How to Calculate Gas Load | Plumbing 101

[@taa347]

I'm going for my plumbing inspector's license and this is really one of the only things I just never got a chance to learn so thank you so so much for making this video.

[@Lonzohiggins999]

After many educational videos to use as context I finally feel like I fluently know the steps from start to finish to do this since you basically summarized it quick and easy here. To those who don't get it the first time looking into the code books chart might get some dots to connect

[@pandoxity9181]

I'm 18 and trying to get into a plumbing apprentice and been watching your vids for tips and to jumpstart my knowledge so thanks for the vids!!!! great explanations

[@RogerWakefield]

That is awesome! I love hearing that, good luck to you!

[@jenko701]

The DR phill of plumbing. Great channel.

[@mobilecommunicationsnetwor5268]

Will the meter need to be changed for your tankless example ? What is the residential output side of the gas meter? Normal installation size?

[@robertsarhanmd6433]

Excellent Professor, Thank You, Robert

[@boby115]

You will want to add 3 or 4 feet for everyone of your fittings. Roger’s understanding is correct but his explanation is somewhat confusing. Been in the gas industry for over 35 years , rather than me explain the correct way on sizing gas pipe, I invite you to go to Gray Furnace Man on KZbin (gas line sizing video), there’s no better man to explain gas line sizing & appliance line drops on KZbin . After watching his video on line sizing, let me know what you all think👍 (I can assure you, no one should have any arguments after watching).

[@kenbrown2808]

and this is why smart gasfitters in my area have started running a dedicated line to the water heater, if it's not the first point in the run. then they can run it at a higher pressure if they need to, to accommodate a tankless.

[@333mikeray]

As an inspector I've had numerous big builders try to over ride my fail for incorrect gas line sizing in new homes. Their defense is saying "It will work ok". Or "It was only size CSST that Home Depot had in stock". Even worse, the County has allowed them to succeed and forced me to pass inspections. I was holding up the projects they claimed.

[@st3vohhhh]

Great refresher!

[@jacobkindsvatter4055]

I enjoy running gas pipe threading is the cheapest and most reliable way to do it but i would like to hear some thoughts on other brands like trac pipe, ward flex, and mega press, i have done all of the above and still threading is still my favorite way to do it

[@Allintn22]

I agree

[@terry6665]

Roger, what's our go to gas bible in TX? Maybe you can do a video on reference material for this. Thxs!

[@Richard.Sanchez]

How do you find the inlet pressure pressure drop and specific gravity?

[@ron4274]

4:38 After correcting the small math error (257+160=417), the 1.25" pipe would need to be extended back another branch in the video example. (Easy for me to say, I'm not trying to write backwards and do math at the same time.) Worth mentioning too that fittings add more "equivalent length" than straight pipe and can sometimes bump the results up a pipe size. Unfortunately, physical installations are rarely as straight forward as paper plans (lol).

[@lyricstogo1463]

What's the the recommended plumbing materials to study for improvement?

[@williammontgomery2942]

Great video Roger!! Quick question; is there a way to measure the BTU from the end of a branch? I want to replace a 150K BTU firepit burner with a 240K burner. Is there a way to determine if enough gas is available to go to 240K or will I need to use your video and get my ruler and calculator out!! Cheers!!

[@wintonhudelson2252]

Add the lineal feet each ell or branch of a tee to the O.A.L. piping structure. Rinna tankless at 199,000 BTU are sensitive to gas pressure drops and water pressure drops. Main symptoms are won't come up on high fire.

[@johngraziano6652]

Looking for some advice doing lot of research and asking questions, im not sure if my gas meter and pipe set up is ok to run a tri fuel generator and or some of my gas appliances, mostly my NG furnace . some say its ok, some disagree. MY GAS METER INFO .5-7 WC , (1.2-1.7 kPa W.C.) and 1000 BTU a cubic foot . so my regulator reads 'B42R ORI 1/8 5-7 IWC 125 PSIG MAX 8/08 The meter says AC-250 250 C.F.H @ 1/2 DIFF. MAOP 5PSI. my gas furnace furnace draws 120k, water heater draws 40k, I have a gas drier and stove, but during an emergency, wont be using them,, A Trifuel Generator I was looking at is CHAMPION TRI FUEL GENERATOR REQUIREMENTS Nominal fuel rating- 1000btu a cubic foot. Fuel supply size-1/2inchFNPT. Fuel supply pressure 5-7wc. Max flow rate 135000 btu MY NG LINE LAYOUT I have a 3/4 pipe going from the main 1in to the back of the house,straight line directly opposite the meter aprox 25 ft. When the 3/4 in pipe exits the house, I have a shutoff valve and a 1/2 reducer so as to attach a 1/2 flex hose to the generator. ( Off the 1 inch main are the branches for the furnace ,drier water heater and stove and now the generator line) Thanks for any advice you can give John

[@HWLPOutdoors]

Great video!

[@DJSephEntertainment]

So when you get to the water heater you reduce to 3/4 which the tankless accepts?

[@johntruitt5899]

Hey roger do you still have your plumbers cut and thread all of the gas piping you install? Or do you use csst (corrugated stainless steel tubing)?

[@condor5635]

My generac installer and plumbing inspector both said I am good with my existing meter. Meter is 240 cfh. I have a gas furnace -100,000 BTU, gas dryer - 25,000 BTU and a gas water heater ~40,000 BTUs. The generac at full load is about 225,000 BTUs. I say they are wrong and I will probably have issues just running furnace and generator alone. Help!

[@ChefBoyareB]

I learned that 257 + 160 = 317 today.

