Quick basic advice on a dripping gas 40-gal hot-water heater

We *should* have done that but never did. This article says almost nobody drains their tanks nowadays:

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I don't feel too badly.

Also, Home Depot GE salespeople on the phone tried really hard to sell me the patented little fan that stirs up the sediments.

It would be nice to find an article that scientifically looks to see if those sediment stirrers really worked or not.

Consumer Reports was a total disapointment as they told me to buy based on warranty - which is a marketeer's dream. I'm surprised at Consumer Reports, but, the older (and wiser) I get, the more I realize they don't know what they're doing. Sigh.

Dan Rather, and now Consumer Reports. Another trusted icon bites the dust!

All I have left is you!

Donna

Reply to
Donna Ohl, Grady Volunteer Coo
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I pay around $1.33 per therm. I'm going to do the calculations today.

I just called Sears Kenmore (actually AO SMith State Industries makes all the Kenmore brands) asking for their highest-efficiency consumer hot water heater models.

- Sears Kenmore Home Water Heater Department: 1-800-877-6420

Here's the summary from Sears for the 40-gallon 12/1 year water heater:

- $420/$853 #33144 FHR 81 gallons, EF 0.63, BTU 40K,

- 58" tall, 20.5" diameter, 63.5" tall with diverter

Here's the summary from Sears for the 50-gallon 12/1 year water heater:

- $450/$885 #33154 FHR 97 gallons, EF 0.63, BTU 40K,

- 59.5" tall, 22" diameter, 65" tall with diverter The installation fee includes a bunch of possibly mandatory extras.

- Mandatory Installation Fee $300

- Mandatory Disposal Fee $10

- Mandatory Plumbing Permit $77

- Mandatory Flex Pipe Replacement $46

- Mandatory Sales Tax on the water heater ~8.75%

- Possible Earthquake Straps $68

- Possible pipe retrofit fees ~100

- Possible trip charge of $35 to $80 if any service is refused

I still have to do the calculations to see if the EF makes any real difference at a cost per therm of $1.33 particularly since the "average" water heater at HD was 0.58 or 0.59 EF, but I could special order a HD one with 0.62 EF but I could get from Sears one with an EF of 0.63.

I wonder how much exactly it all matters ... for that ... I need to build the calculations.

I think I have enough now - certainly more than I ever thought I needed to know - to make a reasonable not-dumb decision on replacing my home water heater that started leaking yesterday morning.

Please let me know if you have any calculators on the web which can COMPARE two home water heaters given the specs we have posted in this thread!

Thanks, Donna

Reply to
Donna Ohl, Grady Volunteer Coo

Hi Malcolm,

I did more research. Apparently, all GE water heaters sold by HD are made by Rheem who also makes a water heater with an EF of 0.62 but it's hard to find in a HD store. I'm gonna try Sears at 800-877-6420.

$360 ($675 installed) GG40T06TVG/182-785 FHR=68 gal EF=0.62 40,000 BTUs The nearly meaningless specs are 40-gallon capacity & 6-year warranty.

$420 ($730 installed) GG50T06TVG/184-045 FHR=83 gal EF=0.62 40,000 BTUs The nearly meaningless specs are 50-gallon capacity & 6-year warranty.

I am trying to figure out the calculation for the payback time given the difference between an EF of 0.59 and the EF of 0.62.

Do you think it's worth it to pay (how much) more and go to more trouble to find a residential gas hot water heater with the EF of 0.62 (given my current cost per therm of $1.33)?

Donna PS I'm gonna try the math for FHR & ER payback calculations here

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Reply to
Donna Ohl, Grady Volunteer Coo

Hi Franklin,

Thanks for asking for help. I did some research just for you and I think the closest I can find to help you in a freeware section (since you are so well known from the freeware side) is the GAMA Association of Applicance Manufacturers web site - open and available to all.

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At that site, they provide links for both supplier and consumer bill-of-material and inventory calculators, mostly for suppliers who wish to design and deliver inventory to commercial and consumer.

