# A couple of my gas water heater installs.



## service guy

Nothing special, just a couple water heater replacements.

This is the one that I installed in place of a "aquastar" tankless. The homeowner was tired of crappy performance, and wanted HOT WATER AT MULTIPLE FIXTURES AT ONCE! The tankless salesman lost this one...couldn;t promise the same hot water volume.








This is one I replaced today...


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## Titan Plumbing

What? You don't use unions on the water lines?


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## Master Mark

*noy too bad*

they dont look too bad...

the debate will rage over wether unions or female adaptors 
work best...

I like to support those thermal expansin tanks better with a leg....


the only thing I would suggest is you get into the habit of putting your name on your work so they remember to call you back someday.
furnace, heater and garbage disposal 

customers always forget who they called 2 years from now
but if you got your name plastered on your work it helps a whole lot.

this habit really begins to add up names over a year or two.....


also the Rheem heater will be there for a good 10 years, 
but the customer might be long gone ...
so the new people call whoever they see
on the heater.......


...


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## TheMaster

In the second pic the larger B-vent looks like its going down instead of going up. Also looks like the draft diverter is alittle crooked too.


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## RealLivePlumber

Not bad.

The flex gas supply would not pass inspection here, if it were not strapped to the WH. It is a little long, also.


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## Ron

I see no screws attached on the draft hood on the flue. That would fail inspection here, min or three screws are required.


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## service guy

Ron said:


> I see no screws attached on the draft hood on the flue. That would fail inspection here, min or three screws are required.


The screws are there. They are under the b-vent ring where it attaches to the flue. 3 stainless screws.:thumbsup:


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## service guy

TheMaster said:


> In the second pic the larger B-vent looks like its going down instead of going up. Also looks like the draft diverter is alittle crooked too.


That's because the flue is going the other way, :laughing:coming FROM the furnace and going uphill through the wall behind the heater. It is hard to tell from the pic. I am not much of a photographer.

It is slightly crooked, working with the original flue, I didn't change it, but I have it to screwed to the draft hood 3 places, so it will be fine


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## TheMaster

service guy said:


> That's because the flue is going the other way, :laughing:coming FROM the furnace and going uphill through the wall behind the heater. It is hard to tell from the pic. I am not much of a photographer.
> 
> It is slightly crooked, working with the original flue, I didn't change it, but I have it to screwed to the draft hood 3 places, so it will be fine


 Yeah I really dont agree with common venting appliances but I understand somtimes you must work with what you have.


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## pauliplumber

I never use unions, most don't in MA. Not sure exactly why, but you can't use gas flex connectors on water heaters here. Yet you can use SS flex pipe:blink:.


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## Ron

What type of pipe is that coming off the T&P?


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## pauliplumber

I was wondering the same thing. Looks like pex.


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## OldSchool

Ron said:


> What type of pipe is that coming off the T&P?


I think that pipe comes with the tank for the relief.... it does here anyway


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## Ron

OldSchool said:


> I think that pipe comes with the tank for the relief.... it does here anyway


I just wonder if there is any reduction in it?


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## Mike Jessome

is it I was taught wrong or do you have a potable expansion tank on the cold side I was taught to put them on the hotside... am I missing something here...


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## gusty60

Mike Jessome said:


> is it I was taught wrong or do you have a potable expansion tank on the cold side I was taught to put them on the hotside... am I missing something here...


Watts says put them on the cold side. So i put them on the cold side. Don't know what other manufacturers say. Yours may be different.


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## service guy

Mike Jessome said:


> is it I was taught wrong or do you have a potable expansion tank on the cold side I was taught to put them on the hotside... am I missing something here...


You were taught wrong.


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## Pipe Rat

Cold Side :yes:
Hot Side :no:


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## jc60618

Piperat said:


> Cold Side :yes:
> Hot Side :no:


I was at a job where the expansion tank was piped to the hot water (foreman's idea). After the superintendent saw it a big argument occurred and a couple of days later it was piped to the cold side. I have also seen an expansion tank piped in before the checkvalve.


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## service guy

A thermal expansion tank will still work perfectly fine on the hot side, but the hot water will wear out the diaphragm a lot faster than cold water will.


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## smellslike$tome

I don't think I will ever post any pictures of *ANY* of my work on this forum :laughing:.

