New Expansion tank installation....necessary ?

[SewerRatz]

I do not agree that a well tank is a suitable expansion tank. Since it will not meet the letter of the code here in Illinois. Bold added by me. I do agree that the well expansion tank can handle the job, but we must follow the plumbing codes in our local areas.

A properly sized and approved expansion tank shall be located on the outlet side of the check valve in the water heater's cold water supply with no shut-off valve between the heater and expansion tank.

 

[rcatty]

My reading of the code indicates that an expansion tank is required on "closed" systems only. My understanding is that a closed system means one that has a meter, check-valve, or some other "back-flow prevent(er)" device, that would prevent water from backing up in the line.

Specifically, Ill Admin Code sec 890.1130 g. 7 reads, in part, : " Closed water systems shall have a properly sized thermal expansion tank ..........."

I see no other Code requirement for "open" systems, or water heater tanks in general.

 

[Sponsor]

 

[SewerRatz]

My reading of the code indicates that an expansion tank is required on "closed" systems only. My understanding is that a closed system means one that has a meter, check-valve, or some other "back-flow prevent(er)" device, that would prevent water from backing up in the line.

Specifically, Ill Admin Code sec 890.1130 g. 7 reads, in part, : " Closed water systems shall have a properly sized thermal expansion tank ..........."

I see no other Code requirement for "open" systems, or water heater tanks in general.

As I said in other posts there is no requirement "YET" for "open" sytsems. I do think you meantioned you have a well right? Most wells have a check vavle, which makes it a "closed" system.

 

[99k]

Most wells have a check vavle, which makes it a "closed" system.

The check valve is installed between the feed and the well tank (prior to the cross) and therefore the system is not closed

 

[SewerRatz]

The check valve is installed between the feed and the well tank (prior to the cross) and therefore the system is not closed

99k educate me here a bit. I will admit my well knowledge is nill. So there is a check valve between the feed from the pump and the well tank. Prior to the cross, meaning that you are saying the well tank would act as your expansion tank? From what I am getting if thermal expansion happens the check valve will prevent the water from pushing back into the well. To me that is a closed system. But maybe I am missing something.

Lets do say you are depending on the well tank to handle the thermal expansion. It would not meet the Illinois plumbing code then. The part it violates is the fact there is a shut off valve between the tank and the water heater. Also I am not sure on this one but the code does say "A properly sized and approved expansion tank" is the well tank approved for thermal expansion? But that does not matter since it does not meet the requirement for the location of the expansion tank. "shall be located on the outlet side of the check valve in the water heater's cold water supply with no shut-off valve between the heater and expansion tank. "

 

[rcatty]

Ron, but what you quote above , refers/applies to "closed " system. My understanding of the requirement for a tank, is an effort to avoid pressure build-up , where the cold water has no place to expand. Hence, the requirement for the tank between the shut-off valve and the tank. If one were to close the line by closing the shut-off valve, then you would have pressure build-up. A system would become closed at that point. However, the Illinois code is not mandating a tank for every system. Just permanetely closed systems.

 

[Kingsotall]

The hot water would be the one doing the expanding. If there were a check on the cold side then in theory that cold line would then, yes, have no room to take any expansion from the hot side.