Where to buy expansion tank?

[muleman51]

Pex Suppy told me I need 96 gallon expansion tank for 1050 gallon total. They said they don't have one that large. I have a Watts ET90 now. Where can Iget one that size.Thanks Jim

 

[MrEd]

I've never seen one that large, and I know others here are using the 86 gallon one for 1000 gallons of storage which is available (though backordered) from Pexsupply. You can always use more than one to get to the desired volume. Multiple small ones work just as well as one large one.

 

[muleman51]

There has got to be an alternative that can be used. I had aquote of around $700 for a tank thats more than I have in the 1000 gallon tank. Can a person use a plain non bladdered pressure tank like thy use on a well.

 

[machinistbcb]

I am using two non-bladder expansion tanks that are 80 gallons a piece. They came out of a old elementary school's heating system. I think you can use old electric water heater tanks. There is a good post on how to set them up.

 

[MrEd]

I have read the other post about how to make them, and I coincidentally have a tank that I could use, but the one part I still don't get is why it is OK to leave all that water in contact with the air in the expansion tank when the exp tank doesn't have a bladder?

I have a $500 expansion tank on back order, and I'd love to make my own(and save themoney)...I just don't want to corrode my entire heating system in order to save a few $$$.

Seems there is a lot of talk on how to get air out of your system, and the importance of doing that(i.e. making sure you use o2 barrier pex etc)...can someone convincingly explain why letting all this air be in contact with the water won't be a problem? I am not disputing this point, but I just don't get why it doesn't matter....