Drain hot water tank

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NKaufman

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Hello,
Have a Bradford-White water heater and am looking to drain it. Shower caulk has some yellow stain on it coming from shower water, suggesting that maybe hot water tank has mineral deposits, hasn't been drained in a few years.

The steps outlined in the manual are:
1. Rotate the thermostat dial clockwise to the lowest possible position.
2. Rotate and partially depress gas control knob clockwise to the “OFF” position.
3. Shut off the gas supply to the water heater ----- I might skip this step
4. Close the cold water supply shut-off valve.
5. Open the drain valve on the water heater by turning the knob counter-clockwise. The drain valve has threads on the end that will allow the connection of a standard hose coupling.
6. Open a hot water faucet to allow air to enter the system ----- why do we need to do this?

Then after water is drained, the fill steps are:
1. Close the water heater drain valve by turning the knob clockwise .
2. Open the cold water supply shut-off valve.
3. Open several hot water faucets to allow air to escape from the system.
4. When a steady stream of water flows from the faucets, the water heater is filled.
Close the faucets and check for water leaks at the water heater drain valve, combination temperature and pressure relief valve and the hot and cold water
connections

But the manual now has something as a Warning
Wait at least 2 minutes after this control is pressurized with gas before attempting to light pilot and/or push igniter button. Failure to do so may result in serious injury.

What the heck does this refer to in the steps for Draining and Filling Tank?

Any inputs/suggestions/advice on things to look out for before starting on this?

Thanks
 

NKaufman

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Another question - The instructions in my manual do not say anything about T&P valve open and close in Drain and Fill.

Is this required? Have seen some posts where people have opened T&P valve.
If not needed then I don't want to complicate this effort lol
 

Terry

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1. Rotate the thermostat dial Counter Clockwise to the vacation setting. That allows the pilot light to stay lit.
2. Skip
3. Skip
4. You can attach a hose while the cold supply is still on and forcefully blast some water out of the drain at the bottom, just to make sure that sediment hasn't clogged the drain. When it's clear that water comes out well, then you can close the cold water supply shut-off valve to the water heater.
5. Open the drain valve on the water heater by turning the knob counter-clockwise. The drain valve has threads on the end that will allow the connection of a standard hose coupling.
6. Open a hot water faucet to allow air to enter the system ----- why do we need to do this?
To empty a closed container, you also need venting. Have you ever held your finger over a straw, and the liquid didn't drain until you lifted your finger off of the top of the straw. You can open a few hot water faucets to make it drain quicker.
When I'm doing a pipe repair in a home I make it a point to open faucets so that the house drains the pipes down quicker. Sometimes it's taking a long time to drain so I go back to check the faucets and find that the homeowner was "closing" faucets behind me. Hey! How long do I have to wait to start cutting pipes? Let me drain your home down.

If you open the T&P, make sure you have a new one to install. Very often, once you play with it, it won't reseal. So that being the case, have a new one on hand. Or just leave it alone like we do.

It is a good idea to test them, but only when you have the replacement on hand.

rheem-gas-control-02.jpg


wh-gas-valve-resideo.jpg
 
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NKaufman

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Thanks Terry.

Is this to be done when shower bath tub caulk has a yellowish/reddish color on it suggesting that hot water tank needs to drained?



also, what does the Warning in the following mean?

1668969737634.png
 

Terry

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If you follow my directions, and turn it down to vacation, the pilot stays lit, the pressure is still on, and the warning no longer applies because you are no longer relighting the water heater, just turning the thermostat back up when done.

Or you can add a few more steps, steps the plumbers don't waste time with, and be careful when relighting the water heater.
 

NKaufman

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Thanks Terry
So the Newbie steps are:
Rotate the thermostat dial clockwise to the vacation setting. That allows the pilot light to stay lit.
Attach a hose to drain plug while the cold supply is still on
Open a hot water faucet
Open drain plug
-->Once water comes out, at what point do I turn off cold water supply?
-->How long should I let the water drain? Till nothing comes out?
Then close the drain plug
open a few more hot water faucets
Turn on cold water supply
wait till all hot water faucets have water coming out
 

Terry

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Rotate Counter Clockwise to the vacation setting. I had written Clockwise, but that was wrong.
I like to connect the hose to the drain and run some water out under pressure just to make sure the drain isn't plugged.
When I know the drain works, Open a hot tap, and turn off the water to the water heater. It will drain slowly until empty,
After it's drained, close the drain at the bottom, and refill the tank. I find that using the tub faucet is best. It's quick and it doesn't have an aerator that can get clogged with sediment. Once the tub is running for a minute, go back to the water heater and rotate the gas control back to where you want it.

rheem-gas-control.jpg
 
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NKaufman

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thanks again Terry

Clockwise seems to be correct for my model. That's what the manual I posted earlier also mentions.

Which hot water faucet should I open while doing this? The topmost floor or one at the same level as the water heater?
 

Master Plumber Mark

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Sometimes, when you attempt to drain your water heater you are going to get yourself in troubles...

I get LOTS of folks calling me telling me they did this and now the water heater wont fire back up again.
and they need me to come out and help them and then it gets expensive...

