hot water heater question

[MtGun44]

I got 30+ years out of my first nat gas water heater, drained the lime "rocks" out of the bottom
for several years, then no more rocks, it stabilized. If I had known about replacing anodes,
it would still be running.

You have to replace the worthless plastic globe valve, which will pass zero rocks with a nice
metal ball valve to get the lime rocks out.

Bill

[KYCaster]

Like I said, it's a pet peeve of mine. When the guys working the supply houses call them one I just roll my eyes. Your acquaintance was correct in his observation. I never go as far as yelling at someone over it.

As far as cost it's relative to what your utility costs are. But as far as recovery rate it goes Oil then Gas(Natural/Propane) and then Electric. And these are directly related into how many BTUs you are firing at. Oil is putting out more BTUs then one electric element. The top element runs first and once satisfied the bottom will run. Both are not running at the same time.

I feel sorry for those on electric. 80 is the only way to have a decent recovery rate. If you have an 80 and need to replace it after April buy a smaller one and install a mixing valve on it. Run the water heater at a higher temp and mix down. A 55 gallon water heater will give you almost the same capacity as an 80 when run this way.

Dragon, I have the same peeve, but so far I've managed not to punch anybody because of it.

I disagree with your statement about the recovery rate of an 80 gal. heater vs. 50. The gallon rating on the heater refers to the amount of hot water the heater will initially supply before you start getting a cold shower and need to let it recover.

A 4500W element will provide the same number of BTU's regardless of the size of the tank it's in, so the recovery rate is actually going to be longer in the larger tank.

The purpose of the larger tank is to provide more hot water initially, like three showers in quick succession as opposed to two with the 50 gal. tank.....or filling a whirlpool tub. Still takes an hour or more to recover after your shower gets cold.

Lots of good info here.........bottom line is total cost over the life of the heater. Switching from electric to gas or vice versa can be a huge expense that will take many years to recoup.

Heating element life is almost entirely a function of water quality. The more minerals dissolved in your water, the more often you'll have problems. Mineral deposits will accumulate on the heating elements and eventually flake off. These flakes will build up in the bottom of the tank till they cover the bottom element, causing it to over heat and burn out. Draining a couple of gallons from the tank regularly does very little to alleviate the problem since the flakes are too large to go through the valve. The easiest way to remove it is with a wet/dry vac through the hole where the bottom element is screwed into the tank.

Thermostats.........no way to predict when they'll fail. They either work or they don't.

If you want to keep spare parts on hand, go to the local plumbing wholesaler (not Lowe's) and ask for a "water heater rebuild kit". You'll get two heating elements and two thermostats for about the same price as two elements.

Good luck with your water heater.....a cold shower really sux!
Jerry

[dragon813gt]

I disagree with your statement about the recovery rate of an 80 gal. heater vs. 50. The gallon rating on the heater refers to the amount of hot water the heater will initially supply before you start getting a cold shower and need to let it recover.

My comparison was for a regular 80 gallon compared to a 50 gallon w/ a mixing valve.

Gallon rating is storage size. Combine that w/ recovery rate and you know how long until you run out of hot water. Water heaters have the same recovery rate no matter the storage size. We use Bradford White, I'm not a plumber. Electrics have a 21 gallon per hour recovery rate. Natural gas fired has 43 gph while propane has 41. Even w/ gas a larger tank helps. So does a mixing valve. The less hot water you take out the quicker it recovers and less fuel/electricity it uses.

Let's say an average shower is 10 minutes at 2 gpm. You'd drain half of a 40 gallon or one quarter of a 80 gallon. When refilling w/ cold water it will mix w/ the remaining water and heat up. The mixed water will be a lot warmer in the 80 gallon compared to the 40. And while the recovery rate is fixed. The larger tank will be up to temp quicker because the water was warmer to start w/.

I did the math and for my use a 40 gallon natural gas fired w/ a mixing valve was enough. Now that the step daughter is 14 and likes showering I need to re run the numbers. Or I could just shut the hot water off when she's in there to long. You think she would have learned after the first time

[MT Gianni]

High effiency does not equate to longer life, just a higher effiency. As noted, most repairs are more costly and parts can soon be unobtainable.