For example, here's their section on product certification:

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Here is their section on government affairs:
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And, Franklin, here is their section on public information:
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I've run a few more searches for you and this is the best they have that I can find to help you but I will try to see if I can write a PERL program that does the FHV and ER calculations I need.

You can rest assured Franklin that I will post the results (if successful and meaningful) back to the group but first, I'm asking the experts who know much more than I do about the implications of the FHR and EF ratings because I want the program to be correct. Don't you think that prudent?

As you know, I always help everyone I can and I always give back more than ask for, and I summarize in the end so a newbie starts off where we left ... so, you can rest assured, at least on the water heater topic, that I will provide full telephone numbers, part numbers, product specifications, prices installed, gotchas (like mandatory replacement of flex pipes and $77 plumber's inspection fees) and the like.

What else do you need Franklin?

Donna

Reply to
Donna Ohl, Grady Volunteer Coo

A HWT tank explosion requires at least two things - the thermstat sticks on, the overpressure valve seizes shut (and likely that you have a non-return valve in the supply). A leak implies none of these.

An explosion is nothing to joke about. It _can_ completely demolish a house. But that's _not_ a concern with a simple leak.

The hazard with a leak is that the leak may abruptly get bigger and dump a lot more water a lot faster. It's probably not going to do this any time soon, but you never know. So, don't leave it long. You could turn off the inlet supply valve if you're away for any protracted periods.

Reply to
Chris Lewis

I wouldn't suggest that worry unless there is some problem with the existing galvanized pipes. They last many, many years many places.

Reply to
Bob F

If you plan on flushing the tank and inspecting the anode annually from here on out, I would expect that the higher efficiency model will be your better buy unless the price is *significantly* higher. Proper maintenance could make the tank last 30 years or more, it's just that few people actually do it.

I write the flush/inspection dates right on the side of the tank in Sharpie, that reminds me when it's time to do it again.

nate

Reply to
N8N

lets assume a 300 buck a year operating cost and it sounds like you might save 4% on a more efficent model.

4% of $300 is $12 bucks a year, thats no biggie.

now the 90+ tanks might cut your water heating bill by nearly half, but purchase cost will be a lot more

Reply to
hallerb

True, but there's one minor complication: the larger tank will probably have a smaller ratio of surface area to volume[1]. Since surface area is basically what determines the rate of heat loss[2], a tank that's double the size will not lose heat at double the rate.

So while the larger tank will lose more heat, the increase in lost heat is smaller than linear.

On the other hand, having a water heater with a large capacity can encourage people to take excessively-long showers if they are already inclined in that direction, and having a water heater with a small capacity can definitely discourage long showers. :-)

- Logan

[1] As a starting point for visualizing this, imagine a 100-gallon water heater as simply two 50-gallons stacked on top of each other. When you stack them, the bottom of the upper one and the top of the lower one will be up against each other and thus not losing heat from that surface. So you've eliminated some surface area. Real water heaters will have different proportions, but the same basic idea applies. If you model them as spheres, volume is proportional to the cube of the radius but surface area is proportional to the square. [2] ... along with temperature difference, but that's a constant here, so we can eliminate it from this comparison.
Reply to
Logan Shaw

"Donna Ohl, Grady Volunteer Coordinator" wrote in message

Do you get a choice of KY or Vaseline too?

Call al local plumber and save a bundle of money. The flex pipe should be replaced with every installation though.

Reply to
Edwin Pawlowski

n

or a local handyman, tanks are easy to change, few DIYers get permits

Reply to
hallerb

Doing this can cause drips at the safety valve, since water expands when heated, and the inlet pipe may be the direction the pressure thus developed is normally relieved.

Reply to
Bob F

n

What on that list is so excessive or wouldn't incur a similar charge from a local plumber? They all seem within reason, depending of course on the area.

Reply to
trader4

The total is in the $680 range for most options. Start with he basic $300 charge. Double what a local guy may charge. Permits can very , but probably closer to $25 if you actually get one. I'd not get one. What about that $80 trip charge? Sears will hose you no matter what. Last place I'd go.

