Gas water heater capacity

I need to replace my 50 Gal. gas water heater. I've been living alone in a house and never run out of hot water. I always take showers, never baths, and my overall hot water use is exceptionally low.

I'm wondering about two things. Would a 40 Gal. tank meet my needs and would I realize a noticeable savings by going with a smaller tank?

BTW, I rent the tank.

Thanks!

Reply to
RepairNovice
Loading thread data ...

You mean by a 40 gallon gas heater? Or a 40 gallon electric heater? If comparing electric versus gas do a cost comparison of the two fuels, for your area. =2E As long as it provides sufficient hot water each time you use it is doubtful that you would save very much, if anything noticeabl;e by installing a smaller tank. the amount of heat lost from a well insulated tank/heater being very small. Note:

Also the heat 'lost' from the heater helps, in winter anyway, to warm the house!

Note. The difference in surface area of a 40 gallon compared to a 50 gallon tank will be approx. of the order of 22% (very roughly). So the slight difference in loss of heat from the hot water inside a well insulated tank to the ambient air temperature of whatever room in which it is installed will be very slight!

My electric company says that my hot water costs, typically, less than 20% of my total electricity bill. In my case as a single person less than that. So even if that could be reduced by one quarter the reduction in cost each month would hardly be significant. maybe 30 cents per day; at best?

My 0.02

Reply to
terry

"terry" wrote

Look another way. 30cents a day adds up to 30x30=9$ a month. It may not be much, but it's a decent lunch a month when eating out, or 2 at many a fast food place.

Reply to
cshenk

Yes I mean replacing my 50 gal. gas heater with a 40 gal. gas heater.

Wouldn't it cost more money to heat more water on an on-going basis? Just wondering.

Reply to
RepairNovice

That's right. If I could save $9 a month and not notice any hot water shortage, I'd go for it.

Reply to
RepairNovice

=EF=BF=BDIt may not be

i doubt the savings will be that much, ands check the first hour rating of the old and perspective new water heater. not all are the same

Reply to
hallerb

Why rent, buy it its cheaper in the long run, you will save with a smaller tank. You will also save because the new tank wont have scale at the bottom. To save more shop and compare by EF energy factor, alot of cheap ones are still 50 EF

Reply to
ransley

Check out the following:

formatting link
It's a rather indirect but valid way of guesstimating the annual savings a 1 person household would see in replacing an old water heater with a

40 gal vs a 50 gal.

So, assuming that the 40 and 50 gal heaters are equally efficient and adequate to your needs, you should save approx 20 therms per year with the 40 gal. Where I live, gas is running between $1.25 and $1.50 per therm, so that would be a $25 to $30 savings per year.

Reply to
Erma1ina

You RENT the water heater?

How does that work?

Reply to
HeyBub

More exactly, (50/40)^(2/3) = 1.16, ie 50 would have 16% more surface.

Nick

Reply to
nicksanspam

I replaced a 40 gallon tank that started leaking with a 20 gallon and had all the hot water I needed for showers and dish washing. I too live by my self.

Then I moved and had hot water off the boiler coil. That thing ran 10 or

15 times a day even if I didn't use any hot water. So I shut that off and installed 2 point of use tankless water heaters and don't regret it a bit. They only run when you actually use them. One for the bathroom sink and shower and another for the kitchen sink. I love this. The longer you use it the hotter it gets.
Reply to
Claude Hopper

Well had I known I would be still be in the same house ten years ago, I would have bought a tank then.

If I buy a new tank now and move in a couple of years I think I would lose out on the deal. A move is a distinct possibility for me in the next few years.

Reply to
RepairNovice

Thanks Erma for this info!

Reply to
RepairNovice

Yes my title does a have a poor choice of words, but I didn't say I rent the water heater, (see above) :)

Reply to
RepairNovice

Thanks Claude for your input.

My 50 gal. tank also started leaking a few weeks ago. It was about 10 years old and as I mentioned I've been renting.

They replaced it with another 50 gal. tank but I'm not happy with it. For some reason (I haven't figured it out yet) the replacement tank can be heard all throughout the house when the water is heating up.

I could never hear the original tank unless I was in the furnace room.

So when I ask the company to come back I thought I'd look into getting a 40 gal. tank instead, for cost savings.

Are point of use tankless water heaters costly? Can they be installed in any house? Thanks!

Reply to
RepairNovice

I paid $144.00 each for my tankless heaters and installed them myself. They are 25 amps so you need to run 30 amp line to each unit plus plumbing.

Reply to
Claude Hopper

Minimal difference.

FWIW, we had a 40 gallon for our family of four in our old house and we never ran out of hot water. Showers, laundry, dishwasher, it kept up with our needs.

The savings to be had are the difference it takes in gas to keep 50 gallon versus 40 gallons at temperature. This is a direct ratio of the heat loss of the two tanks as the larger tank has more surface area. In either case, if you use 10 gallons of hot water it will be replaced by 10 gallons of cold water and on either sized tank it will cost the same to bring it up to temperature.

If you heat your house in the winter there will be no savings. The heat lost from the water through the tank and into the air is just the same as the heat from your furnace or boiler that would have to run longer, so, your savings may take place only half the year or so.

I'd replace it with the easiest solution. If the connections of the 50 gallon tank line up, it is an easy swap. If, however, you'd have to re-plumb for the smaller tank, you'd probably wipe out a year or two in savings.

Reply to
Edwin Pawlowski

Well that depends. Where is the lost heat going? If it is going into the house and assisting the home heater there is really no savings at all during heating season so it may be half what is stated.

Reply to
Edwin Pawlowski

most folks used 20 galon heaters decades back no problem. even with a family

if you are in a cheap electric area. pacific northwest, an instaneous water heater will save you a lot

I can get by with a 5 gal heater in my motor home ,, 40 is gross overkill imo

Phil scott

Reply to
phil scott

Thanks Ed, this is good to know.

I was just thinking that a 50 gallon tank that needs to be kept at a certain hot temperature would require more gas than a 40 gallon tank.

I don't know how the tanks work, but I was assuming that the tank's complete contents are kept at a fixed temperature.

Reply to
RepairNovice

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.