RPZ or check valve on fill line?

[Telnet64]

Hi, here's my original setup from the builder:

Auto-fill line is tapped into water line at a hose bib, inside the house wall - just below hose bib. The auto-fill line has an RPZ (Watts 009-QT) mounted on a wall around the pool equipment. The way that the water lines were mounted in the equipment area have always created a number of problems keeping the pad area clear of leaves, debris - and snakes. So, I have removed all the excess water lines and am making a simple above ground loop at the edge of the pad, where the supply from the house and the return to the auto-fill are located. I am using the existing ball valve for on/off to the line.

My question is whether I really need to use the RPZ, or can I just install a simple check valve on the line after the ball valve? I know the RPZ is code, but interested in the real risks involved and probability of them occurring. FWIW, my neighbor just has a simple check valve and works fine for him (he's an engineer).

 

[JoyfulNoise]

You can do whatever you like but, when you sell the house, you’ll have to bring it back to code compliance. All of my external hose bibs came with backflow preventers on them and they all leaked making a water tight hose connection impossible (water would spray out and constantly drench my walls). Well, they are all gone. If/when we ever sell our home, I’ll be spending a few hours doing some amateur plumbers work to replace the non-leaking hose bibs with the original leaky ones with attached backfkow preventers.

 

[Telnet64]

Thanks for the reply, I have those as well - attached to the end of the hose bib. The RPZ on the fill line is this monster.

Also, in terms of safety, the line from the house to the pad is probably 50 feet, so I would think (could be wrong) that the distance mitigates any threat of back flow into the house lines.

 

[kadavis]

This is what I see more often than others. Google or some use a dual check valve like,Google

 

[JoyfulNoise]

This is what I see more often than others. Google or some use a dual check valve like,Google

I have that first one on my irrigation loop off the house main and that second one on my autofill line.

What’s hilarious is that code requires the backflow/vacuum breaker connections on irrigation lines and yet, for residential homes, there’s no annual testing requirement. So I’m willing to bet these units get installed at great expense to homeowner only to have them fail or not operate properly anyway. Another one of the typical regulatory “solutions” in search of a problem...grew up my entire life in my parent’s home with well water and outdoor spigots connected directly to the supply plumbing....they managed to survive and raise 2 generations of a family for 40 years in that home without “backfkow” issues....

As I said, my non professional advice is to do what you think works best and just keep all the old components so that you put it back to code compliance if you have to sell...

 

[Telnet64]

kadavis - thanks for those links, very helpful

Matt - agree that it's somewhat ridiculous since there's no testing enforced. I'll keep the components and also consider the second valve (much cheaper than the Watts 009 QT). I made the changes this weekend with a cheap Home Depot PVC check valve and all seems good.

 

[Telnet64]

I'm not sure if it's acceptable if I resurrect my own thread, but it seems to be provide all the 'history', so I hope it's ok.

As I posted separately, my equipment pad froze in the big TX arctic blast last week and i had some broken valves (cheap kind) at my UV light (now gone) and on my fill line, at the on/off valve (PVC).

So since I have to rebuild the fill line and it's on the edge of my pad, I am thinking about moving it underground, using a sprinkler access box. My pool is a couple feet below the pad elevation, the spa is part above and part below.

I'm also, thinking I will change to a brass on/off valve, like this and to the previously mentioned brass check valve here.

Any suggestions are welcome.