Oh yeah, is the Promax pan drain going through the floor to somewhere else? If not, why bother with the pan or the drain (yes I know the code requires it but it also requires drain piping to the proper place)

Sorry S.G., I just couldn't help myself, now tell me I'm blind and it runs through the floor for 20 feet and then out the wall to the flower bed.


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## smellslike$tome

Oh yeah, just a curiosity, seems like most folks find a brand they like and stick with it. Why 1 A.O. Smith and 1 Rheem?


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## service guy

smellslike$tome said:


> I don't think I will ever post any pictures of *ANY* of my work on this forum :laughing:.
> 
> Oh yeah, is the Promax pan drain going through the floor to somewhere else? If not, why bother with the pan or the drain (yes I know the code requires it but it also requires drain piping to the proper place)
> 
> Sorry S.G., I just couldn't help myself, *now tell me I'm blind and it runs through the floor for 20 feet and then out the wall to the flower bed.*


CLOSE! It runs about 40 feet through the floor to the backyard! You are smart!


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## service guy

smellslike$tome said:


> Oh yeah, just a curiosity, seems like most folks find a brand they like and stick with it. Why 1 A.O. Smith and 1 Rheem?


My supplier switched to Rheem, the first install is from last summer.

I like Rheem better so far. Less issues.


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## gear junkie

Unions on a water heater are a waste of time. No water heater stand?


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## service guy

gear junkie said:


> Unions on a water heater are a waste of time. No water heater stand?


Neither one needs a stand, they are not in garages.


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## Master Mark

*they really beat you up here*

they will really beat you up if you post pics

I have seen dumb asses actually pu t them on stands in 
basements before...

.....

I personally think that the pans are very important but the 
*thermal expansion tanks are a waste of time * because no one
checks the pressure in them and eventually they get 
waterlogged and very heavy just hanging there ....

finding a decent way to support them is always on my
 mind when we install them.......


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## Airgap

Master Mark said:


> they will really beat you up if you post pics
> 
> I have seen dumb asses actually pu t them on stands in
> basements before...
> 
> .....
> 
> I personally think that the pans are very important but the
> *thermal expansion tanks are a waste of time *because no one
> checks the pressure in them and eventually they get
> waterlogged and very heavy just hanging there ....
> 
> finding a decent way to support them is always on my
> mind when we install them.......


They're not a waste of time to me...It makes me feel smart when I explain to the lil' old ladies why they need the pretty blue tank...:thumbup:


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## Titan Plumbing

service guy said:


> A thermal expansion tank will still work perfectly fine on the hot side, but the hot water will wear out the diaphragm a lot faster than cold water will.


So, you're telling me that only cold water will expand out of the heater into the expansion tank?????? 

This argument does not hold water.


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## service guy

Choctaw said:


> So, you're telling me that only cold water will expand out of the heater into the expansion tank??????
> 
> This argument does not hold water.


Are you saying it doesn't matter which side then?
I still think installing it on the hot side will wear it out faster than the installing it on the cold side. The tank manufacturers think so too.


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## Titan Plumbing

service guy said:


> Are you saying it doesn't matter which side then?


I'm saying that I don't really see the difference.

They like us to put them on the cold side, so I do.

The inspectors have never been able to give me a legitimate reason why.


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## service guy

Choctaw said:


> I'm saying that I don't really see the difference.
> 
> They like us to put them on the cold side, so I do.
> 
> The inspectors have never been able to give me a legitimate reason why.


You are right, they are actually allowed to be installed anywhere on the potable system as long as there isn't a valve between the water heater and the expansion tank, but the argument that they belong on the cold side is due to the increased wear from being exposed to higher temperatures.


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## Titan Plumbing

service guy said:


> You are right, they are actually allowed to be installed any where on the potable system as long as there isn't a valve between the water heater and the expansion tank, but the argument that they belong on the cold side is due to the increased wear from being exposed to higher temperatures.


Look at it this way, when the heater is up to temp. and the water expands, isn't it just as hot as it is on the hot side. If no cold water is being introduced, it will be just as hot on the h or c side, right?

^that was a mouth full..................

By the way, I'm not arguing my point, I'm just looking for something besides...."well this is what they want".

I really don't care. :jester:


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## Miguel

I see Choctaw's point the way you have them mounted, service guy.
Right on top of the tank like that they're going to be subjected to temps at least almost as hot as the hot side when they're doing their job.
Of course it's what the mfr wants so it's covered anyway.