[@ricksanchez6411]

I thought I was the only one who saw that

[@markmonaco8901]

Thank you very much

[@RogerWakefield]

Any time

[@lactobacillusprime]

writing in mirror alphabet real time is quite a little trick you're seem to be doing here! :)

[@mattmas8640]

Question for you. I have 70’ for my furthest distance. However, I want to install a 199,000 tankless water heater. The tankless water heater only has 3/4” connections. Using the chart, 3/4 is not supposed to be utilized even in a branch off of a 1-1/4 just to supply the water heater. The chart would state that I would need a 1” connection to the water heater. How do you get around this to meet code? Do you just reduce down to 3/4” close to the water heater?

[@ron4274]

Correct, just reduce down to 3/4" pipe near the TWH. If you refer to the sizing table in the video, 3/4" schedule 40 metallic pipe will support a BTU load of 247 cu. ft./h (assuming the same conditions) for an "equivalent length" of 20' (Note: The length of fittings is calculated differently than straight pipe - search online for a table that provides the equivalent length of fittings when sizing gas piping).

[@larrytheplumber9851]

Good shyt

[@leonardoaguilar1357]

Thank you 🙏🏻 very much 👌🏻👌🏻👌🏻👌🏻👍🏻👍🏻👍🏻

[@RogerWakefield]

Most welcome 😊

[@yermoffroad]

Is pressure drop what the overall pressure will drop to when everyhing is running or how much it will drop from the original supply pressure?

[@SpartanIV]

I'm not a plumber but I believe the pressure drop of the table is the acceptable pressure drop with everything utilized. If you look at tables with higher pressure drops the BTUs that can be supplied by any pipe diameter goes up. That's because you're gaining more capacity at the sacrifice of pressure. What is an acceptable pressure depends on the pressure your gas regulator is providing and what your appliances specify as the minimum.

[@perrypstokes9868]

1/2 to 1 pound system with 3 appliances anything over 20 feet of run if u can tie it right outside ur always good

[@danielwilson9049]

So if the water heater is the first thing on the line after the meter, do i still measure all the way to the furthest point or just to the water heater?

[@pq9254]

Of course

[@ThoraxThePlumber]

Would it make a difference in your calculations between natural and propane?

[@nicholastrentini1999]

How hard is it when it comes to measurements and plumbing

[@matthewwright1813]

Mr. Wakefield, could you do a video on Water Column for the same system here?

[@andrewwelch5668]

What do you mean by "Water Column"?

[@matthewwright1813]

Water column is an alternative way of expressing measurements of pressure. This measurement is defined as the pressure produced by a 1-inch by 1-inch column of water with a specified height.

[@paralellosll3849]

Oh my god... I finally found someone who does math like me 🤯

[@ShrimpCracka]

so this applies for a meter thats 7wc? or a meter that is 2psi?

[@Tommyhawk068]

MTR would have to be pushing 2LBs if he’s basing his calculations off 2LBs.

[@joeheiliger3956]

How does this differ when using regulators?

[@Pipelinernick]

One thing not covered here is can the meter pass the proper amount of gas for the application. In this case you'd need atleast a 425 cfh meter

[@Helpfulsuggestions]

I’m confused as all this still apply if it’s a five psi system ??

[@nathancastro7942]

How do you know what the meter out is?

[@andrewwelch5668]

I know these videos are intended for the purpose of giving pointers and advice to plumbers and gas fitters as well as for those striving to be plumbers and gas fitters. You have to figure that some DIYers are looking at this stuff too and thinking that they can do it as well...without the proper training and licensure. Only takes 1 moron to THINK they can do this before they make a dangerous situation for themselves and their neighbors messing with gas piping. DO NOT TRY THIS IF YOU DON'T KNOW WHAT YOU'RE DOING!!!

[@kenbrown2808]

remember: a water leak can make your house fall down. a gas leak can make your house fall up.

[@nortonplumbing9552]

This is the biggest thing I have to explain to my customers. Then with the electric tankless option, it is kind of the same...do you have enough power to run this thing? It is never a clean swap.

[@billcryer3389]

Sizing gas pipe is simple.

[@13072b]

What happens if meter is 250 or less .

[@ricksanchez6411]

Gas company will up size

[@billcryer3389]

Sizing has is simple

[@thewaterheaterfactory]

Is there an expansion tank for gas lines? To expand the volume? Oh wait did I just invent that? Great video thanks!

[@dr.roostertail9274]

You casually say that you need the proper chart for your area to determine pressure drop. I cant find info anywhere! How do you find the local information?

[@mondavou9408]

I learned its hard to write backwards

[@RogerWakefield]

it is quite tough lol

[@Seven7Pain1]

or save your brain and like Rinnae water heaters taught me tankless outside heaters place them right beside the meter and 90 percent of time that will work

[@Lessergoblin]

can I hack it to save money tho? I switched heater, range and hot water heater to gas.

[@jameschuke4104]

Fu k it iam lost

[@jwblount7802]

Or you could just install the tankless that is designed to replace a tank heater which will supply the same amount of hot water as tankless water heater that you explaining without adding the cost of changing the old gas line. Just saying....

[@fixerupperer]

What? Tankless use more gas over a short period of time vs tank style heaters. Go find a tankless that only runs at 35k-50k btu and see what the temp rise and gpm are.

[@jwblount7802]

@@fixerupperer Rheem, States, and Navian to name a few that run on the existing gas line that is for replacing an existing tank water heater for a whole house set up, Especially for the size house he was describing in this video. So look around and ask they're out there and I have installed them and they work pretty well.

[@pleasureincontempt3645]

Haha, your backwards C is not impressive. Clarity over style is more important.