Water Heater Dripping on Burner - Cracked Tank?

[clman_old]

I been working on water heaters for a lot of years but only as a sorta secondary thing. Recently an absolute certainty of whether a tank was leaking or if it was condensation dripping needed to be made. I know that it is very common for condensation to build up and drip onto the burner. And I know that sometimes it can be bad enough to put out the flame of the burner and or pilot. I also know that the position of the flue baffle can make a difference as to where the water drips. I've read that the burning process of natural gas has a moisture by-product that along with a cold portion of a tank can cause condensation and can add to the natural condensing of moisture from the combustion air in the flue.

 

Sometimes a leak is obvious - IE: Leaks on or off. Sometimes condensation is obvious - IE: Drips for awhile when a lot of cold water is in the tank, tapers off as the water heats up and eventually stops all together.

 

In the case I witnessed the dripping from was from between the portion of the flue pipe that protrudes below the tank bottom and the tank it's self in the combustion chamber. In my experience dripping from the inside of the flue pipe is condensation.

 

It is my theory that a fracture / hairline crack can retain water until heated up then expand and allow noticeable leakage. The Whirpool agent disagreed. ( It was an extended warranty job ).

 

Can anybody add their experience?

 

Thanks

[BryanS]

I'm inclined to believe a small crack can open when heated and leak. I had a Kenmore at Sears that we ended up getting replacing that would put the flame out after minutes of running. Most guys said if a crack would open it would always leak. What fix did Whirlpool provide? I could see if maybe the exhaust was blocked or something. I even removed the pipe to see if it would still get out and it did. I also blew down through the water heater to see if it was blocked. I'm pretty sure we had a tech even change the gas valve on that one. I wish I could give you a definite answer. I'm inclined to believe Whirlpool phone techs are full of crap and tend to give whatever excuse possible to not get something replaced.

[clman_old]

The first call to them resulted in the tech wanting me to do a condensation test. The second call, where I clarified that the dripping was coming from between the tank and the flue protrusion, resulted in a ra for the unit. Two days later I called the owner to find that it was still lit, coming on when turned up, blue flame with small white tips and not sizzling. I'm done with the repair because the warranty company paid off the policy as not cost effective to repair. So I can' follow up on the case. From the evidence it appears that it was just heavy condensation. I did remove the burner assmy and wipe clean the combustion air vent ( didn't remove a lot ). On this model the combustion air vent is a few rows of slots cut out of the combustion chamber floor. The slots are so fine that when water drips on them instead of dripping through, it covers them. That could of been part of the problem.

 

I personally have a Whirlpool unit and it keeps just shutting down. When I relight it, it may stay lit for a couple of days or a couple of minuets. I called Whirlpool and told them I'm a servicer, the symptoms and that I determined that the gas valve / t-stat was bad. They sent me one, asap, based on that diagnosis. Haven't changed it yet.

 

I've never had trouble with them before. Maybe I've just been lucky.