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Discussion Starter · #1 · (Edited)
Video of the Day...toilet hooked to hot water heater

OK guys...when I got this call I did not believe it. Said there is no way for what they are telling me to happen. I WAS WRONG!

Now I do have a theory after seeing the videos (2) watch both, but this was too much fun not to share






 

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Hard to see for sure but the water appears to be coming from the PRV (the tag obscures it a little). Not sure why the PRV would operate even if hot water was supplying the toilet. I've run across this a couple of times (as well as a dishwasher being supplied with cold water).

What's your theory?
 

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Discussion Starter · #3 ·
Hard to see for sure but the water appears to be coming from the PRV (the tag obscures it a little). Not sure why the PRV would operate even if hot water was supplying the toilet. I've run across this a couple of times (as well as a dishwasher being supplied with cold water).

What's your theory?
Yes, you are correct, that IS the pressure relief valve.

OK, so my theory is...unconfirmed but this is what I think is happening.
Won't know till they call me back with some tests.

1) The hot water was shut off due to a bad PRV
2) The sink faucet is faulty and backfeeding an abandoned hot water line
3) When the toilet is flushed and water runs through the line, it fills the abandoned but not disconnected hot water line at the sink and sends it into what is now essentially a Storage Tank.

Hole in my theory - YEAH

Why is flushing the toilet causing the water at the sink to run?

Until I have them do more testing or see it in person...I can not be sure but funny **** just the same. :whistling
 

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is there a return line in the system. Is the drain line tied into the water lines? Wow it's a real x-file.

Ok, after a closer look.

The incoming cold water line feeds the toilet first than the water heater. I can see a check valve on supply line.

Combination of high water pressure.

A temperature and pressure relief valve with worn springs that will release with the slightest of pressure surges.

* ok I think i figured this out, since the water heater is plumbed after the toilet, after a flush happens, like I said above, the check valve right before water heater is probably going crazy with the pressure spikes. It's like turning the water on and off a 25 times a second. I dont usually see cold water supply lines running on the floor, but not a big deal.

I can only imagine that one day after flush that water heater will explode or burst open with a pressure spike. A thermal expansion tank might work, it's not really a thermal expansion issue.

Looks like a older toilet the 5 gallon tank type. So 5 gallons of water surging the lines after a flush, big time water hammar going on, after years of this the p & t valve finally gave up. I'm sure if you pop on a new valve, check the water pressure, check for thermal expansion, if fact if you can attach your pressure gauge to the drain valve, flush the toilet and I bet you will see 20-30 pound swings.
 

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Discussion Starter · #6 ·
is there a return line in the system. Is the drain line tied into the water lines? Wow it's a real x-file.

Ok, after a closer look.

The incoming cold water line feeds the toilet first than the water heater. I can see a check valve on supply line.

Combination of high water pressure.

A temperature and pressure relief valve with worn springs that will release with the slightest of pressure surges.

* ok I think i figured this out, since the water heater is plumbed after the toilet, after a flush happens, like I said above, the check valve right before water heater is probably going crazy with the pressure spikes. It's like turning the water on and off a 25 times a second. I dont usually see cold water supply lines running on the floor, but not a big deal.

I can only imagine that one day after flush that water heater will explode or burst open with a pressure spike. A thermal expansion tank might work, it's not really a thermal expansion issue.

Looks like a older toilet the 5 gallon tank type. So 5 gallons of water surging the lines after a flush, big time water hammar going on, after years of this the p & t valve finally gave up. I'm sure if you pop on a new valve, check the water pressure, check for thermal expansion, if fact if you can attach your pressure gauge to the drain valve, flush the toilet and I bet you will see 20-30 pound swings.
I couldn't see a pressure valve in the video, but your theory has less holes than mine. :D

I'm doing this voluntarily to help out a charity and they are out of state so I'll be checking this out - in person in a couple of weeks.
This is only 1/2 of their problem, but I think the rest of their problem is simply snaking the toilet line as nothing will flush. If that's doesn't work, I'll run a video inspection of the main waste line.
 

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Hi Larry,

I don't see a pressure valve. I see a temperature and pressure relief valve, the little guy sticking near the top of the tank, I also see a check valve on the bottom, on the incoming cold. A pressure regulating valve or prv would go on the incoming main water line. Thanks for helping out people, that is really good of you to do. I would if you don't have one already buy a $7 water pressure gauge at home depot, or you can ask the folks to buy one, you can return it later. Have them attach it to the drain valve. You can ask them to take some video of the pressure gauge when the toilet flushes. The valve that is releasing water, the pressure & temperature relief valve, those suckers are rated to hold at 120 to 140 psi or more, so if it's releasing now, that means it's failing. Sometimes they get old and just get worn out. However, if it gets too weak it will just release water 24/7. So I would elevate this check it out now. There might be a local plumber that can swing buy to take a look, tell him that you and the homeowner will right up a nice yelp review, or something similar.
 

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Discussion Starter · #8 ·
Hi Larry,

I don't see a pressure valve. I see a temperature and pressure relief valve, the little guy sticking near the top of the tank, I also see a check valve on the bottom, on the incoming cold. A pressure regulating valve or prv would go on the incoming main water line. Thanks for helping out people, that is really good of you to do. I would if you don't have one already buy a $7 water pressure gauge at home depot, or you can ask the folks to buy one, you can return it later. Have them attach it to the drain valve. You can ask them to take some video of the pressure gauge when the toilet flushes. The valve that is releasing water, the pressure & temperature relief valve, those suckers are rated to hold at 120 to 140 psi or more, so if it's releasing now, that means it's failing. Sometimes they get old and just get worn out. However, if it gets too weak it will just release water 24/7. So I would elevate this check it out now. There might be a local plumber that can swing buy to take a look, tell him that you and the homeowner will right up a nice yelp review, or something similar.
I was thinking about sending in my plumber I have under our PM company and donating the service, but I've donated a lot in 2013. Helped another charity buy a van. But since my income varies, I don't know that I could swing it. Wouldn't hurt to ask him.
 
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