I know this is a long shot, but maybe I'll get lucky. I have water leak at or near my Atwood GE16 EXT water heater. The floor in the bay gets wet at the front lower left corner as you are looking at the heater from the outside. The heater is mounted on a wood platform which remains dry as far as I can see. All water lines to and from the tank as far as I can see and feel have no visible leaks. The water pressure relief valve has no visible leaks and is fairly new. The water on the floor is cold so I don't think the tank itself is leaking as this thing makes very hot water. Any idea about what I may be missing? Thank you for any help.

Any chance that rain water is getting in there?

You said the unit was new and makes hot water but the water under the tank is cold that sounds like a leak in the cold water line coming into the WH. Put a piece of toilet paper under the fitting or just wipe the fitting and see if the paper is wet. Make sure its not rain water as someone else said. I doubt that your tank is leaking.

Not rain water, it started way before hurricane Harvey. The unit is not new, it's a 2008. I said the pressure relief valve was fairly new. All water lines I can see and reach are dry. The raised wood platform under the heater is dry, but the floor is wet next to the platform and the wall of the water heater enclosure.

To isolate if your leak is in the pressure side of plumbing or another type of leak...Do the same test OEM are supposed to do. An air pressure test (best in my opinion), if gauge loses pressure with when in 10 min, you have a leak on the "pressure" side. If it holds pressure...pressure side is OK and look for another cause.

I believe that WH has an external mixing valve (mine does). It has a cold water connection you might check for a leak.

Water Heater Issue | Good Sam Community

12 Replies

Sooner_Schooner
Explorer
Sep 01, 2017
dougrainer wrote:
The ONLY sure way to verify if water heater or other source is to disconnect the Cold input and the Hot output and connect the 2 together. DRAIN the water heater and then test. IF you get the same water, it is not the water heater. IF you DO NOT, then the odds are the Aluminum tank of the water heater has a pinhole leak in the tank. You do not state how old the water heater is. But, corrosion can happen in less than a year on a Aluminum tank depending on the type water that was in the tank. Doug

It's the original water heater and the water on the floor is always cold, and this water heater is very hot.
dougrainer
Nomad
Aug 31, 2017
The ONLY sure way to verify if water heater or other source is to disconnect the Cold input and the Hot output and connect the 2 together. DRAIN the water heater and then test. IF you get the same water, it is not the water heater. IF you DO NOT, then the odds are the Aluminum tank of the water heater has a pinhole leak in the tank. You do not state how old the water heater is. But, corrosion can happen in less than a year on a Aluminum tank depending on the type water that was in the tank. Doug
Old-Biscuit
Explorer III
Aug 31, 2017
uncle t wrote:
i had a similar problem. turned out the pressure relief valve "burped " every now and then.

T&P Relief valves do NOT 'Burp' .....they OPEN at 210*F/150 PSI

They might 'weep' due to loss of air pocket at top of tank
But water dripping from T&P would collect in water heater draw pan.

OP...
What is above/to the left of that bay?
Left of the water heater is the bay with black and grey tanks, and water/sewer hookups.
All water lines for the coach run in that bay and ALL are dry as far as I can see. This is mind boggling and puzzling.

I would be investigating those items more closely.
Especially items that are close to that wall
uncle_t
Explorer
Aug 31, 2017
i had a similar problem. turned out the pressure relief valve "burped " every now and then.
Sooner_Schooner
Explorer
Aug 31, 2017
Old-Biscuit wrote:
Wood platform DRY

All fittings/connections on TANK if leaking would run down onto wood platform

Floor NEXT to WH and WALL are wet

What is above/to the left of that bay?
Left of the water heater is the bay with black and grey tanks, and water/sewer hookups.All
water lines for the coach run in that bay and ALL are dry as far as I can see. This is mind boggling and puzzling.

Atwood GE16-EXT
Mixing Valve screws into HOT out on tank
Cold Inlet at bottom with a 'cold tempering line to Mixing Valve
Old-Biscuit
Explorer III
Aug 30, 2017
Wood platform DRY

All fittings/connections on TANK if leaking would run down onto wood platform

Floor NEXT to WH and WALL are wet

What is above/to the left of that bay?

Atwood GE16-EXT
Mixing Valve screws into HOT out on tank
Cold Inlet at bottom with a 'cold tempering line to Mixing Valve
Kayteg1
Explorer II
Aug 30, 2017
With today's technology almost everyone has phone camera that will fit in impossible (in the past) places and take good pictures of stuff you can never see with bare eye.
Why not take advantage of it?
janstey58
Explorer
Aug 30, 2017
I believe that WH has an external mixing valve (mine does). It has a cold water connection you might check for a leak.
path1
Explorer
Aug 30, 2017
To isolate if your leak is in the pressure side of plumbing or another type of leak...

Do the same test OEM are supposed to do. An air pressure test (best in my opinion), if gauge loses pressure with when in 10 min, you have a leak on the "pressure" side.

If it holds pressure...pressure side is OK and look for another cause.
Sooner_Schooner
Explorer
Aug 30, 2017
Not rain water, it started way before hurricane Harvey. The unit is not new, it's a 2008. I said the pressure relief valve was fairly new. All water lines I can see and reach are dry. The raised wood platform under the heater is dry, but the floor is wet next to the platform and the wall of the water heater enclosure.