I have a Whirlpool gas water heater that is probably a bit too old but working well other than a blockage problem at the drainage valve. I have just replaced the relief valve due to calcium build up, but the drainage valve at the bottom is not draining properly. Obviously, it's probably due to the same calcium build-up issue.

Apart from replacing the unit, I would like to keep it as long as possible. Are there any remedies to preserving the water heater with this condition?



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Have you tried unscrewing the drain valve?

I have unscrewed the stop to open the drain valve, but water does not drain as it should. It actually just trickles out even though the tank is full.

I have attached a link to a picture. Are you suggesting I unscrew the valve with a full tank? I can turn it off, but it will be difficult to drain normally.

What is advisable at this point? Thanks.

I leave the tank full , the water on and open the drain. 50 PSI will usually blow out any debris that's trapped in there.

Interesting, NCPlumber. Are you saying the water pressure from the outside main (though the house) @ 50 PSI will create the additional pressure needed beyond the pressure from the water sitting in the tank? And then blow it out through a hose attached to the threads of the drain valve?

BTW, the house water pressure is about 50 psi after installing a pressure reducing valve out front, so that pressure value is what I would see at the water heater.

usually opening the drain with the cold water to the tank left on will blow out any debris.
I don't think I would try to remove that plastic valve. it may break at the tank threads. this would be an easy fix but the entire contents of the tank will come out like niagra falls.
these are the best valves should you decide to change it.

The suggestion/s partially worked.

After opening the drain valve with the intake valve open, the minerals seemingly were blown out and the hose diverted water like it would when attached to a regular spigot. Good.

The problem was when I turned the intake valve off to drain the tank in order to replace the drain valve, it stopped letting water out of the drain valve in the open position. I can't drain the tank as of now.

1) Should I use some type of wire brush through the open drain valve to help clear the sediment? Which one?

2) Should I unscrew the drain valve off the tank threads? Very messy and all new drywall, but I could do it, if necessary. I would probably use a 5 gallon bucket and try to replace drain valve while water is shooting out. I would first turn the gas off and open the intake valve to drain the hot water through the hose and replace it with room temperature water and then attempt the replacement. I'm hoping this isn't necessary.

Any other suggestions (apart from a new water heater)? Thanks.

That plastic drain valve MIGHT unscrew, but it is just as likely to snap off, so it would be safer to drain the water first, since it will be hard to remove the remainder of the valve from the tank with water running past it.

Ok, drain it first, but it will not drain as of now. It will cycle water through the tank if the intake valve is open, but it will not drain without incoming water (and its pressure). That's why this is weird. The drain valve acts like it's blown open after supply water/pressure comes into the tank, but will not retain a passageway for the open drain valve when the intake is shut off (to drain existing water and perform replacement).

The drain valve is right at the bottom. Maybe there just a lot of sediment. I think the water heater is about 7 years old.

Should I use a pipe cleaner type of wire brush through the open drain valve? Keep trying to open/close intake valve to dislodge sediment? Or risk the removal of the drain valve with a full tank (of room temp water)?

you need to open a hot water faucet upstairs to let air into the piping so the unpressurized tank can drain.

Too funny, packy! Of course, I needed to let air in from above. Venting 101, I guess. With the gas turned off what I have done is

1) Closed the intake valve and opened the outgoing hot valve
2) Opened a water faucet in the hot position in the kitchen, and
3) opened the T&P valve (which is gurgling air in the T&P downspout outside the house)

The result, the tank is now draining! Thanks for all the help!

Is there a maintenance suggestion at this point apart from changing the drain valve? Worthwhile to change the anode rod? Anything else?



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you don't have to change the drain valve now that you have passed the 'tank draining 101 course'..
replacing the anode rod is a good idea.
watch a few you tube videos to get some hints in your next plumbing course called 'anode rod replacement 101'..

After you turn off the water supply valve, you have to OPEN the T&P valve on top of the tank so air can enter the tank.

Thanks again for everyone's help! Problem solved and new brass drain valve installed.