If I was the HO in any of those places and I paid you to install them as pictured I'd probably pay you and thank you for not wasting time, effort and materials to locate the exp tanks in a "safer environment". Single wall venting on the WH's? Then I might complain a bit.


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## Tommy plumber

*FVIR compliance*

I don't know why state gov'ts are so lax in our trade.:furious: I remember reading in like 2003 that an ANSI standard was adopted that required all gas W/H installed to be FVIR compliant (Flammabe Vapor Ignition Resistance). Essentially the combustion chamber is sealed so that a child cannot spill gasoline around the pilot light and burn themself. FVIR W/H also have some other interesting safety features like LDO( lint, dirt &oil). This feature prevents lint, dirt and oil from clogging the fresh air intake ports. If you install a non-FVIR compliant W/H and someone gets injured, everyone ( the media, forensic investigators, lawyers, inspectors, etc.) will be hanging the blame on the poor plumber. And it is really the fault of the gov't which failed to make sure that all us plumbers KNOW all the new standards. My Florida code book states that if the gas W/H is FVIR then it dosn't need to be on a safety stand. I strongly disagree. All gas W/H should be on a stand. Also the drip leg on the gas piping looks a little short. Also pvc is not permitted by code for a pan drain line on a W/H. Water can potentially be near 180 degrees or hotter if the T&P valve were to discharge. Pvc is NOT rated for that temperature. This installation would've failed inspection in Palm Beach county Florida.


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## service guy

Who pissed in your wheaties? If it makes you feel any better, the first picture is from last summer, and since then I switched to Rheem and all my gas water heaters are now FVIR. I won't be installing a non-FVIR water heater ever again.:thumbsup:
I disagree with you about every heater being on a stand. But that is what this forum is all about, many different perspectives.


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## service guy

Oh and my water heaters PASS inspection with flying colors, and I'm proud of my work.
That is cool if you have higher standards. Higher standards are always a good thing is in this trade.:thumbsup:


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## TheMaster

Tommy plumber said:


> I don't know why state gov'ts are so lax in our trade.:furious: I remember reading in like 2003 that an ANSI standard was adopted that required all gas W/H installed to be FVIR compliant (Flammabe Vapor Ignition Resistance). Essentially the combustion chamber is sealed so that a child cannot spill gasoline around the pilot light and burn themself. FVIR W/H also have some other interesting safety features like LDO( lint, dirt &oil). This feature prevents lint, dirt and oil from clogging the fresh air intake ports. If you install a non-FVIR compliant W/H and someone gets injured, everyone ( the media, forensic investigators, lawyers, inspectors, etc.) will be hanging the blame on the poor plumber. And it is really the fault of the gov't which failed to make sure that all us plumbers KNOW all the new standards. My Florida code book states that if the gas W/H is FVIR then it dosn't need to be on a safety stand. I strongly disagree. All gas W/H should be on a stand. Also the drip leg on the gas piping looks a little short. Also pvc is not permitted by code for a pan drain line on a W/H. Water can potentially be near 180 degrees or hotter if the T&P valve were to discharge. Pvc is NOT rated for that temperature. This installation would've failed inspection in Palm Beach county Florida.


 The 18" rule helps alittle but let me give you a scenario where it could cause even more damage being 18" off the floor. Car in garage leaking gas.....garage is air tight almost. Car has 25 gal of gas in it and is leaking at a good rate. Regular type water heater sitting on the floor...sure it will blow up but it will blow sooner right???? The fumes should reach the lower installed heater first...igniting a smaller amount of vapor. Now take the same regular non fvir water heater and install it on a stand 18" off the garage floor....remember the car had 25 gal of gas in it......how much vapor will the one thats 18" off the floor ignite? Ever consider that? Both ARE going to ignite if given time and the one thats 18" off the floor is gonna have more fuel to ignite. Thats why 18" off the floor isn't good enough and fvir was invented. If you want to do both theres no rule against it.