[geargnasher]

I use rainwater, which Texas at least still allows me to do without going to prison like some places. Still have a well, but it redefines "HARD" water and is universally tough on water-using appliances.

BTW, Bill, thanks for commenting on the anode rod thing a couple of times, it has reminded me that it's time to pull mine out and check it.

Gear

[MtGun44]

Cheapest "fix" on a water heater is a $30 anode every 5 years or so. Just put a new
one in my sister's heater, gone at 5 years. Got about 2-3 gallons of rocks out of her
heater, pretty mild water, apparently.

Gear, how do you collect rain water and put it into service for domestic water? I have a
place in Colorado that might benefit from this.

Bill

[Petrol & Powder]

I'd bet you could forego that $30 every 5 years and still get 25 years out of a water heater; without replacing the anode.
You're still going to have to replace the tank when it rusts through and I doubt you'll get 30 years out of a tank EVEN with a new anode every 5 years.
Replace the elements when they burn out and throw the whole damn thing away when the tank starts to leak. You'll be money ahead. They are NOT made to last, they are made to be profitable. If I can buy one and use it for 25+ years, I'm still ahead of the game; in fact even at 20 years I'm OK.
The limiting factor is the integrity of the tank and I don't think that the tank will last more than 25 years, even with maintenance. It is basically a disposable unit with a 20-25 year life span, at best.

[.45Cole]

Greencountypete-
It may have been stated before in the 3 pages of replies, but I'm a little lazy. Your water quality is immensily important to how your water heater is going to work. Bad water is bad for metal, scaling, ect. A report can be had from the library usually, in the form of the yearly water report. In short, you need to assess the energy you require (as in heat of water, 150*F water plus 50*F water is 100*F for a shower, of what duration). This will give you a daily heat requirement in gallons. Doing recovery rates and such you can off hand calc what you need as far as heat goes. I would thing two heaters might be good, one gas and one electric. You will always have hot water, and you can throttle one back if it becomes too expensive. I'm in the energy calculating business and have benefited from this site. If you PM me I can help with your needs on an energy side, but not so the plumbing side.
You should see my hot water heaters, 20k+ SCFHr monsters.

[badbob454]

dont water heaters need to be flushed out or back flushed to remove calcified crud that builds up on the bottom? i heard this should be done about once every five years ..

[MaryB]

I need to find a deal on a solar preheat tank and build a hot water solar collector. It sits before the water heater and if I can raise my 45-50 degree water to 100 I save a bundle on energy costs. And with only myself a 30 gallon tank is plenty for a shower in the AM.

[MtGun44]

Petrol & Powder -
The anode rod COMPLETELY eliminates internal corrosion in the tank, it will last
forever if you don't run out of rod. Tanks are glass lined, but there are always
pinholes, and the anode rod corrodes preferentially to protect the iron. It is hard to
grasp without understanding the electrochemistry. Here is a short version; iron can't rust
if there is enough surface area of a metal that is higher on the electrochemical chart
nearby and connected physically, which aluminum, zinc and magnesium all are. External
corrosion is negligible.

I have no doubt that the tank would not corrode thru in 100 yrs if anodes replaced
regularly. The one issue is lime buildup on the inside. I wonder if it would eventually
nearly fill the tank. In any case, with anodes intact, internal corrosion is stopped.

No real need for "back flushing", but in some water conditions, NOT all, lime rocks
precipitate out and need to be washed out. The original plastic drain valves are globe
type with an internal maze structure that will only let water and rocks about 1/16" or
so thru. Must be replaced with a straight thru ball valve, which will let over 1/2" size
stuff thru. Even then you have to occasionally clear it with a metal rod. Do this
after about 1 yr and then again at 2 yr if you have lots of lime like we do in KC.
The fourth year mine had no significant new rocks. I was told that with our water,
so this may vary, once the tank is coated with lime the rocks stop building up.

Bill

[DCM]

I got 30+ years out of my first nat gas water heater, drained the lime "rocks" out of the bottom
for several years, then no more rocks, it stabilized. If I had known about replacing anodes,
it would still be running.

You have to replace the worthless plastic globe valve, which will pass zero rocks with a nice
metal ball valve to get the lime rocks out.