Reply to
Edwin Pawlowski

Install 300 Disposal 10 Permit 77 Flex Pipe 46

That's $433 plus tax for a straightforward typical job. You may be able to get it done for less, but it's not an outrageous price either.

=A0Start with he basic $300

$300 is a typical price here in NJ.

=A0Permits can very , but probably

Any decent licensed plumber is going to get a permit, if one is required. It's not a customer option, either you need one or you don't. Now $77 may be a bit high, but with the way all kinds of fees and permit charges have been jacked up here and in many other parts of the country, it wouldn't surprise me to find that it could cost that much. How about the plumber's time in going and getting it?

What about that $80

What $80 trip charge? That was IF SERVICE IS REFUSED. Meaning they make a wasted trip and are locked out, etc.

Reply to
trader4

place I'd go.

sears charges a trip charge for travel.

as a matter of fact if you get your furnance with air serviced they charge a trip charge twice, then discount the second trip charge by half.........

sears is a rip off that deserves to go into the dustbin of retail history

Reply to
hallerb

in

It's been better than a couple of decades since I bought a new water heater, and that one was electric, but...

the installation fee seems high - enough to double the cost of the appliance. sales tax on the heater? - I seem to remember that something that becomes part of real property is sales tax exempt, if you file the proper certificate, in NJ anyway earthquake straps?

The one time I had to replace the water heater, I bought it from Sears - the installed price was better than an independent plumber, the service was fast (called in the morning, heater was in that afternoon) and the installer was pleasant and informative. A lot can change in 20+ years, but if/when I again need a new heater, I'll at least see what they have to say.

Also, all the back and forth about the relative cost of operating a smaller heater compared to a larger one seems to me to be fairly easily resolved - take a look at the energy guide label. When I pick a 30 gallon heater and a

50 gallon heater at random and compare the estimated annual operating cost, the difference is $7.00 a year in favor of the smaller heater. Your actual operating costs will depend on the cost of fuel in your area and your actual usage, but while I don't advocate getting a larger heater than you need, the annual operating cost difference doesn't seem like a reason to get something smaller than you could use.
Reply to
Lou

You must get a plumbing permit in my town: Home Depot charges $77 Lowes charges almost $90 Sears charges $95 for that same permit.

The overall installation fee (includes all sans tax & straps) is: $400 Home Depot 877-467-0542 $410 Lowes 877-465-6937 $433 Sears 800-877-6420

What would a typical plumber have charged for the permit and installation?

Donna

Reply to
Donna Ohl, Grady Volunteer Coo

It turns out a lot of people were dead wrong on efficiency, including me. According to the

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web site, operating a 40-gallon hot-water heater is no more or less efficient than operating a 50-gallon hot-water heater.

The only thing that matters for efficiency is the Energy Factor (EF) which takes into account the tank size, insulation, and burner BTU. Reference site:

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So, if a 40 gallon hot-water heater has an EF of, say, 0.63 while a

50-gallon hot-water heater has an equal EF of 0.63, then the costs are EXACTLY the same to operate the two heaters!

The math is all spelled out for us in the PDF at:

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$FILE/12-07-gas-rwh.pdf Since almost all of us were dead wrong on this one, it would be nice if someone can read that reference document and let me know if my new conclusions that size doesn't matter has any flaws in it as I publically state that all that matters is the EF (based on my reading ten times of that document).

Donna

Reply to
Donna Ohl, Grady Volunteer Coo

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$FILE/12-07-gas-rwh.pdf>

PLEASE DOUBLECHECK THESE HOT-WATER-HEATER CALCULATIONS!

Here are the necessary calculations I believe we need to make in order to compare two gas-fired water heaters. All calculations are courtesy of the referenced PDF and charts at

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except the energy costs which are courtesy of PG&E at
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In reality, these calculations would need to be done for at least a half-dozen different water heaters (two each from Lowes, Sears, and Home Depot, for example) in order to properly choose an available water heater intelligently.

For simplicity, I'll use the values I plugged into the calculations for my home; yours may differ but the mathematical approach is exactly the same.