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## TheMaster

A.O. smith lost a case here when their gas water heater blew up...dertermined cause......bad gas valve. The control did not shut the flow of gas off but the heater was not lit...filling the garage with natural gas. There had been problems with the water heater staying lit. he wakes up in the middle of the night and decides to lite the water heater so he would have hot water in the morning...(so is believed) and must not have smelled the gas......he ignited the natural gas that was in the garage when he tried to lite the water heater. It blew the garage door and him out into the street about 60' away. He was killed. It was not from gasoline but I thought I would share the story. I typed this from memory...I worked for one of the lawyers that sued A.O smith. The lawyer said his team handed a.o smith their ass's and sent them back where they came from.
Add> Here a link to the lawyers website,look around at how much money these guys recover....THEY dont play.:laughing:
http://www.cunninghambounds.com/news.html?detail=1&news=300


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## Tommy plumber

*W/H's on a stand.*

I disagree with the scenario that a W/H on a stand will cause more damage if it ignites. That's like saying that it matters if you light a stick of dynamite from a fuse on the end or if the fuse is in the middle. It doesn't matter to the guy holding the dynamite when it explodes.:whistling2:


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## Protech

See pics. You should have used a brass fitting with a flanged backseat. Since you used copper fittings on galvanized steel without a fully dielectric connection, you have just created a galvanic cell. And it's against our code. BTW, where is the pan on that heater?:jester:



Protech said:


> Code violation: *605.24.1 Copper or copper-alloy tubing to galvanized steel pipe.* Joints between copper or copper-alloy tubing and galvanized steel pipe shall be made with a brass fitting or dielectric fitting. The copper tubing shall be soldered to the fitting in an approved manner, and the fitting shall be screwed to the threaded pipe.


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## Protech

They are only dielectric if installed properly.



Tommy plumber said:


> Look carefully at the W/H those ARE di-electric fittings installed by Rheem in between copper female adapters and the tank.


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## service guy

Protech said:


> That's not a runaway thermostat. That's a short circuit and has nothing to do with plumbing at all.


Yeah that looks like a short-circuit electrical fire. Not a plumbing issue.

Where are your thermal expansion tanks Tommy? Where is the pan drain?


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## Protech

Well, to be fair, we don't know that his heater is installed on a closed system.




service guy said:


> Yeah that looks like a short-circuit electrical fire. Not a plumbing issue.
> 
> Where are your thermal expansion tanks Tommy? Where is the pan drain?


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## service guy

Protech said:


> Well, to be fair, we don't know that his heater is installed on a closed system.


That looks like a large commercial heater to me. In that case, there should be a double-check in that potable system. I just got to the point that I install them on every heater. Occasionally I'll skip it, if they are on a well with a storage tank very close by with no checks between the two tanks.


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## Protech

That's a good point about it being commercial. I didn't catch that.



service guy said:


> That looks like a large commercial heater to me. In that case, there should be a double-check in that potable system. I just got to the point that I install them on every heater. Occasionally I'll skip it, if they are on a well with a storage tank very close by with no checks between the two tanks.


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## Protech

Here is the right way to connect to the heater. Notice the brass fittings to soften the difference in electronegativity between metals.


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## Protech

Another


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## Protech

Finished install


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## service guy

Nice looking work!:thumbsup:
Where are your expansion tanks/valves? Open systems in florida? No checks on your water meters?


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## SlickRick

Why is the valve on the hw side of the wh on Tommy's wh?


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## gusty60

slickrick said:


> Why is the valve on the hw side of the wh on Tommy's wh?


 Cuz there isn't one on the cold.:laughing:


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## Redwood

Tommy plumber said:


> here is a W/H that a real plumber installed. How do you like me now?:thumbup: Actually I don't know who installed this all I know is in addition to getting paid the owner tipped me $100 to replace it. What was someone saying about a runawat t-stat not happening. Just because YOU haven't seen it doesn't mean it dos not occur.


Looks to me like a water heater that was leaking and the electrical components got tired of working under water.

Notice the rust along the bottom of the upper cover and the rust stained drip lines running down from there?:whistling2:

Your diagnostic skills are amazing...:laughing:


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## gear junkie

Both Tommy and Protech are lacking soldering skills.


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## service guy

That ballvalve between the water heater and txt is a code violation. If someone closes it, the txt is useless.


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## service guy

What are those deadend female adapters for?


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## gear junkie

service guy said:


> That ballvalve between the water heater and txt is a code violation. If someone closes it, the txt is useless.


Agree 100% but I had to build to prints on this one. Never would do this otherwise. The dead ends with the fpt adapters are for thermal wells.