Bill

Big + 1 on that.

[Bad Water Bill]

I live over a HUGH limestone deposit.

When we moved in over 40 years ago heaters lasted about 3-4 years.

Being born and raised in Germany my wife said TANKLESS was the only way to go.

Well after over 35 years I replaced the first one "just because" and it must have taken me all of 15 minutes to do the job by myself.

Whats not to like about that service and I never have to remember to drain it either.

[GREENCOUNTYPETE]

an update on the water heater

I got the amp meter and tested the elements they were fine thermostats worked as they should , went to try an drain it and the drain valve is completely plugged So I figured the tank must be full of lime , well we got the new gas one and had it in the house before I disconnected the old water heater , yesterday

I had to lay the heater on it's side to drain it but got it drained , took a look down in there the anode was only about 1/2 eaten and the drop tube was laying in the bottom , so the issue all along was broken drop tube and never having been drained in 12 years the drain plugged


if some one wants it an anode and a drop tube and it would probably give many more years of service but I have already committed to the new gas water heater and looking forward to what should be a very long hot shower as soon as I get the gas run over to it

On a side note I decided even though it was really convenient to just put connectors and copper right to the water heater when I put all the copper plumbing in my house in 2006 getting rid of the old iron pipe from 1939 , I should have put unions in to be able to disconnect the water heater , I had to cut it out and this time I put Unions in

looking down in inside the water heater I was surprized how good of shape it was in and how little lime there was , but there must be an awful cake of rust at the bottom

going to flush the new one every few months and try for a long life with a much lower electric bill

[MtGun44]

Replace junk OEM drain valve with a big ball valve from home store before
installation. Drain at 6 months and then wait another year. I got a lot of rocks
first 3-4 times then no more. Seems to stabilize a lime coating after a while,
but no doubt depends a lot on water pH and mineral content.

Bill

[Bad Water Bill]

Calcium is the real culprit here.

When I moved into my home it was 16 years old and the 3/4" steel piping was so loaded with calcium the water was restricted to a trickle.

Calcium does not collect on copper so my 30 + year old tankless heater had 0 calcium buildup in it when I finally changed it out.

[GREENCOUNTYPETE]

water PH has a lot to do with lime deposit , the last town I lived in most of us in the old neighbor hood my house was built in 1873 had lead water pipes into the house , the guys with city water watch the ph very close they knew how to keep a layer of lime on the inside of those pipes and make sure they passed every lead test . most of them live just down the street and had the same lead pipes into their houses

[Petrol & Powder]

Bill, I hear you and as usual; you are absolutely correct.
The sacrificial anode does save the tank from rust and using a real drain valve will help to remove the solids that collect in the tank. If my view was totally shaped by chemistry I'd go with your method. However I must insert economics into that process and at some point we reach diminishing returns on extending the life of that electric water heater. There's no doubt that Ph, mineral content, particulates and maintenance all play a big role in the life of that tank. Even locally the water quality changes dramatically over just a few miles. I think it's a balancing act between cost of the unit, cost of operation and cost of maintenance vs. The ultimate cost over the life of the unit.

[pete501]

We are all electric and I had looked into the Heat Pump water heaters. Energy savings and a generous rebate was tempting. One of the workers at Lowes has a Heat Pump water heater in his home and had some info that was helpful in deciding against one. First the noise was such that it can be heard inside when the placement was in the garage. Second the unit produces cool exhaust making the garage a constant 38 degrees which will not work because our water heater is inside the laundry room. It might be good if you lived in a hot climate and could use the "free" air conditioning. The water heater is our largest consumer of electricity. To save money, we turn on the circuit breaker about 15 minutes before a shower. Shower every other day, wash dishes after showers. Just the two of us and wouldn't work with a larger household. We save about $20-$25 a month. Hard water here so I drain the tank and use a shop vac and a 1/2" flex hose to get all the crud out. Filters are pointless since the dissolved solids boil out into solid when heated. Water softener would help but I don't want the salt discharge in the septic tank or in the soil.

[Bad Water Bill]

"Water softener would help but I don't want the salt discharge in the septic tank or in the soil."

If a member of your family or a guest has a heart condition the softener salts MIGHT be hazardous to their health.