Any experts in finding crossovers? Hot going to cold

[Geofd]

I hope our sinks don't have crossover issues, that would make things so much more complicated

All this time, every single crossover we've had in the hotel tower came from the shower pressure balancing units.

Your commercial kitchen faucets?????

 

[Pcmaker]

Is your commercial kitchen on the same
Riser......just thought of something else you must have a commercial laundry sometimes an electric solenoid valve can
Go bad,
Do you have soap injected washing machines, if so do you have testable backflow devices you would need rpz not double check devices

No, the tower is kinda separate from the casino. There's nothing in these lines but hotel rooms and mop sinks. We don't get any hot water issues anywhere else except for the end of the hotel tower

 

[Pcmaker]

Your commercial kitchen faucets?????

Nope, the commercial kitchen stuff is in the casino building, we dont' have any issues over there. Hot is hot, cold is cold.

I'm almost 100% certain it's a hotel room shower cartridge that's letting cold cross over to hot, but the problem is finding the exact room with the bad cartridge.

 

[Geofd]

Your commercial kitchen faucets?????

I don't think it's the shower valve it's just that the valve has the hot and cold connected it's like it's one pipe, one thing you could try is putting check valves on the hot and cold and see what happens
But that won't solve your issue there is something being overlooked. Go thru the posts, make a list check things we talked about check one thing at a tim e start simple

 

[Pcmaker]

I don't think it's the shower valve it's just that the valve has the hot and cold connected it's like it's one pipe, one thing you could try is putting check valves on the hot and cold and see what happens
But that won't solve your issue there is something being overlooked. Go thru the posts, make a list check things we talked about check one thing at a tim e start simple

Yeah, not the shower valve itself, but behind the shower cartridge is this thing called Pressure Balancing Unit. The only thing that prevents one side from migrating to the other half is a diaphgragm. Here's what it looks like and this is behind every shower cartridge in the hotel.

You can tell it's bad if you put your mouth over one hole, then cover the outlet on the other side. If it's good, air will not come out. If it's bad, you get air coming out the other side.

Here's a brief video of someone with a bad PBU

 

[Geofd]

Then the only thing I could suggest is spring loaded check babes on one or both sides ( hot/cold)withball valves, and unions that would stop the migration

 

[Geofd]

Valves.......

 

[Geofd]

Would also talk to kohler see what their remedy would be were you don't know which valve is crossing over

 

[frodo]

Or maybe you could shoot an infrared thermometer at the hot and cold supply inlets.
While the stops are still open.

The valves that are passing would be different temp than the rest on the stack.

I think Jeff has the ''quickest'' way of finding your cross connection.

 

[Mitchell-DIY-Guy]

OK, my guess is that the reason why all four stacks appear bad now is that due to laying off half the maintenance staff, things went unreported. If this were my responsibility, I'd replace them "a stack at a time".

Now, what I would also do--but I don't know how to do this--is to devise a test rig/jig to test the cartridges for leaking. Put each cartridge in a test valve, and test for leakage across the pressure balance. My guess is you'll find some are bad, some are good--then you can build a reserve of known working parts.

Now, if you cannot figure out a way to test these, then what you want to do is consider "rebuilding" all of them, with all new gaskets and o-rings. See the attachment for an example of the needed O-Rings. You can probably source them in bulk at a negligible price. While you're at it, if there are any other O-Rings or seals in the entire valve assembly replace those too.

https://support.kohler.com/hc/en-us/articles/360025913334-Pressure-Balancing-Unit-PBU-

 

[Pcmaker]

Thanks for all the help, guys. We have pallets and pallets of new cartridges, so that's not an issue. I'll email Kohler and as them if the new model PBUs don't have the crossover problem like the older models.

 

[breplum]

I definitely and positively have experienced crossover bleed with the K-304 which was completely solved by replacing the PBU, just like the youtube video describes.

 

[Pcmaker]

I wonder if Kohler fixed the issue with the old style PBUs crossing over. The new ones look very different.

 

[Geofd]

I wonder if Kohler fixed the issue with the old style PBUs crossing over. The new ones look very different.

I know there alot of valves your working with so this can't happen again could you pick 1room and cut check valves in????

 

[Pcmaker]

I know there alot of valves your working with so this can't happen again could you pick 1room and cut check valves in????

It would be a major remodel to access the copper lines and would have to do every single room

 

[Jeff Handy]

At least this gives you job security!

 

[Pcmaker]

Yeah, I'm up to my eyeballs in plumbing projects as it is

 

[Geofd]

It would be a major remodel to access the copper lines and would have to do every single room

I understand that just figured you could try one rm and see if that cured the problem for that rm at least you would know that check valves would or would not help