Gas water heater on 'vacation' setting

[Walter Cohen]

I live in New England and will be vacating my house for 4 days next week. I was wondering if it makes any sense to turn my gas water heater to the 'vacation' setting.

Thanks, Walter

[Jonathan Kamens]

Yes.

If your water heater is pretty new, you may not save much, but you'll save something, and you certainly won't lose anything.

[John Davies]

I turn mine to Vacation any time I am gone more than a couple of days.

John Davies

'96 Lexus LX450 '00 Audi A4 1.8T quattro Spokane WA USA

[v]

What the heck is the "vacation" setting? Guess its been a while since I bought a water tank? Didn't know there was such a thing. Is this just the same as turning it way down? Or turning it to Pilot? Or couldn't he just turn it off? Do people need a pre-imprinted label to tell them to do what they always could, or is that actually some kind of new feature that has characteristics of I don't know what?

Assuming it is *some* kind of temperature reduction, this would only save $ if the reduced standby loss for the period in question, came to more than the btus to re-heat the existing hot water that is now being allowed to cool down. Now for 4 weeks it seems like it gotta be a savings. For a couple of days it seems pretty marginal if at all.

-v.

[Jonathan Kamens]

The thermostat dials on most new water heaters nowadays say "vacation" at the low end of the dial. I.e., yes, it's the same as just turning it down all the way.

You save money if the thermostat is turned down for long enough to allow the water temperature to drop lower than it would have if the thermostat hadn't been turned down, even for an instant. Whether you save a *significant amount* of money is a different question. Four days is probably pushing it for a decently insulated modern water heater, but it's so easy to turn the heater down when you leave and up when you come back, that it's not even worth worrying about where the break-even point is -- just turn it down!

[HA HA Budys Here]

If there's no risk of freezing, heck just turn it OFF!

[Bruce]

Walter, If you want to save a few more cents you should do the following before you leave home:

• Turn off / down your water heater before you take your last shower so you don't heat the water up only to let it cool down while you are gone.

• Unplug all your TVs. They use power even when they are off so you won't have to wait for the TV to warm up when you turn it on.

• Unplug all your clocks and anything else that has a clock built in (e.g., microwaves, VCRs, etc.). You won't be there to use them so unplug them.

• Better yet, throw your main breaker so all power to the house is off. Sure, all your food will be ruined in your refrigerator and freezer but think of the pennies you will be saving. (My cousin actually did this. Several hundred dollars in food were ruined to save a few cents.)

My point here is that your savings will be minimal if you are only going to be gone for 4 days by turning down your water heater. If you plan to be gone for a month it might be worthwhile to turn it down but you will have to remember to turn it back up when you get home.

If you really want to save money at your water heater install an insulating jacket around it (available at any hardware store). That will give you year-round savings.

Another way to save money at your water heater is to only heat the water hot enough for your needs. It is inefficient to heat water hotter than you need only to mix it with cold water at the faucet. Don't turn it down lower than the temperature recommended for your dishwasher. And it is dangerous to heat the water to the point of scalding (especially with small children in the house).

Bruce

PS -- someone mentioned a "water tank" in this thread; is that another name for a water heater? Interesting terminology; I think of a tank as something that only stores water, not heat and store it.

[Jonathan Kamens]

Pretty much every water heater on the market nowadays has enough insulation inside it that adding additional insulation is pointless. You only need to add insulation if the outside of the heater is warm to the touch when you put your hand on it. Even then, if it's a gas heater, you have to be careful when adding the insulation not to block the area around where the thermostat and pilot light are.

[HeatMan]

Good point, but I have spoken with WH manufacturer's reps and they tell me the gas train draws air from the bottom of the heater and not the pilot door.

[John Gilmer]

Or just put it down to PILOT. (It's a PITA to re-light the pilot flame.)

"Luke" warm water tanks sometimes become biological reactors. Expecially if you are on well water.)

[v]

No, because that ignores the cost to re-heat the water back up.

Yes, it saves on standby loss, even for an instant, yes the lower the temp the less the standby loss. But as we both recognize, standby loss for short periods is not all that great.

Now here is the flip side. Here is an exercize.

You pay to heat a tank full of water from, say, 50 degrees incoming up to 130 degrees. Then you turn the heater all the way down - heck, off

- it drops to 60 degrees. Then you turn it back on, and heat a full tank of water from 60 to 130 degrees (maybe you use 1 cup of HW maybe you don't). Then turn it off again. Then on. Etc. etc. You could heat the same tank over and over, and whether this is a NET savings has to do with how much you would have lost in standby over the period. E.g., was there a long enough stanby period so there is enough standby savings to offset the re-heating of the water.

Ehh whatever, I wouldn't bother for less than a week, or even 2.

-v.

[Bill Seurer]

You'll save money. It's the same as for turning down the heat on a house. It takes more energy to keep something hotter than to reheat it. It's physics.

[MAG]

Of course, one factor people don't often think of is "is it winter or summer?" If it's winter, the "standby loss" actually represents heat that goes into the house (presuming the heater is in the enclosed heated home), so it isn't "loss." Maybe it's not the most efficient use of the engergy, of course...

In the summer, the equation goes the other way and "standby loss" becomes doubly problematic because not only is that heat lost from the water, but it adds heat to the house that must be removed via AC...

Marc

[Stormin Mormon]

With the original poster's question, there woulda been three or four days when the tank was at a lower temp. Lower temp means lower heat loss.

The first several hours (while the tank is cooling down to vacation temp) there is no gas use beyond the pilot. And reheating it is the same BTU's that woulda been used anyhow, when the cold water came in.

I suggest that turning it down does save gas, but not very much.

[Wayne Boatwright]

"Stormin Mormon" wrote in news:c05de6 $12oppg$ [e-mail]:

In cyclically reheating water to maintain a tempeature, it certainly does take more gas to maintain a higher temperature in the tank, even thugh the burner runs at the same heat and BTUs, it runs less often.

[Jonathan Kamens]

If you *don't* turn the heater all the way down, the same energy that would have been expended to heat it back up from 60 to 130 degrees is instead expended to keep the water hot.

In fact, as other people have pointed out, *more* would be expended to keep the water hot, because (a) heat loss is greater when the water is hotter and (b) a water heater shutting on and off cyclically is less efficient than one running constantly to heat up cold water.

And incidentally, it takes a long time for hot water in a modern water heater to get from 130 down to 60 degrees. That is, I suppose, an argument for not bothering to turn down the heater when on vacation, but it doesn't change the fact that regardless of how long you are gone for, you will always save *some* money by turning the heater down; it just may not be that much.