# Using water heater as a compressor tank?



## Green Country (Mar 6, 2009)

I've been considering using a wh as a tank for my compressor to give me more volume, is this a bad idea? I know they are rated for the pressure, but my cousin knows, well, knew a guy that died when he did this and it blew up.

I don't know the details of the incident, but if I leave the t&p in shouldn't I be ok?


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## Redwood (Sep 8, 2008)

You don't want to go there...


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## LEAD INGOT (Jul 15, 2009)

I think a 60 gallon standup air compressor is cheaper than a 50 gallon water heater anyway. Why end life with a bang?


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## rocksteady (Oct 8, 2008)

I've known people that have done that but I think I'd find something else to use. I see stand up compressors with burnt out pumps and/or motors for dirt cheap fairly often.





Paul


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## Green Country (Mar 6, 2009)

Redwood said:


> You don't want to go there...


Why not


And the wh I have out back is free


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## Green Country (Mar 6, 2009)

rocksteady said:


> I've known people that have done that but I think I'd find something else to use. I see stand up compressors with burnt out pumps and/or motors for dirt cheap fairly often.
> 
> 
> 
> ...


Yeah, I just missed a campbell hausfield 100g for $40 on craigslist.


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## user2090 (Sep 26, 2009)

We use water heaters as pressure tanks all the time when we winterize. Of course, we don't run the pressure above 60 PSI.


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## DUNBAR PLUMBING (Sep 11, 2008)

I'll take pictures of the one I have as a storage tank up in the rafters. 

I bought a bunch of richmonds aka rheem water heaters and out of 6 I have 2 left.

One I stripped out for parts and used as an air tank and the other 30 gallon gas (mobile home) one I'm waiting for a friend who needs it in his trailer.



I run 140psi in the tank, can't understand why the T&P won't open up. 


Oh that's right some dumba** took it out and put a plug in it. 

Idiot!:tt2:


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## M5Plumb (Oct 2, 2008)

Yup, don't go there....



Redwood said:


> You don't want to go there...


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## Green Country (Mar 6, 2009)

Can you guys that keep saying "don't go there" please tell me why?


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## SlickRick (Sep 3, 2009)

Green Country said:


> Can you guys that keep saying "don't go there" please tell me why?


Just don't go there.. I'm just sayin'


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## Plumber Jim (Jun 19, 2008)

Is saving a few dollars worth risking your life with a tank not designed to be used for storing compressed air? what if you are standing right next to it and it blows?


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## rocksteady (Oct 8, 2008)

Green Country said:


> Can you guys that keep saying "don't go there" please tell me why?


 
My thinking is that a water heater tank may be built to hold 150psi but it's not meant to have constant large fluctuations in pressure. I don't know if that's a big enough concern not to use one but with the possible failure of the tank and subsequent failure of your life, I wouldn't chance it. 





Paul


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## M5Plumb (Oct 2, 2008)

Where do you plan on putting this thing? Your shop? Is your shop a place of business? If you have the WH as an air storage tank, mounted with a compressor, how are you going to certify this system with the pop-off? Where is the certification placard of this unit as compressor? Is this an OSHA approved unit and is it UL Tested? 

I could go on but I think enough has been said.

One word though, *L I A B I L I T Y*



Green Country said:


> Can you guys that keep saying "don't go there" please tell me why?


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## Protech (Sep 22, 2008)

I don't see why it won't work (a new heater that is).

They are tested to 350PSI at the factory and designed for use up to 150PSI so why not? Air does not produce pressure spikes like a water system will from hydraulic hammer.

Heater tanks are glass lined and have anodes, compressor tanks don't have ether. What is so much better about an actual air tank?


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## rocksteady (Oct 8, 2008)

just thought of something. I was replaying the mythbusters episode in my mind when they blew a water heater through the roof. when the heater blew up it basically blew the entire bottom off of the heater and i think it did it at less than 300 psi (I'm not sure on this). the bottom of the heater was sitting right where the tank used to be. every compressor storage tank I've ever seen has rounded ends on it, not the flat ends that a water heater tank has. there has to be a reason for this. 

to me it just seems like something that isn't that hard to do with the correct materials, why even mess with it? 






paul


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## Protech (Sep 22, 2008)

I believe it was over 300PSI. As I said, heaters are tested over that pressure from the factory. Not that it matters. Most compressors only go up to 140.


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## nhmaster3015 (Aug 5, 2008)

Instead of a water heater tank, go with a 100lb propane tank. It will take all the pressure you can put to it.


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## gear junkie (Jun 20, 2008)

The air pump also has to be sized for the tank. If the the tank is too big, the pump has to run longer per "fill up" than designed. If the tank is too small, then too big a pump would short cycle and also cause premature failure.


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## Tango (Jan 13, 2018)

TradeMaster said:


> Yes,
> 
> 
> Yes, as long as you have T&P. Standard tank has 150 psi. If you need a little more pressure you could throw in a 200 psi. I too use my water heater to blow out irrigation every wither (hook up my dewalt) and, it drains crud out. Folks should do that 1nc a year anyway. But yes, yout'lll be fine! With T&P you won't blow yourself up. Most compressors have a built in one as well so you have a failsafe, still scared? Throw a tee in on water heater and have a failsafe backup.


Read the intro rules.


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## hensingstudios2 (8 mo ago)

Redwood said:


> You don't want to go there...


Had a friend years ago use a hot water tank as holding tank and it explosed... and in the process, messed up the side of vehicle he had just painted... dirt all over!


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## sparky (Jan 8, 2014)

Green Country said:


> Can you guys that keep saying "don't go there" please tell me why?


No one knows lolololololo they just saying don't go there


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## OpenSights (Mar 23, 2015)

hensingstudios2 said:


> Had a friend years ago use a hot water tank as holding tank and it explosed... and in the process, messed up the side of vehicle he had just painted... dirt all over!


Re read the forum rules and vet yourself.


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