Water Heater Flush

[Spur08 382]

How many people actually do this maintenance annually?  I've been in this house 4 years and have never done it, mainly b/c I'm not too familiar with how my gas water heater works.  It has an On/Off switch and a circulation pump.  When I turn it to "Off", do I need to turn the gas valve off as well?  Any other things to watch for while doing the flush?  Do most people flush with cold water for a few minutes before closing off the valve and tightening everything up?

[bschoolprof 6273]

I don't think most people do this.  

I did this once to try to flush out some mineral deposits that were making noise in the bottom of the tank when the water heated up.  

It's probably a good idea to turn the gas valve off.  One thing to watch out for is you need to open up some faucets or the pressure relief valve in order to drain the tank.  Otherwise a vacuum can form, like pouring a fruit juice can without poking two holes.  Also make sure the hose  you are using to drain the tank let's the water out somewhere where kids won't get to it (it's hot).  Finally, once it's completely;y drained, turn the cold water on in spurts (on and off) to try to stir up the bottom and then partially fill it a little ways above the drain valve and drain it again to try to get the debris out.  Good luck.   

 

[Spur08 382]

Actually, not too bad. Just hope I got that bad boy lit.

 

 

 

[Jkwellborn 6749]

If I lived somewhere that had a well, I’d do it every year. Otherwise, I’m not fooling with it.

[milkman 428]

Here is a really good video of some water heaters getting cut open. Amazing the amount of sediment that accumulated in the tanks.

 

 https://youtu.be/kAzKts6Wp1Q

 

 

 

[Spur08 382]

That is pretty gross, Milkman.  Explains why my water was so cloudy for a period after the flush.

[phdhorn 6224]

It's kind of like a transmission flush on older cars:  Don't do it.  You'll just fuck things up and have to buy a new unit anyway.

I tried a flush once and got very little sediment. I think the valve was kind of caked over.  Or I have very clean ground water.

[woohorn 1131]

It's kind of like a transmission flush on older cars:  Don't do it.  You'll just fuck things up and have to buy a new unit anyway.

I tried a flush once and got very little sediment. I think the valve was kind of caked over.  Or I have very clean ground water.

Ha! My transmission hasn't been the same since a flush at 100k. Wish I had never done it.

My wh guy said don't bother flushing tanks because it will screw up the valves/faucets/whatever.

[Spur08 382]

I unscrewed each valve throughout the house and flushed the hot water line afterwards.  That alone probably was never done in the house as there was a lot of scale/rocks on the faucet screens.

Edited May 23, 2018 by Spur08

[Born to Run 6569]

I only recommend it if you get a lot of sediment build up generally. Ie your already having to flush your faucets out frequently.

[Spur08 382]

28 minutes ago, Born to Run said:

I only recommend it if you get a lot of sediment build up generally. Ie your already having to flush your faucets out frequently.

But won't regular flushing increase the lifespan of your heater?

[woohorn 1131]

Nah, but it depends on your water supply, I guess. I just replaced 2 (10 mos apart) that were 14 years old. No maint, no problems, except that the seams split and started leaking from old age.

[kangsta 50]

Had it done after Harvey and a week of no water supply + a broken water main this winter.. Still filled a bathtub with black water and then exploded upon itself right before closing on the sale of our house a month later.  Avoid that if possible.  

[BottleRocket 647]

Got mine replaced around 2010 and it rumbles and knocks like a got damn freight train.  Service tech said he wouldn't flush it because of the risk of damaging things down stream.  You would think that the thing was on its last leg but it keeps on rocking.  I'm not sure what the failure point will be to end its life but I'm ready to shoot it myself.

[Nice Guy Eddie 13528]

3 hours ago, woohorn said:

Ha! My transmission hasn't been the same since a flush at 100k. Wish I had never done it.

My wh guy said don't bother flushing tanks because it will screw up the valves/faucets/whatever.

A few years ago I had nothing going on a Saturday and decided to flush the radiator in an old Explorer.    I ended up wasting too much time and ended up with many buckets of coolant mixed with water to dispose.  What a pain in the ass it turned out to be.   General maintenance is good but be prepared to screw around with it when things turn south.

[GringoSalado 1652]