In a previous answer, you said to shut off the water main. Does that mean water to the entire house or the main line to the water heater? Also, I have been looking into having an auto shutoff panel installed to automatically shut off the water and gas in the case of a leak. This is very expensive. Is it worth it?

Hi Bh

You can shut off the water main every time you leave the house or you can install an automatic shutoff... seems worth whatever the cost needed too me! This auto. Shutoff should be installed on the main water supply to the house, if possible, and in this way you protect the whole house... not just the water heater!

Back at you...

Mark

Thanks MASS for your reply. The shut off control panel would be tied directly to the hwh and not to the main water valve.
Another question. If the hwh rusts out and leaks from the bottom, wouldn't the basement still flood with existing water in the tank, possibly damaging the basement area? Is there a suggestion to contain some 40 gals. Of water escaping?

First, if you were to use something like the LEAK-GUARDIAN (RF transmitter) then you could have it on the water main and just use a few different transmitters in areas of concern (like washing machine, hot water heater, boiler, etc... ) and in this way protect your whole house quite well... ;)

Check out the leak-guardian here:

http://www.petro-meter.com/pdfs/Leak-Guardian.pdf

The only problem with the leak-guardian is that it doesn't shut off the gas.

__________________________________________________ __________

Otherwise, if you plan on installing the shut-off at the water heater (one that shuts gas, too) you have to understand that in most cases, when the leak is detected and the water shuts off automatically the water heater will NOT drain out completely. Here, the water heater will depressurize, but the majority of the water will stay in tank via the vacuum created within the CLOSED SYSTEM. If someone opens a faucet that vacuum would be lost and the heater would start to drain some.

Note also, that most leaks don't occur at the bottom of the water heater. Most leaks, in my experience, occur near the top, so unless there is a catastrophic failure (vessel bursts) you should not have to worry about the water heater emptying completely.

That make sense?

First, if you were to use something like the LEAK-GUARDIAN (RF transmitter) then you could have it on the water main and just use a few different transmitters in areas of concern (like washing machine, hot water heater, boiler, etc...) and in this way protect your whole house quite well...;)

Check out the leak-guardian here:

http://www.petro-meter.com/pdfs/Leak-Guardian.pdf

The only problem with the leak-guardian is that it doesn't shut off the gas.

__________________________________________________ __________

Otherwise, if you plan on installing the shut-off at the water heater (one that shuts gas, too) you have to understand that in most cases, when the leak is detected and the water shuts off automatically the water heater will NOT drain out completely. Here, the water heater will depressurize, but the majority of the water will stay in tank via the vacuum created within the CLOSED SYSTEM. If someone opens a faucet that vacuum would be lost and the heater would start to drain some.

Note also, that most leaks don't occur at the bottom of the water heater. Most leaks, in my experience, occur near the top, so unless there is a catastrophic failure (vessel bursts) you should not have to worry about the water heater emptying completely.

That make sense?

Hi MASS,

Thanks so much for the info. I will probably just go with a water alert alarm which will be put near the hwh. If I get an alert, will shutting off the water main and the "cold" lever manually on the hwh create the vacuum you described? I would also turn the gas gauge to "pilot".

When we go on vacation, I will turn off the water main and set the gas gauge to "pilot". Will turning off the water main affect the sprinkler system outside?

Here is what happened to us in Oct. The hwh definitely burst since the water was coming out of the bottom. Since it happened during the night, my carpets were totally saturated by the time I discovered it. We have a water softener system and the plumber said that this will deteriorate the hwh. I know now to drain the tank once a year and replace the anode every 2 years. The hwh was only 6-1/2 years old!

Thanks again for your professional feedback.