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## Protech

That was an open system(no checks or back flow preventers of any kind) and it already had a relief valve on the mainline. There is also a relief valve on the solar loop piping on the roof. No pan as it's in a dropped garage and the water will just run out the garage door if it leaks.



service guy said:


> Nice looking work!:thumbsup:
> Where are your expansion tanks/valves? Open systems in florida? No checks on your water meters?


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## Protech

What's wrong with my solder joints? :huh:

And since we are nit picking, you could have just used a thrd x thrd x swt tee in place of the 90 that drops into the cold side of the heater and set the tank right on top of said tee. That would have saved a fitting. I do have to give you props for using some brass nipples to keep the copper off of the steel tank though :thumbsup:.



gear junkie said:


> Both Tommy and Protech are lacking soldering skills.


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## gear junkie

Protech said:


> What's wrong with my solder joints? :huh:


Nothing too much, I just like to throw a curve ball at you now and then and watch the big words come across the screen. If I had to get to the nitty gritty, I would suggest wiping your joints with a dry rag to get rid of the excess solder.

Tommy's soldering ability however.....


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## ChrisConnor

Protech said:


> What's wrong with my solder joints? :huh:
> .


As long as you wiped the flux off and they ain't leaking, then they're good.

but you might want to start insulating your pipes, for cosmetic reasons.:whistling2:

Just kidding, who cares?


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## SummPlumb

I think it looks awesome man!


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## Protech

Flux is wiped and it's water soluble so it flushes away on the inside to when the water rushes thru. The pipes were insulated (for thermal reasons). What specifically looks so bad about them? 



ChrisConnor said:


> As long as you wiped the flux off and they ain't leaking, then they're good.
> 
> but you might want to start insulating your pipes, for cosmetic reasons.:whistling2:
> 
> Just kidding, who cares?


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## Roy

Just wondering the expanison tank goes on the hot water side. 
Look at the color code red is for hot water supply, blue for the cold side.
We only install hot water expansion tank units in a commerical bldg application.
Just wondering.


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## Plumbworker

those wells seem too far off to give a accurate reading. the well should be in the line of flow


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## SummPlumb

Roy said:


> Just wondering the expanison tank goes on the hot water side.
> Look at the color code red is for hot water supply, blue for the cold side.
> We only install hot water expansion tank units in a commerical bldg application.
> Just wondering.


 We install expansion tanks on any system that has a PRV. When you use a PRV it creates a "closed" system not allowing water to flow back and forth from the city to the house thru the water meter. On a closed system the hot water has no place to expand to. (City water)

I have tried the expansion tank both ways. I have found by personal experience that it works correctly on the cold side. 

We don't put any heaters on stands now. All gas heaters here (GA) are the new enclosed style burner heaters. Our pans are PVC. The lines out of them are PVC. Pans are only needed if the heater is on the second floor over a finished space or in an attic. I know PVC is not rated for hot water, but that applies to lines under pressure. It is a drain line, so I think it is ok. 
The pan is a joke anyway IMO. If you think about it, most traps under sinks are PVC including your washing machine drain. Heck, most three compartment sink drains here are PVC. 

It is interesting to see how other people do it in other states....


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## Plumber Jim

SummPlumb said:


> We install expansion tanks on any system that has a PRV. When you use a PRV it creates a "closed" system not allowing water to flow back and forth from the city to the house thru the water meter. On a closed system the hot water has no place to expand to. (City water)
> 
> I have tried the expansion tank both ways. I have found by personal experience that it works correctly on the cold side.
> 
> We don't put any heaters on stands now. All gas heaters here (GA) are the new enclosed style burner heaters. Our pans are PVC. The lines out of them are PVC. Pans are only needed if the heater is on the second floor over a finished space or in an attic. I know PVC is not rated for hot water, but that applies to lines under pressure. It is a drain line, so I think it is ok.
> The pan is a joke anyway IMO. If you think about it, most traps under sinks are PVC including your washing machine drain. Heck, most three compartment sink drains here are PVC.
> 
> It is interesting to see how other people do it in other states....


We only install expansion tanks if it IS a closed system. some PRVs have a thermal bypass and as long as the outside pressure isn't at 150 psi or more the expansion will go out the bypass. as for pans do you use the plastic pans for gas heaters? we use the metal pans. I have used the pvc on the drans for the pans though and pipe the t&p seperate from the pan.


