to the state plumbing a gas board for approval. And the will only allow it in a commerical building. Then painted yellow with markings every 10` stating high pressure natural gas with the pressure.


I don't know what "high pressure" means to others. It is common to have 2# going in a home. I do think its a little odd when they use an old likely oversized 1/4# system and make it a 2# system just to add an appliance.

10# here is usually run directly from a meter to a boiler in a boiler room through one wall. I would have to check but I don't think your allowed to run it any other way as far as code goes. I am sure there are exceptions.


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## Tim`s Plumbing (Jan 17, 2012)

Here in Mass anything over .5 lbs is high pressure gas.


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## UN1TED-WE-PLUMB (Oct 3, 2012)

Gettinit said:


> I have never installed one so I cannot comment on them, sorry. If I did I would be talking out of my a$$. It isn't common but it is what it is. Is that the manifold pressure at low fire or high fire?



Manifold pressure at every level of modulation.


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## redbeardplumber (Dec 4, 2012)

Great thread boys, I think I need a digital manometer.... I was checking the pull off a power vent HWT. And I couldn't with my old style. Tank you tank you.


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## Gettinit (May 9, 2012)

redbeardplumber said:


> Great thread boys, I think I need a digital manometer.... I was checking the pull off a power vent HWT. And I couldn't with my old style. Tank you tank you.


Relcome.


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## pilot light (Apr 21, 2012)

Maximumplumbing said:


> I'm looking at a gas job, it's to install a supply for a generator. I'm wondering what you guys use as some type of gauge to check the existing pressure of the existing gas line. I'm told its high pressure and that its plenty to supply the generator, but I'd like to test it myself so I can determine the right regulator to use. Any ideas on an accurate and quality gauge for this, and to also double check for leaks prior to firing things up. What do you guys use?


What stage are you talking about for propane or is it natural gas? What is high pressure? Please elaborate on your question further! I would use a gauge that would not overload or spike the gauge I was using ! As far as supply is concerned you might want to check the pipe sizing and the math too beforehand! I like a rich soap and water blend too check for leaks!


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## justme (Jul 4, 2012)

Maximumplumbing said:


> Holy crap, I just looked at some pics I took of the meters. The tags are in rough shape but I can make out 25 psi. The cfu, I can't make out. I'll have to go back out to look in person for that. One tag is blue with and another meter has a red tag that says temperature compensated meter.


Some regulators work with lets say 5 psi to 25 psi and drop the out going pressure to ounces . You need to get a gauge to determine what pressure you are working with. Don't be the guy who trusted a sticker on a regulator and caused a flash fire because he didn't have the proper regulator.:no:


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## pilot light (Apr 21, 2012)

You should also check combustion with an combustion analyser!:yes:


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## antiCon (Jun 15, 2012)

This is what I use 











Mostly I use it to adjust manifold pressures on tankless it has a max testing range up to 14 psi reads both - and + pressure


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## Maximumplumbing (Nov 6, 2010)

justme said:


> Some regulators work with lets say 5 psi to 25 psi and drop the out going pressure to ounces . You need to get a gauge to determine what pressure you are working with. Don't be the guy who trusted a sticker on a regulator and caused a flash fire because he didn't have the proper regulator.:no:



This is a natural gas system by the way. I understand the regulator thing. I'm talking about the meter outside says 25 psi. What type of gauge was my question, to determine what regulator I needed.


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## TX MECH PLUMBER (May 27, 2011)

You need to just put a grade a gauge on it if it is that hi of oressure and see what the psi is. Then you need to know your psi/wc pressure needed for your line coming out of the regulator. Then get a reg made for those inlet and outlet pressures. The outlet pressure will have a range say 9 in w.c. To 20in w.c. And will be set in that range. Then you need a w.c. Gauge or Mano meter to hook up on the regulator and adjust it to the desired pressure Think of the regulator a water pressure regulator. You would set it the same way !! What are you feeding with this gas???


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## UN1TED-WE-PLUMB (Oct 3, 2012)

Get a regulator made?? I've never heard of this before.


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## plbgbiz (Aug 27, 2010)

UN1TED-WE-PLUMB said:


> Get a regulator made?? I've never heard of this before.


When I order regulators, I specify the BTU's, input pressure, and output pressure. They "make" or more correctly...install the proper orifice and spring to meet the specs.


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## UN1TED-WE-PLUMB (Oct 3, 2012)

That's cool.. I'm sure that's not for residential is it?

Who makes regulators? Do you just order through the supply house?


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## plbgbiz (Aug 27, 2010)

UN1TED-WE-PLUMB said:


> That's cool.. I'm sure that's not for residential is it?
> 
> Who makes regulators? Do you just order through the supply house?


From the supplier. Depending on the specs, they choose the manufacturer.

It is usually for commercial applications. The resi stuff is on the shelf everywhere.

The most recent one a couple of weeks ago was setup for 1-1/4" ip, 840Kbtu, 2psi input pressure, 14wc output pressure, internal bypass for indoor use with no vent. They had all the bodies, springs, and orifices in stock. They had it on the counter 30 minutes after I called it in.


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## UN1TED-WE-PLUMB (Oct 3, 2012)

That's some mega BTU's. 

When you say supplier you mean like fergusons? Or a special gas supplier?


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## plbgbiz (Aug 27, 2010)

UN1TED-WE-PLUMB said:


> That's some mega BTU's.
> 
> When you say supplier you mean like fergusons? Or a special gas supplier?


Federal Corporation. Just about everything that is special order for everyone else is stock for them. Controls, steam, gas, big stuff.

This regulator was for a paint booth dryer for an auto body shop.


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## justme (Jul 4, 2012)

Yea there's a few places here in the D/FW who change the springs and orifices out to what you need on the spot . Oslin Nation is the one in town I always go to.


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## justme (Jul 4, 2012)

Maximumplumbing said:


> This is a natural gas system by the way. I understand the regulator thing. I'm talking about the meter outside says 25 psi. What type of gauge was my question, to determine what regulator I needed.


Any regular spring gauge will give you the answer you need. Your talking about a service regulator like this http://sensus.com/documents/10157/34340/DS-G-REG-1361(243).pdf . You need to just get a gauge and get on the roof shut the gas off to one of the regulators on the roof ,remove it and install a 50# spring gauge . If that gauge shows around 2 -5 psi put a 15# diaphragm gauge on there and get a exact pressure reading. Then you will know what regulator you will need , then just size it out per the BTU rating on the equipment per the charts and you will be good to go.


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## TX MECH PLUMBER (May 27, 2011)

That's what I said but you say it better!! Lol


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## plumbing ninja (Jan 15, 2012)

You could use Old Skool (Glass Tube) or New Skool (Electronic) manometers , A Compound Vacuum Gauge & 3 vlv manifold arrangment. Leak Detector & Regulator go buy from Swagelok Dealer. Swagelok Snoop is a fantastic leak detector a bit more professional that soapy water! The Swagelok regs are used on LNG and compressor stations thru out the world. Gauges are "Wika" rebranded Swagelok. Other good gauge brands are Dwyer, Baumer, Ashcroft too name a few


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