Broken cold water shutoff on water heater

[Auntie Jojo]

Can a broken or non-functional cold water shutoff on a water heater cause crossover/cross connection symptoms?

I haven't had time to repair it yet, but when I get to it, I'll find out and post results here.

But does anyone have actual experience with this?

Thanks!
jojo

 

[Jadnashua]

No...it only has an input and output. I'm assuming you're talking about the handle being broken. If anything else was broken, you'd either have no flow, or it would be leaking onto the floor.

 

[Sponsor]

 

[Auntie Jojo]

Thanks, Jim. Darn. Wishful thinking that it would be something that simple. Yes, it's a gate valve and it no longer stops cold from coming through into the water heater. I have to turn off the water main valve inside the house when I drain the water heater or it just keeps on filling up. I'll replace that 1950's-era valve anyway--it does drip a little and I have a nice ball valve right here.

I hate to admit that my crossover is probably due to the new setup I put in--cold and hot supply lines each to its own T, whereupon one set of hot/cold goes to a wall-mount tub filler faucet, the other hot/cold branch goes to a shower/hand shower valve. I might have to nuke the tub filler if I can't figure it out. OR maybe once I make these valves operational, everything will sort itself out. I'll play with it after Christmas.

 

[Smooky]

You didn't Tee the hot and cold together did you?

 

[Reach4]

You may be able to figure out where the crossover is occurring by feeling the pipes at the fixtures while the crossover is occurring. If hot is crossing over to cold, expect the fixtures with the warmest cold pipe to be the place of the crossover.

 

[WorthFlorida]

Pictures would sure help on your explanation of tees. I think you mean you have a tee for the cold water going to the shower and the other part of the tee goes to a tub filler faucet and another tee for hot water line going to these same faucets. It sounds like you have a house built in the 1950's and may have old fixtures in use. Two common areas that can cause your so called crossover is an old washing machine valve where the hot and cold could mix and flow backward and old single lever faucets. What you need to do is close the hot or cold valves one at a time at each fixture until this crossover stops. Then you have your trouble area to look into. What type of bathtub or shower fixtures you have?

 

[Jadnashua]

A gate valve can fail when the gate separates from the stem. Don't think there's much else to do except replace it. My preference would be a ball valve.