My Water Heater is Knocking pretty loud for the last 10-12 months... I'm trying to figure out if this is ready to die and I should replace it before it does. It's 6 years old, new with the house and it's got a 6 year guarantee.

About 6 months ago I drained it. The water was clean, but I refilled it and drained it again and I started getting this blue stuff out of it... It looked kind of like light blue crystals, different sizes but about the size of rock salt.

Someone told me the glass lining of the tank is really fiber glass and that's probably what I was seeing. If that's the case I think I want to change the water heater before it dies and leaks all over... probably on Christmas eve...

It's a 75 gallon tank with a recirculating pump, I keep the heat pretty hot so the hot water lasts longer.

Any ideas? Thanks!

nymphetamine

Honey replace that thing please and do it quickly. You have my permission.

skiberger

The crystals maybe from a detriorated dip tube. Is the circulating pump for a radiant heat system in a floor somewhere? If so, there may be air in the system when you drained the water heater and then refilled it. You may need to blead the air out.

DrDarell

The Recirculation pump is just for the hot water... The house is kind of big, so you don't need to wait for the water to get hot in the far end of the house.

speedball1

Hi Darrell,

Gas or electric water heater? Water softener? Most dip tubes I've see were white so while a dip tube could be blue a dip tube It's doubtful. I've never had the glass lining break up in a heater so I can't comment on that If your heater is gas I might have a answer for you. regards, tom

DrDarell

Hi Tom,

It's a gas water heater, no water softener... We have a pretty high chlorine content in the water, I can't drink it unfiltered... I thought this was the Chlorine from the water, I seem to remember seeing some of this stuff for pools and it looks like the same color.

I flushed the WH again today, and took some of the blue stuff and asked my sister what she thought it was, it will crumble in your fingers and she said it smelled like bleach! So I think it's the Chlorine.

I also pulled the Anode and that babys about shot so I just ordered a new one. It was coated pretty heavy with the blue stuff and some black parts... I wire brushed it pretty clean and reinstalled it. Seeing it still had some metal on it I think my tank is probably OK.

speedball1

Hey Darell,

I was betting you had a gas heater. I'm betting that you have mineral build up in the bottom of your tank that you haven't flushed out completly. I know you flush your tank but let me walk you through the procedure again.
: If you do not flush,(not drain) your heater on a regular basis it will build up mineral on the bottom of the tank. When the flame comes on it turns the water trapped under the mineral to steam and the steam escaping is the knocking that you hear. Let me show you how to flush your heater. Attach a hose to the boiler drain at the bottom of the tank. With the pressure on, open the boiler drain and let it run untill the water runs clear. You will see a spurt of red,(rust), blue(chorine) and some white grains,(lime or calcium carbonate). The whole thing shouldn't take more then a few minutes. Don't forget to flush it out every month. Your heater will thank you for it. You might want to consider cleaning the screens on your areators if you have a high mineral buildup. If thev problem still persists after you have flushed, you will have to drain the heater, remove the boiler drain and go up in the bottom of the tank with a wood or plastic rod, (not metal) and try to break up the mineral and flush it out. Good luck, Tom

DrDarell

Thanks to all, I've learned a few things I thought I'd share...
Tom's right, you need to flush your tank often, but I was having problems because of the small drain valve that came on my tank. I installed a 3/4 inch Ball Valve on the tank and you wouldn't believe all the crud that came out! (This was after flushing several times this past week.) Second I got the guts to dig through the insulation a bit to get to my anode, it was aluminum, (I say was, because it was about gone) and the Aluminum Anode is what causes the Blue stuff! I installed a new Magnesium Anode and flushed again with the new valve and for the first time in a great while my water heater is silent!
Please check out this site http://www.waterheaterrescue.com it has some great information and will get you all the parts you need to keep your water heater running happy!