I tell folks to leave the gas on and turn the dial up to high,,, and let the unit heat up
Put a hose on the drain valve and secure the other end into the drain so it dont flop around everywhere

dont turn off the water ... dont turn off the gas and leave it alone ....
then open up the drain valve and BLAST out the sediment with full
pressure.... turn the drain valve on and off a few dozen times for maybe 20 seconds each time to help stir up the junk on the bottom of the tank... with the heater boiling the sediment will get thrown off the bottom and most or some of it will get sucked out the faucet...

I tell them its like you are trying to piss out a kidney stone....
 

Terry

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I like Mark's way. The question was about flushing the tank. So use Mark's way to flush. Mark also sells and installs water softeners, so he has a lot of knowledge about water heaters. Some of the tools for his vans for taking water heaters up and down stairs are amazing.

Thinking back to what I wrote, there was no reason to turn the water off. You want the old water out of the tank, and what better way than just push it out through the bottom using some force. Mark has a picture of a water heater that he's cut open, just to show what collects in his part of the country. I can see that flushing is important there.

I'm in the Seattle area, with our city water, we don't have softeners. We can get by without flushing really.
But that is not the case in other parts of the world where the water can be so different. I remember visiting Hanford California and smelling their water for the first time, the hot side was the worst. Kind of a wake up call for someone that has used water from the Northwest Snowpack his entire life.
 

Reach4

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When I changed houses, the WH had about 14 years under its belt. I went a little nuts cleaning. I got out an amazing amount of crud including rocks, which I should have saved. They have probably grown in my mind. After all, they had to get thru the screen of the submersible pump. See post #13 of https://terrylove.com/forums/index.php?threads/proper-gas-hot-water-tank-flushing.62015/ for some pictures.

As part of my process, I replaced the plastic drain valve with a ball valve.
index.php


I pulled the anode, and alternated spraying water down the anode hole and via the normal fill way thru the dip tube.

My process was many many hours long.
 
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Terry

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And most plumbers pull and toss a water heater at 15 years.
The last two gas tank water heaters I had didn't quite make it 15 years.
 
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NKaufman

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Mark - Should I turn off/on Drain valve till I see clear water coming out? Is that when I stop?
Should one do this process for a few times, wait to get sediment to settle down and repeat?

Thanks Mark and Terry for your suggestions.

This water heater is 18 years old and still works great. Multiple people can take showers (teens usually take LONG LONG showers until our throat hurts of screaming lol)

The only issue I have is shower caulk has a red/pink color that we clean every few weeks. Think it might be sediment from hot water.
 

Reach4

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Mark - Should I turn off/on Drain valve till I see clear water coming out? Is that when I stop?
Should one do this process for a few times, wait to get sediment to settle down and repeat?

Thanks Mark and Terry for your suggestions.

This water heater is 18 years old and still works great. Multiple people can take showers (teens usually take LONG LONG showers until our throat hurts of screaming lol)

The only issue I have is shower caulk has a red/pink color that we clean every few weeks. Think it might be sediment from hot water.
1. If sediment is still coming out, don't stop yet. Otherwise, 5 gallons, or so, seems about right to me. I am not a pro. Is this one of those round plastic drain valves? You cannot get much drain flow with those. I replaced mine with a higher-flow solution. If considering replacing your drain valve, say so. I doubt that you are considering that.

2. Pink caulk/grout may be something growing. https://www.forbes.com/home-improvement/bathroom/pink-mold-in-shower-causes/
Consider one of the bathroom cleaners that contains chlorine bleach, or maybe make your own mix... maybe 1 tablespoon of bleach in a cup of water, plus add some detergent.
 

NKaufman

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you cant beat a dead horse and expect too much to come from doing it, especially if the unit is
18 years old.... you can flush it and see what comes out but there is a possiblity you
will do more harm than good...

you cant squeeze blood from a turnip or is that an onion??
Not sure I understand that logic.
Are you saying that because the water heater is 18 years old, it should be replaced even when it is working fine without any issues?

On Nov 20, before several replies came here, I tried the method in the manual,
turned off water,
put dial on vacation setting
turned on one hot water faucet and
connected hose to drain plug on water heater. Saw just clear water come out, no debris, nothing. turned off after 5-7 minutes.

Might try your approach if you think that would force debris/gunk out (if there's any)

Showerhead also has some yellow deposits that I cleaned out by tying to it a zip-lock bag with vinegar, left it on for a couple of hours and cleaned out with a brush.

Thanks
 
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Reach4

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On Nov 20, before several replies came here, I tried the method in the manual,
turned off water,
put dial on vacation setting
turned on one hot water faucet and
connected hose to drain. Saw just clear water come out, no debris, nothing. turned off after 5-7 minutes.
I think you misread the manual.

You should have drained from the WH tank drain valve, and not from a faucet. The drain valve is at the bottom of the tank, where sediment hangs out. Your faucets are supplied by the top of the tank.
 

NKaufman

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I think you misread the manual.

You should have drained from the WH tank drain valve, and not from a faucet. The drain valve is at the bottom of the tank, where sediment hangs out. Your faucets are supplied by the top of the tank.
Thanks for catching that. I updated the previous post to reflect that I indeed connected hose to tank drain plug, not faucet..
 

John Gayewski

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My water heater is from 1986. I would not flush it. The only reason its still going is because I'm curios and I don't think itll do anything but start leaking on my basement floor which is fine.
 
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