Water pressure question

[49erinnc]

Relates to my hot water heater upgrades actually.

Got my new elements in, heater works great. However, after filling the tank back up with 50 gallons, I realized that my drain valve at the bottom is leaking. Nothing major but probably a cup of water every 8 hours. Enough that it needs to be replaced.

Question: If I cut off the main water-in valve to the water heater, leave the pressure release valve closed and keep all faucets in house closed, is it possible to remove the bottom drain valve and put in a new one without draining the tank? I understand that some water will still trickle out. But wouldn't the lack of air in the tank create somewhat of a vacuum inside the tank, thus preventing water from gushing out the drain valve?

Just curious if it's possible to replace that drain valve without draining the entire water heater again. Looking forward to the simplistic answer but also to MS Dawn's response as well.

 

[Demon-Xanth]

It'll be like opening up a bottle upside down, air will get in through the opening and bubble upto the top.

 

[Scarpozzi]

Gravity pwns any kind of vaccum since the valve is at the bottom of the tank.

 

[Scarpozzi]

Originally posted by: Demon-Xanth
It'll be like opening up a bottle upside down, air will get in through the opening and bubble upto the top.

Thank you Mr. Wizard, I like my answer better....cause Gravity is just cool like that.

 

[skyking]

of course you can. get a couple of bath towels. turn off all water as you suggested. get new valve ready with teflon tape on it. pull old valve and slap in new one. It will gush a few cups at most. Service guys change the elements like that all the time.

 

[FoBoT]

try it
make a video
post the video on youtube
give us the link

good luck!

 

[49erinnc]

Originally posted by: FoBoT
try it
make a video
post the video on youtube
give us the link

good luck!

It would only be worth posting on youtube if I tried to replace the drain valve without draining the tank AND did so without cutting the power to the hot water heater. Then it suddenly becomes more entertaining for the viewing audience.

On topic, if it's going to barely gurgle out, then I don't see the point in draining it. Especially not if service people replace elements without draining.

 

[skyking]

LOL, he BOUGHT it!!

He's offline now, mopping up the mess:laugh:

 

[49erinnc]

Originally posted by: skyking
LOL, he BOUGHT it!!

He's offline now, mopping up the mess:laugh:

At work now but will be tackling it when I get home. My hot water heater is in the garage, so worst case scenario is that I have a very wet concrete garage floor. It could use a cleaning anyway. It took around 2 hours to drain the tank last night to replace the elements so I'm willing to gamble on the valve without draining.

 

[funboy6942]

Mine leaks too. My vale has a threaded end on it so I bought a end cap for a garden hose ftw. If yours has a threaded end for attaching a hose to it, so you can drain the tank so it should, go to ace hardware and for 79 cents you can stop it from leaking.

I know I should just turn off my water and replace it but Im too lazy

 

[skyking]

Originally posted by: 49erinnc

Originally posted by: skyking
LOL, he BOUGHT it!!

He's offline now, mopping up the mess:laugh:

At work now but will be tackling it when I get home. My hot water heater is in the garage, so worst case scenario is that I have a very wet concrete garage floor. It could use a cleaning anyway. It took around 2 hours to drain the tank last night to replace the elements so I'm willing to gamble on the valve without draining.

oh man, you spoiled all the fun.....
you could have come back all F U and like drowned rat

nah, I worked for sears in another life, and they do yank elements without draining. if not, the customers would REALLY scream at the bill

 

[49erinnc]

Originally posted by: skyking


nah, I worked for sears in another life, and they do yank elements without draining. if not, the customers would REALLY scream at the bill

How do they do that with interior water heaters? I know that if you close off all air intakes, the spill will be minimal but those element holes (for the screw-in elements) are big holes (around 2" diameter). Just seems like they'd make a mess without draining. But I'm sure it's done because those guys would lose a LOT of money from spending 80% of their time on a service call just draining the heater.

Mine leaks too. My vale has a threaded end on it so I bought a end cap for a garden hose ftw. If yours has a threaded end for attaching a hose to it, so you can drain the tank so it should, go to ace hardware and for 79 cents you can stop it from leaking.

I actually considered this but the threaded end on my valve is virtually non-existent. There's maybe 1 full thread there, if that. I couldn't even get a garden hose on it to drain the tank without water shooting all over the place. If I had enough threads, I'd definitely take that route. However, the tank is pretty old so it can't hurt to replace the whole valve which is less than $4 at Lowes.

 

[Fern]

My hot water heater has a drain valve at the bottom (or very near). I just drain all the water out when working on it.

I OPEN all the faucets etc so as much water as possible can drain out as quickly as possible.

Fern

 

[AbsolutDealage]

I would do it the proper way and drain the tank first... but that's just me.

 

[BrokenVisage]

Better get a surge protector for that!

 

[Paperdoc]

Yeah, water will burgle out all over you, especially on your hands. You'll be madly trying to remove old valve and stuff new one in against the water as quickly as possible.

Problem I see is not water all over your floor - you already said that's tolerable. Problem is HOT water all over your HANDS! That will stop you cold (sorry, hot!!) and then you have an open hole leaking water and no way to reach in and stop it. If you wanted to turn off the power and let it cool down first you might get away with that, but the time for that would be much more than the two hours you are trying to avoid by not draining.

 

[Rubycon]

Originally posted by: Paperdoc

Problem I see is not water all over your floor - you already said that's tolerable. Problem is HOT water all over your HANDS!

Yes the tank should be drained. The insulation will keep that water at an uncomfortable temperature for a considerable time unless the setting is unusually low and/or the appliance is in a cold location.

You should change the TP valve if you have not already done so. And don't forget to pull the anode and examine its condition.

 

[skyking]

Originally posted by: Paperdoc
Yeah, water will burgle out all over you, especially on your hands. You'll be madly trying to remove old valve and stuff new one in against the water as quickly as possible.

Problem I see is not water all over your floor - you already said that's tolerable. Problem is HOT water all over your HANDS! That will stop you cold (sorry, hot!!) and then you have an open hole leaking water and no way to reach in and stop it. If you wanted to turn off the power and let it cool down first you might get away with that, but the time for that would be much more than the two hours you are trying to avoid by not draining.

shower up in the morning. turn off the breaker. change it out when you get home from work.