Water heater leak water source? See photos.

[Gene South]

This water heater was manufactured in 2003, the same year the house was built. With the similar date and the look of the installation, it isappears original to the home. The waterheater was functioning and the pan was dry with no leaks.

Notice however the water pan has a rusted water line of approximately1 ½ inches indicating the pan has held water for a period long enough to leavea permanent rust mark on the pan.

Assuming the water heater is original, and is not leaking now,what can you guess about the origin of the original water? The TPR valve had a rust stain, so my guessis the TPR valve fitting leaked at one time, but was since repaired or replacedand now the pan is dry.

Sound plausible or likely? If not, what is your guess on the source of this amount of water?

See the photos.

[Dom D'Agostino]

That last photo clearly shows a leak.

Was it enough to fill the pan? Can't say. I don't see any water rings on the heater's outer shell.

Where does the TPR extension go? Is it connected to the same drain line that serves the safety pan? May be the valve was discharging, and it backed up into the pan.

[Gene South]

The TPR was piped and discharged to the exterior.

[Jack Feldmann]

If there isn't an active leak now - everything else is just a guess.
Like you said, there was a leak at the TPR, but I assume its not leaking now.

I don't really spend much time trying to figure out what leaked and when if there isn't a leak now.

[Bob Harper]

CSST bonding?
Shutoff?
Sediment trap?
Pan drainage?
Support for TPR discharge?
TPR discharge point visible and cannot freeze up?
Corrosion on TPR discharge tube elbows?
Tortuous TPR discharge pathway?
Strap WH so cannot fall over?
Attic framing beefed up to support or spread load?
Is that B-vent with a draft hood connector directly to the draft hood?
Min 5 ft vertical venting?

Moisture/ stains in pan could be from flue condensation, sweating water pipes, leak around TPR or tank leaks.

[H.G. Watson, Sr.]

Freezing snap, ice storm, one of those rare snow events, no heat, frozen cold inlet valve or pex fitting to same, or condensation from vent/connector is my guess.

Can't see clearly, but what's going on at the top at the cold inlet stop and white (mineral) streaking on the pipe insulation at the top of the WH? What did you see at the top of the WH? Signs of Pex to valve, or Valve stem leaking possibly started during a sustained cold/freezing episode earlier? staining at the top? Is that light streak on the pipe insulation signs of water & mineral deposits dripping, running onto top?

Never made sense to me having a storage type WH and plumbing above the insulation in cold attic when it obviously sometimes (albeit rarely) has sustained below freezing temps, even DFW and So. IIRC there's been a a few periods since 03.

The burner grille plate is not in correct position. Looking at the second photo opening looks like rust collection between outer and insulation.

discharge line no slope along floor joists, some discoloration and streaking might be there as well at fitting, may have been replaced following tube freezing.

Remove plate and investigate burner and area below for signs of WH sitting in water, burner and plate likely just above the water line.

[Nolan Kienitz]

Per manufacturer the TPRVs are to be replaced every 3-years and tested annually.

Granted no one ever does such, but I just relay what the two manufacturer's of the TPRVs say.

.

[Bob Knauff]

May have been the result of a leak at a pipe fitting on top of the unit or a leaking shut off valve? The water ran on top of the heater and into the casing around the pipe or sacrificial rod entrances, down the tank/insulation, followed the top of the TPR fitting out the hole in the case?

Repair of the fitting leak(s) leaves dry pan.

[Eric Barker]

As a general rule Gene I don't care where the leak is/was from - too easy to be wrong. As far as I'm concerned my job is to raise a question for the buyer to pursue with the seller. Perhaps the leak was repaired or maybe it wasn't - I don't assume either way.

[Jim Luttrall]

Gene, one thing for sure is that water runs down hill.
I think I see mineral deposits at the cold water valve.
I also often see leaks that migrate down to the heater from a improper storm collar on the vent pipe.
Once the water is on the top of the heater, it will run out of every opening, including the TPR hole; so that stain may be a red herring.

[Gene South]

Hi Jim, Good observation. Thanks.

[Darrel Hood]

Frequently in new construction, circumstances lead to installation of attic water heaters before the roof is completely dried in. The result can be rain water in the pan until it evaporates after several weeks or months. There appear to be other causes in this example but just for future reference.