Lawn Sprinkler Leak - What is this part?

[dougand3]

Got a lawn sprinkler system on a separate meter. BIG leak this morning. This system does not have a regulator just after the meter like the house system has. This PVC Tee is blowing out the center at full force. I feel a felt pad/cloth screen on the Tee. Is it the regulator? Upstream PVC pipe = 1.30" OD. Tee = 2.00" OD. Downstream PVC pipe = 1.65" OD.
I've searched web and can't find a part that looks like it. Not even sure of the search term. Thanks, Doug

 

[CT18]

It is either 1" or 3/4" or 1/2" pipe. To me it looks like 1" going into a 1" tee and reducing to 3/4" on the right. I am not sure if the branch is reduced also, you need to expose it. You will need to dig up more of those lines to repair anyway.

 

[dougand3]

Thanks, CT18. More digging today.

 

[dougand3]

More digging. I find no pieces of a blue or black irrigation pipe in the cavern that the water blast created. Here is the threaded in part - felt cover with central hole. So, this is a pressure release that blew? I can find no part like this on the web.

 

[dougand3]

Got the male threaded 3/4" top plate off. It's a King Drain anti-freeze valve. Plumbing supply should have.

 

[dougand3]

You'd think you could get anti-freeze valve locally but plumbing and irrigation supply houses were befuddled about part. Seems they haven't used them for decades. And this install was 1989. Luckily, 1/2" PVC threaded plug worked just fine. I'll just drain it in Dec like everybody else does.