Longevity of Conventional Water Heater Tanks.

[lagudo]

I have just finished watching on NACHI TV "How To Inspect A Tankless Water Heater" Great information and I recommend that everyone watch though I must say that it is a long episode. Over an Hour.

One issue that struck me and I did not realize is that because of the new energy efficiency standards any conventional water heater tank built after 2004 has a life expectancy of 3-5 years. This is because the walls of the tank are thinner and prone to bursting. All this to increase energy efficiency by 1.5%. At least this is what was said on the show from an installer of tankless water heaters. is this true or close to the truth.

Does this mean that the home I inspected yesterday for a buyer with the water heater replaced in 2006, I should put in my report the issue of the new standards of water heater tanks and recommend that monies should be budgeted for future replacement because of the life expectancy. Or for that matter state that the 4 year old water heater is at the end of it's expected life and replacement would be warranted before the seam splits and floods the home. It was also stated that a pan with drain would not help if this is the case. Older water heaters usually fail at the bottom, hopefully draining into a pan and out the drain. A seam split with the water pressure build up would go everywhere.

Any thoughts on this? What do some of our members have to say about this?

[James H. Bushart]

Originally Posted by lagudo

I have just finished watching on NACHI TV "How To Inspect A Tankless Water Heater" Great information and I recommend that everyone watch though I must say that it is a long episode. Over an Hour.

One issue that struck me and I did not realize is that because of the new energy efficiency standards any conventional water heater tank built after 2004 has a life expectancy of 3-5 years. This is because the walls of the tank are thinner and prone to bursting. All this to increase energy efficiency by 1.5%. At least this is what was said on the show from an installer of tankless water heaters. is this true or close to the truth.

Does this mean that the home I inspected yesterday for a buyer with the water heater replaced in 2006, I should put in my report the issue of the new standards of water heater tanks and recommend that monies should be budgeted for future replacement because of the life expectancy. Or for that matter state that the 4 year old water heater is at the end of it's expected life and replacement would be warranted before the seam splits and floods the home. It was also stated that a pan with drain would not help if this is the case. Older water heaters usually fail at the bottom, hopefully draining into a pan and out the drain. A seam split with the water pressure build up would go everywhere.

Any thoughts on this? What do some of our members have to say about this?

Personally, I don't understand how anyone can calculate -- in advance -- an "average" life span. Do they cite a source or pull this out of the air?

I think that our video producers have made themselves experts in a field that does not yet exist...that is "psychic home inspecting".

To determine an 'average" life span we will need to evaluate over time how long these new heaters last. Perhaps, from an engineering standpoint, the thickness of the wall does not directly relate to its ability to withstand heating/cooling effects over a period of time.

Be careful about telling your client that their relatively new water heater installed in 2004 is scheduled to throw craps in two more months...just because a NACHI Tv video told you.

[lagudo]

I agree James. It would be nice to see some concrete data on this. But for the sake of arguement, say this is true. Who thought up of this idea to save 1.5 % in energy efficiency on a water heater that may only last 5 years or is this propoganda from the tankless water heater companies to promote there product. Have they been lobbying the government to change so people will see the value of tankless. Maybe it's a conspiracy. LOL Nothing surpises me so you never know.

[Jack L. Gilleland]

Most of the water heater (tank type) manufactures have 5 an 10 year (and some 15 year) warranties that can be purchased even with the bottom of the line heater (State Heaters start at 6 years). You can look others up yourself I believe you'll find all the top brands are very similar.
His info was quite good on the tankless, but maybe jaded on tank type.

[Marc D. Shunk]

Be advised that electric water heaters were not part of this "thinning" requirement. It only applied to gas fired tank-type water heaters.

[jkogel]

Originally Posted by Marc D. Shunk

Be advised that electric water heaters were not part of this "thinning" requirement. It only applied to gas fired tank-type water heaters.

That makes sense. A thinner Electric tank would be less efficient due to heat loss.

[Larry D. Kage]

Originally Posted by Marc D. Shunk

Be advised that electric water heaters were not part of this "thinning" requirement. It only applied to gas fired tank-type water heaters.

Source please? I would enjoy reading about this. Thanks.

[Marc D. Shunk]

Originally Posted by lkage

Source please? I would enjoy reading about this. Thanks.

Electric water heaters do not feature a heat exchanger. Simple as that. There would be -zero- benefit to thinning anything on an electric water heater. It is the heat exchanger that may potentially be thinned on gas fired water heaters, to aid in more rapid heat transfer.

[Marc D. Shunk]

You may not actually find any water heaters that were ever manufactured with thinned heat exchangers anyhow. This is only one method to meet EPAct requirements. Other possible methods include:
• heat traps
• plastic tank
• increased jacket insulation
• insulated tank bottom (electric only)
• improved flue baffle/forced draft
• increased heat exchanger surface area
• flue damper (electromechanical)
• side arm heater
• electronic (or interrupted) ignition
• heat pumps

Manufacturers, such as Rinnai, are using the possibility of thinned heat exchangers as part of their marketing pitch to cause the payback on their equipment to make sense. Do a payback analysis yourself, and you will see beyond a shadow of a doubt that tankless water heaters seldom make financial sense.