First DIY PVC plumbing - not on a pool!

[Melt In The Sun]

Hi all,
I'm fixin' to fix my sprinkler system (I hope!). This is one of those dumb situations where, for months (nine in this case), you overlook something that is really bad, then all of a sudden realize "Oh hey!! That's a problem!"

Below is a picture of our hack-job of a setup. It was this way when we moved in, and I didn't know any better . Now I do, mainly from stuff I've learned here on TFP. [attachment=1:xeflosb4]DSCN1333small.jpg[/attachment:xeflosb4]

The hose spigot goes to the splitter, which goes to the two solenoid valves with are oh-so-gracefully hung on the pipe behind the spigot. So, the issue is that garden hoses are not meant to hold pressure constantly. I am lucky that they haven't blown when nobody's home, flooded my yard, and jacked up my water bill.

I'm going to try to plumb a stub out from the autofill line (goes into the ground right in the middle of the photo) to which the solenoid valves will attach; see this work of art:
[attachment=0:xeflosb4]DSCN1333smallart.jpg[/attachment:xeflosb4]

The autofill pipe is 3/4 PVC, wrapped with insulating tape (I guess?). So in order to execute my plan, I think I'll need:
1. a PVC tee to splice into the existing pipe;
2. a short length of 3/4" PVC to run out to the right;
3. a few fittings (more tees?) to which the solenoids will attach (standard 3/4" hose thread), I'll probably leave space for some more solenoids if we want them later;
4. a new ball valve to put below, so I can still turn off the autofill independently of the sprinklers; and
5. the usual fixins such as primer, glue, etc.

Does that sound like a good (or at least workable) plan? I am planning on tackling this tomorrow afternoon. Thanks for looking!

 

[jcourt]

Melt in the Sun,

The original picture is one of the most interesting and risky set-ups I've seen. The only thing I'd add to your design is to ensure that you add a back-flow preventer on the supply side to keep the sprinlker water separate from your potable water.

Good Luck

 

[Melt In The Sun]

jcourt; thanks for the tip. I'm 99% sure the solenoid valves have them built in, but I'll make sure

 

[acamato]

Just make sure everything is supported. You don't want that new manifold cracking off.

Also, check your local building codes for the backflow preventer requirement. Some townships require double check backflow devices.

 

[Melt In The Sun]

Just make sure everything is supported. You don't want that new manifold cracking off.

Yep, thought about that. I expect it will need some support, but haven't decided how to do that yet. Thanks!

 

[Melt In The Sun]

Not to be a pain, but any more ideas/tips/scoldings from anyone?

 

[Melt In The Sun]

Since nobody had any more corrections, I had no choice but to assume my plan was perfection itself! :-D

Here's the result; haven't wired up the switches again yet. I managed to only spill a little bit of primer
[attachment=0:37nkdl5b]DSCN1336.JPG[/attachment:37nkdl5b]

Double check valves were not required. Thanks for the tips, jcourt and acamoto!

 

[bk406]

Just for the record, the solinoid valves do not have backflow preventers. In MITS picture, the backflow valve is the little doo-hicky with the white, round top on it to the left of the splitter he installed. However, even if not required, a double backflow is actually a good idea. They are expensive however. Makes me wonder who installed that mess. The valves are actually supposed to be installed in the ground using junction boxes, not on the side of the house. But, your fix looks much better. Putting those valves in the ground after the fact is a pain, and how you have it now, looks fine.

 

[Melt In The Sun]

Just for the record, the solinoid valves do not have backflow preventers. In MITS picture, the backflow valve is the little doo-hicky with the white, round top on it to the left of the splitter he installed.

bk406, thanks for clarifying that; I did figure that out before starting but never mentioned it. I was a bit thrown off, because that "doo-hicky" says "vacuum breaker" on the top, and since I'm new at this I had to look up what that meant! I assume the previous homeowner installed the mess I had before. Seems that the home inspector would have commented on it when we were in the process of buying this place, but...

Round here, nobody does in-ground valve installations; they're all attached to the plumbing outside the house. I guess that's unusual, but just the way that it's done in this screwy town.

 

[bk406]

Round here, nobody does in-ground valve installations; they're all attached to the plumbing outside the house. I guess that's unusual, but just the way that it's done in this screwy town.

That is kinda odd. Usually, depending on the number of zones, a couple of home runs that keep water in the lines at all times are run out to junction boxes that contain the valves. Each valve then runs one zone. I have 7 zones of yard irrigation and 2 zones of drip for all of the planting beds.