New Hot Water tank Leak or Condensation? AO Smith GCV 50 300 ProMax

**Jim99** · 03-31-2012, 11:45 AM

Hi,

I had an AO Smith GCV 50 300 ProMax 50 gal gas water heater installed last weekend. There appears to be a minor leak under the bottom lip on the back side of the tank opposite the burner. Plumber returned mid week and explained it was condensation between the inner tank and the insulation and would disappear over the next several weeks. The leak appears to be less now, maybe 1 oz or less per day. Is this normal?

Thanks in advance for your advice.

**Hackney plumbing** · 03-31-2012, 11:55 AM

Water heaters do condensate at times.

**Jim99** · 03-31-2012, 12:03 PM

Thanks Hackney,
When you say condensate are you referring to the Flue condensate from the burner gas or condensation on the exterior of the inner water tank?
Is this going to rust out my tank prematurely?

**Hackney plumbing** · 03-31-2012, 12:37 PM

I'm referring to condensate...take your pick as both apply in your case. It can cause a tank to fail prematurely. I'm not saying yours will. You can read about it in your owners manual.

**jadnashua** · 03-31-2012, 04:41 PM

The more you drain the WH, the more the cold water in the tank can cause condensation. Also, when the burner first turns on when the tank is cold, the moisture produced when the gas is burned can condense. Once things get hot enough, it stays as vapor all the way out the flue. If the flue isn't adequate, you might be getting some spillover, too. One good test is with a smoking candle or cigarrette - see if the smoke is sucked up the flue while the burner is on. If it is lazy or backdrafts, you need to address that.

hj · 03-31-2012, 06:33 PM

Condensation occurs when moist air contacts a cool surface, which is below the dew point for the amount of moisture in the air. The only place condensation should occur in a water heater is in the flue when the heater is initially filled with cold water. The combustion gases will condense water which will drip on to the burner causing a "sizzling" sound. After that, the water entering the heater will be partially heated on its way to the bottom of the heater, so it should never cause condensation. Besides that, the insulation around the tank will keep any moist air away from the tank. One property of a small leak in a metal tank is that it can "rust over" and stop, at least until the rust spot gets larger. I have removed the insulation from many tanks which failed because of leakage, and some looked like they were shot with a machine gun because there are so many "old" rust spots on them.

**Jim99** · 04-10-2012, 02:43 PM

Originally Posted by Jim99

Hi,

I had an AO Smith GCV 50 300 ProMax 50 gal gas water heater installed last weekend. There appears to be a minor leak under the bottom lip on the back side of the tank opposite the burner. Plumber returned mid week and explained it was condensation between the inner tank and the insulation and would disappear over the next several weeks. The leak appears to be less now, maybe 1 oz or less per day. Is this normal?

Thanks in advance for your advice.

Update:

We left home for a week, before leaving we shut off water to tank, shut off burner and gas. When we returned today, no water under the tank.
Fired up the heater and now we will see if it any water leaks. The water heater is in the same small room as the furnace and was a constant 66 degrees.
If the initial problem was condensation we shouldn't see any more leaking as the 50 gals in the tank was at room temp when fired up today.

**Jim99** · 04-11-2012, 03:37 AM

Tank is leaking again. It appears having water pressure and hot water in the tank resulted in the leak starting again.

**Runs with bison** · 04-11-2012, 08:54 PM

Originally Posted by Jim99

Tank is leaking again. It appears having water pressure and hot water in the tank resulted in the leak starting again.

Sounds like the tank has a pinhole leak. It needs to go back under warranty. Plumber needs some pressure from you to to take care of the issue. Others will correct me if I am mistaken, but the plumber probably doesn't get a dime from the manufacturer for tearing out the defective tank and replacing it, so to him having to do so is lost time & money. (Car dealerships are different...they like warranty work as they get paid directly from manufacturer for labor...in slack times they get all happy when you find some obscure recall that applies to your VIN#.)

Stuff like this happens. (I even got a defective/deformed toilet tank from Toto that I took back to the supply house for another...this sort of defect in a Toto is apparently extremely rare.)

**Jim99** · 04-12-2012, 06:27 PM

Plumber replaced the water heater today, insisted on $185 labor charge.. No leaks on new tank.

I have emailed AO Smith for a refund of the labor charge. I can't blame the plumber the AO Smith Tank was defective and leaked from the get go 18 days ago.

**Hackney plumbing** · 04-12-2012, 06:33 PM

The way I see it if the plumber supplied the water heater then you shouldn't have had to pay a labor charge. He should have billed A.O. Smith or the supply house. Unless he specified otherwise before the initital installation.

I give a year from top to bottom warranty that the heater operates properly or I repair or replace it free. Thats just me tho.