Gas Water Heater Installation - Flex Line vs Rigid Pipes

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Bucky Plumber

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Hello,

I am preparing to replace my 12 year old 40 gallon gas water heater.

Currently my water heater is installed with rigid copper water lines and gas pipe, see picture below.

I am wondering if there is a preference or code regulations for using rigid pipe versus flexible lines (I am located in Wisconsin). Also if there are any advantages/disadvantages to each method, like water flow restriction with the braided water hoses?

My thought currently is to use copper pipes for water lines but change the gas supply to flexible line.

Thanks in advance for your advice!

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Geofd

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I would pipe in rigid copper and rigid steel do ridiculous copper on the releif valve also if you don’t have the means to thread the steel pipe Home Depot will cut measures for you
 

Geofd

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I would pipe in rigid copper and rigid steel do ridiculous copper on the releif valve also if you don’t have the means to thread the steel pipe Home Depot will cut measures for you
Disregard the word ridiculous this computer auto corrects
 

Mitchell-DIY-Guy

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Personally I'd use flex lines both for gas and for water; the reasoning is quite simple. When replacing tanks--and I've done severeral, I've never come across the gas entry, and the water connections is exactly the same place. To make your next installation easier and this one, just use flex lines.

I even had to install a flexible connection on the power vent which had previously been rigid, but the new water heater had the power vent exhaust in a different location.

Do yourself a favor, too: invest the whopping $5 in another valve and add one to the hot water side of the tank too. This way you can totally isolate the house water system from the tank without having to drain the house lines. Next time you change the tank, the installation will be even easier.
 

breplum

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Flex. Always. And add a valve on the hot side too, while you are at it. Makes changing out later so much easier.
I would install a code required Watts 210 valve according to instructions.
I have no idea why they went up into the stratosphere on price.
Really, with carpeting, you are just asking for a tank failure
 

Riickk

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You may not need to change gas line at all.
Last time I swapped water heaters, height of gas line was identical, old and new.
Just break open the union, unscrew the gas line from old WH, and if height is the same,
install old line to new WH. Then, draw the water lines.
A. Iron pipe is a lot less delicate than flex gas pipe.
B. If it ain't broke, don't fix it.
............. JMHO

edit: In addition, if new WH is same overall height, you may not even need to play with the vent pipe.
But I don't know if you've already bought the new unit.
 
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Rossando

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You guys catch everything, well there is a drip leg already but it should be closer to the fixture it serves.

As for the tank being elevated here it’s not code to have a stand but if there is one we can leave it or drop it on the floor. What it’s supposed to do is prevent the water heater from getting damaged in cases of flooding etc.
I can’t tell you guys enough how much better it is to have flex lines to make servicing go a lot smoother. If the inspector doesn’t say anything about it do as you please.
 

Dan the Plumber

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Flex. Always. And add a valve on the hot side too, while you are at it. Makes changing out later so much easier.
I would install a code required Watts 210 valve according to instructions.
I have no idea why they went up into the stratosphere on price.
Really, with carpeting, you are just asking for a tank failure
Definitely agree with Broplum. I live in earthquake country and a rigid gas pipe could have disastrous effects in a shaker. 'Course your house insurance will pay for fire but not for earthquake so ....
 

Mitchell-DIY-Guy

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Definitely agree with Broplum. I live in earthquake country and a rigid gas pipe could have disastrous effects in a shaker. 'Course your house insurance will pay for fire but not for earthquake so ....
I agree also...especially with the valve on the hot side. Breplum may be the only professional plumber who does that, since I've never seen it anywhere unless I put it in myself. I'm not a pro. Just one who understands I may the the next person working on it!
 

skeezix

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Before you buy, measure the proposed tank carefully. Measure its diameter as well as its height. I just replaced my heater with an A.O. Smith, and the new heater's diameter was 2 inches larger than the old heater. That meant I had to position it slightly different from the old heater and when I did so, the copper inlet and outlet pipe connections on the heater were out of whack from the exterior copper plumbing.

The copper piping was installed in 1982 and some of the fittings were difficult to remove. I should have just installed flex lines but being a glutton for punishment, I broke out the bernzomatic torch...

And... the center line of the new heater (and consequently the location of the flue) was also offset from the old center line and so I had to monkey around with the flue and exit pipe.
 

House Doc

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The reasoning behind raising the heater 18" off the floor of a garage is that gas fumes can crawl across the floor and be ignited by the pilot light of the heater, not because of flooding. If you've got 18" of water in your garage probably the water heater is the least of your worries. :eek:
 

Riickk

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I live in earthquake country and a rigid gas pipe could have disastrous effects in a shaker. 'Course your house insurance will pay for fire but not for earthquake so ....
You notice that both of those HW tanks are strapped to the wall behind them.
 

frodo

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You guys catch everything, well there is a drip leg already but it should be closer to the fixture it serves.

As for the tank being elevated here it’s not code to have a stand but if there is one we can leave it or drop it on the floor. What it’s supposed to do is prevent the water heater from getting damaged in cases of flooding etc.
I can’t tell you guys enough how much better it is to have flex lines to make servicing go a lot smoother. If the inspector doesn’t say anything about it do as you please.



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wh_platform.pngwh_platform.png
 

brians356

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The tank should be plumb as well. Is 1.5 degrees out of plumb worth worrying about?
 

skeezix

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Mine is about a degree out-of-plumb. Has been for 25 years. Haven't noticed any problems.
 
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