Can anyone help me identify what's wrong with my Febco 825Y Backflow Valve?

[Bandit959]

Hi Folks;
I'm hoping that someone can help me out. I'm having some issue with be Febco 825Y (3/4") leaking from behind the relief valve. I've been troubleshooting it for a while and I'm stumped. Here's what the leak looks like.

So a bit of history.
- I'm not the original owner and it looks like the backflow valve was installed upside down. That will need to be addressed once this problem is solved.
- I went to pressurize it a couple weeks back and noticed the relieve valve was cracked. Probably from being upside down through the winter. (Bad one is on left, replacement on the right.)


- I ordered a new relief valve and a complete replacement gasket set. Skipped the discharge shield for now.
- I completely disassembled the unit, checked for debris and found a couple pieces that I removed.
- While the relief valve plate was removed, I used pressurized air to clean out the 2 small channels. I don't know the proper name but they are what the 2 plastic tubes connect with in this shot. I believe they pressurize the relief valve.


- Replaced every gasket and the relieve vale.
- The check valves were not cracked and the springs were not corroded so I didn't replace them. I did replace the rubber gaskets.
- Disassembled the replacement relief valve to check the o-ring (just in case) It was good.
- Reassembled the unit and slowly pressurized.
- When I pressurize the system, you can see the relief valve closes but I still get water flowing from behind it.

I don't have a pressure gauge so the only way I can check if the first check valve is operating is to open test cock 4. Although, the relief valve is closing so I suspect that the text valve is OK. For completeness, you can see what happens when the test cock is open.

Any thoughts would be greatly appreciated!

 

[Geofd]

Well you have to close that test port,that's supposed to be closed,it's hard to see the check valves what does the rubber look like are there imprints cut into the rubber

 

[Bandit959]

Well you have to close that test port,that's supposed to be closed,it's hard to see the check valves what does the rubber look like are there imprints cut into the rubber

Thanks for getting back to me. I think the first video may be what you're looking for because it has the test cock closed. It shows that the relief valve is closed but water come from the behind it. Here's that link

The video with the test cock open came from this troubleshooting video I posted it hoping that someone would see something that helps.

Sorry I wasn't clear in stating what I replaced. The gasket for the relief valve is brand new and doesn't have any tears or rips in it. I bought a rubber rebuild kit and I replaced every gasket.

 

[Twowaxhack]

Replace the entire assembly. It may be damaged from freezing.

 

[Geofd]

Replace the entire assembly. It may be damaged from freezing.

That's a good possibility......

 

[Geofd]

Thanks for getting back to me. I think the first video may be what you're looking for because it has the test cock closed. It shows that the relief valve is closed but water come from the behind it. Here's that link

The video with the test cock open came from this troubleshooting video I posted it hoping that someone would see something that helps.

Sorry I wasn't clear in stating what I replaced. The gasket for the relief valve is brand new and doesn't have any tears or rips in it. I bought a rubber rebuild kit and I replaced every gasket.

Watts 800 is a much more common backflow device. Is the device lower that the highest head????? There are 2 styles of backflow devices, one when the heads are higher than the device,one when the device is higher...it make a difference

 

[Bandit959]

Replace the entire assembly. It may be damaged from freezing.

That's kind of what I was afraid of. I'm not sure what else I can do with it.

 

[Twowaxhack]

That's kind of what I was afraid of. I'm not sure what else I can do with it.

Sounds like you rebuilt it properly. That’s all you can do.

 

[Bandit959]

Watts 800 is a much more common backflow device. Is the device lower that the highest head????? There are 2 styles of backflow devices, one when the heads are higher than the device,one when the device is higher...it make a difference

The device is lower than the highest head. I think that means the Watts 800 won't work in my case?

 

[Geofd]

That's correct, so your best bet would be a watts 909 if you do repipe put unions on so you can remove it during the off months

 

[Bandit959]

Problem solved.

It turned out to the be replacement part from the vendor. The gasket that was just out of round. I pulled the old gasket from the bad relief valve and put it on the new replacement part. And that took care of it.

In retrospect, the leaking coming from behind the relief valve should have tipped me off. I should have been more insistent with the vendor that their part was bad. But I learned a lot about this unit and can probably help out anyone with their now.

Thanks everyone for your thoughts.

 

[Geofd]

Nice save!!!!!!

 

[Bandit959]

That's correct, so your best bet would be a watts 909 if you do repipe put unions on so you can remove it during the off months

It turns out I don't need to replace it. The gasket in the new part was bad.

BUT I will use your suggestion and install a couple of unions when I reorient the valve to be the right way up.
Thanks!