  1. Calculate minimum legal efficiency (EF)
  2. Calculate maximum peak-hour requirements (FHR)
  3. Calculate total installed price ($/installation)
  4. Calculate yearly operating costs ($/year)
  5. Calculate payback period (months/installation)

Here are my calculations. PLEASE CHECK FOR ERRORS OR OMISSIONS AS WE ALL ARE LEARNING FROM THIS!

  1. Calculate the minimum energy factor required by federal & local law: (based on October 1990 Dept. of Energy Test Procedure for Water Heaters as published in the May 11, 1998 Federal Register.)

For gas-fired residential water heaters, the minimum energy factor is: Minimum EF for 40-gallon water heaters = 0.67 - 0.0019 * 40 = 0.58 Minimum EF for 50-gallon water heaters = 0.67 - 0.0019 * 50 = 0.59

Note: Southern California uses different legal minimum numbers than northern California so be advised to modify the calculation for your area!

  1. Determine your peak requirements:
20 gallons per shower x 2 showers in one hour = 40 gallons per hour 20 gallons per bath x 0 baths in one hour = 0 gallons per hour 2 gallons per shave x 0 shaves in that hour = 0 additional gallons 4 gallons per personal wash x 0 = 0 additional gallons 4 gallons per shampoo x 0 = 0 additional gallons (do it in the shower) 4 gallons per hand dishwashing x 0 dishes = 0 gallons 14 gallons per dishwasher load x 1 load = 14 additional peak gallons 5 gallons per food preparation x 1 meal = 5 additional gallons 26 gallons per wringer wash x 1 load = 26 additional peak gallons 32 gallons per automatic wash x 0 loads = 0 additional peak gallons

----- TOTAL PEAK GALLONS = 40 + 14 + 5 + 26 = 85 gallons First Hour Rating

  1. Determine price installed (inclusive): Sears 33154 is 2 (9 for the heater + 3 for full installation) HD 183-717 is 7 (9 for the heater + 8 for full installation)
  2. Determine yearly operating costs given your basal energy unit, FHR, EF, and average-use assumption.

For simplification, I'll only compare two heaters but the calculator we create needs to cover at least a few at a time. I did this in Excel for current northern California baseline (Schedule G-1 Residential Service) energy rates.

CHOICE A: Sears 33154 (marketed as Kenmore but made by AO Smith) FHR=97 EF=0.63 (41,045 btu/0.63)($1.21106/therm * 1 therm/100,000 btu) x 365 = $288/year

CHOICE B: Home Depot 183-717 (marketed as GE but made by Rheem) FHR=80 EF=0.58 (41,045 btu/0.58)($1.21106/therm * 1 therm/100,000 btu) x 365 = $313/year

Note: Irrelevant specs would have been tank size, burner BTUs, gallons to recovery to 90 degrees in one hour, etc. as the only figures that matter for the calculations are the EF and the FHR since they take into account all other design-size specifications such as those you quoted.)

  1. Determine payback period: a. Additional cost of more efficient model = 2 - 7 = 5 b. Annual savings of more efficient model = 3 - 8 = per year c. Payback period = 5 / * 365 / 30 = 65 months (5.4 years)
  2. Determine overall savings: The two water heaters compared in this simplified calcuation would be equivalent in overall costs at approximately 5 and a half years.

Considering the average water heater lasts 13 years, total savings for the more expensive yet more economical heater would be:

(13 years - 5.4 years) * $25/year = $190 savings overall

  1. Choose the correct water heater:

Based on the math everyone should perform when selecting the proper water heater, I would buy the Sears 33154, which will save me almost 200 dollars over its lifetime over the Home Depot 183-717 assuming current energy prices and average usage.

Note: In reality, one needs to compare at least a half-dozen water heaters; here I only compared two for simplicity. I knew none of these calculations just two days ago, so, PLEASE CHECK MY NUMBERS after reading the reference document I refer to.

If the numbers hold water, then this should go into the alt.home.repair FAQ for everyone to benefit from all our efforts to understand how to properly size & select a home water heater replacement (yes, I know there are physical size issues also but this tutorial is already too long to go into those details).

Donna

Reply to
Donna Ohl, Grady Volunteer Coo

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