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## SummPlumb

Plumber Jim said:


> We only install expansion tanks if it IS a closed system. some PRVs have a thermal bypass and as long as the outside pressure isn't at 150 psi or more the expansion will go out the bypass. as for pans do you use the plastic pans for gas heaters? we use the metal pans. I have used the pvc on the drans for the pans though and pipe the t&p seperate from the pan.


 Good question....I have never put a gas WH in a pan. If I did, I would prob use a metal one. We cannot put relief lines into pans here. They make us pipe them all out here. Most of the time, the gas WH is beside of a furnace in a basement inside of a mechanical room. Then I can use the floor drain for the relief line. 

Our pressure here in some places touches 160. I use a Watts brand PRV. (25AUB)? I think that is the right number. Besides, we both know if the heater bust, the pan is nothing but in the way.


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## GREENPLUM

SummPlumb said:


> We install expansion tanks on any system that has a PRV. When you use a PRV it creates a "closed" system not allowing water to flow back and forth from the city to the house thru the water meter. On a closed system the hot water has no place to expand to. (City water)
> 
> I have tried the expansion tank both ways. I have found by personal experience that it works correctly on the cold side.
> 
> We don't put any heaters on stands now. All gas heaters here (GA) are the new enclosed style burner heaters. Our pans are PVC. The lines out of them are PVC. Pans are only needed if the heater is on the second floor over a finished space or in an attic. I know PVC is not rated for hot water, but that applies to lines under pressure. It is a drain line, so I think it is ok.
> The pan is a joke anyway IMO. If you think about it, most traps under sinks are PVC including your washing machine drain. Heck, most three compartment sink drains here are PVC.
> 
> It is interesting to see how other people do it in other states....


 
most of the places i work have a check valve right after the meter


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## TheMaster

SummPlumb said:


> Good question....I have never put a gas WH in a pan. If I did, I would prob use a metal one. We cannot put relief lines into pans here. They make us pipe them all out here. Most of the time, the gas WH is beside of a furnace in a basement inside of a mechanical room. Then I can use the floor drain for the relief line.
> 
> Our pressure here in some places touches 160. I use a Watts brand PRV. (25AUB)? I think that is the right number. Besides, we both know if the heater bust, the pan is nothing but in the way.


 Not here, we use 1.5" pan drains and they will handle the flow.:thumbsup:


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## Plumber Jim

SummPlumb said:


> Good question....I have never put a gas WH in a pan. If I did, I would prob use a metal one. We cannot put relief lines into pans here. They make us pipe them all out here. Most of the time, the gas WH is beside of a furnace in a basement inside of a mechanical room. Then I can use the floor drain for the relief line.
> 
> Our pressure here in some places touches 160. I use a Watts brand PRV. (25AUB)? I think that is the right number. Besides, we both know if the heater bust, the pan is nothing but in the way.


I believe the 25aub has a thermal bypass but if you have city pressure at 160 it don't matter you need those expansion tanks. more money for you hehe


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## TheMaster

Heres a 1.5" pan drain


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## njoy plumbing

Mike Jessome said:


> is it I was taught wrong or do you have a potable expansion tank on the cold side I was taught to put them on the hotside... am I missing something here...


 Cold side, but should go before the shut off. Also a check valve if you check out install manual.


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## njoy plumbing

service guy said:


> Are you saying it doesn't matter which side then?
> I still think installing it on the hot side will wear it out faster than the installing it on the cold side. The tank manufacturers think so too.


 One of the main reasons for thermal expansion is to prevent unnecesary t & p leak by. D.W'S & A.W'S have solenoid valves that slam shut causing expansion in some systems. Just saying.:thumbup:


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## service guy

njoy plumbing said:


> One of the main reasons for thermal expansion is to prevent unnecesary t & p leak by. D.W'S & A.W'S have solenoid valves that slam shut causing expansion in some systems. Just saying.:thumbup:


So what? That has nothing to do with installing it on the cold inlet or hot outlet of the water heater. As long as there is no valve between the expansion tank and the heater tank, then the expansion tank will do its job and prevent thermal expansion from causing pressure surges.
THE ONLY reason for installing it on the cold side, is that the bladder will last longer exposed to lower temperatures.


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