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scotta
Jun 22, 2009, 09:41 AM
I have the old 60 gal. Electric hot water heater. I live alone and really all I use hot water for is to run the dishwasher every 4 to 5 days and take a shower once a day and thatís it.
So someone suggested to me that I should turn off my hot water heater from the main panel when Iím not using the hot water to save money.

So my questions are:
1. Is it safe to keep switching the circuit panel off and on as I need to turn off the hot water heater, will it mess up the heating element inside the unit?
2. How long will the water stay hot in the tank after turning it off?
3. How long before I take a shower should I allow for the tank to heat up?
4. Should I also look at what the hot water temperature is set too? Is there an average temp it should be set too?

Thanks

ballengerb1
Jun 22, 2009, 10:40 AM
Water temps are set at 120 or lower. You can use the breaker to kill the power to the heater and the water will slowly lose its heat over the next 24 hours, faster if you draw water. It would take about an hour to totally bring the temp back up to 120 once the heater has been off for more than a day. You can save money buy investing in a small point of use heater that serves just your shower or bath area. A small heater, electric and plumbing may run you $500+ but will use much less power. When that 60 gallon tank dies you can replace it with a 30 or 40 gallon tank more efficient than what you currently have.

massplumber2008
Jun 22, 2009, 10:45 AM
Hi Scotta:

1) As you suspected, it is not really a good idea to keep turning on /off the breaker as it is not a SWITCH but a breaker and it will eventually break. You are better off installing a water heater timer... sold at home depot. These are great devices that will pay for themselves quickly and reduce any need for you to worry about turning the water heater on or off!

2) The water will stay hot in the tank for hours on end... practically overnight as they are so super insulated these days.

3) Allow 1 hour time before if using the breaker or the timer.

4) The temperature should be set at 120F.

Let me know if you have questions...

MARK

scotta
Jun 22, 2009, 12:10 PM
Thank you Mark & ballengerb1 for your answers, they are very helpful... I appreciate it.

Scott

massplumber2008
Jun 22, 2009, 12:19 PM
Glad to help Scott... let us know if we can be of further assistance in the future!

MARK

Milo Dolezal
Jun 23, 2009, 08:29 AM
You are a good candidate for Tankless Hot Water Heater. Of course, it would have to be heated by natural gas. Do you have gas in your house ? Thankless heater heats up water ONLY when needed. No 60 gallons of water being reheated 24/7/365.

massplumber2008
Jun 23, 2009, 11:04 AM
Tankless hot water heater... $3000.00 or so installed... right Milo..

Water heater timer... about $50.00... only needs to come on for 2 hours a day... ;)

I don't know... timer seems best option to me.

MARK

scotta
Jun 23, 2009, 11:05 AM
Milo,

Yes I have gas leading to the house, but it is not currently connected to anything.
Will something like the tankless system be worth it just to have the gas connecting to just one item in the house?

Scott

scotta
Jun 23, 2009, 12:10 PM
Yes Mark
... sounds like the best option for now is try the water heater timer now and when my tank is ready to die on me I consider the options you all suggested.

Scott

Milo Dolezal
Jun 23, 2009, 12:15 PM
Milo,

Yes I have gas leading to the house, but it is not currently connected to anything.
Will something like the tankless system be worth it just to have the gas connecting to just one item in the house?

Scott

It really depends. Usually, start up cost for Tankless Heaters is high ( heater itself + bringing in the gas line ). But they do work perfectly in situations like you've described.

scotta
Jun 23, 2009, 12:41 PM
Thanks Milo for the info.

Joe_Bob
Nov 14, 2010, 06:45 AM
No, turning it off via a breaker or a timer for short periods saves nothing. The only savings occurs when the heater has cooled to ambient temp and remains there for some time. A 40gal tank has about 333 lbs. of water in it. Therefor, to raise the water temp 1 degree will require about 333 BTUs of energy, supplied by 97.59 watt/hrs of electricity (at 100% efficiency). So, if, your tank cools five degrees before the elements kick on, you'll use 292.7 watt/hours to heat it up. Assume during a normal day this happens three times. That's 878.3 watt/hours used. Now - during the same time, the next day, you turn off the water heater. You'll lose about 15 degrees - and when you turn your heater back on, you'll use - 878.3 watt hours to get it back up to temperature. Sorry, but those lost BTUs have to be put back, and whether you do it in one big installment, or several small ones makes no difference.

The only way you'll save money (NOT electricity) is if your utility charges a higher rate during the day.

Now - an excessively large tank (your situation) and an insufficiently insulated tank (older than about fifteen years or so) IS costing you - but playing timer or breaker games won't help there, either.

topaz18046
Jan 31, 2011, 11:40 AM
In response to a recent segment on our local current affairs t.v program (on saving money on rising electricity bills) we now turn off our hot water heater at the mains. The tank provides hot water for three
Days before needing to be turned back on... for 1 hour and 15 minutes (60 gal.) This is done after midnight
To use the off-peak rate. We are saving $100 per quarter doing this simple thing. No need to replace your tank with a smaller one or install timers etc. Check this out for yourself. In Australia the Hot water heater switch is separate from the mains switch and clearly marked. Another alternate suggestion was to lower the temperature dial on your tank. From 120 to 60. Not lower as 60, apparently, is the minimum required to kill any bacteria that would otherwise breed.

pghplumber
Jan 31, 2011, 04:48 PM
I don't agree with dropping water temperature for any reason or for any period. The 120 degree F. temp was established primarily to keep the possible cultivation of legionella bacteria at bay. If bacteria form in the HWT then the temp must be increased to approx. 165 degrees for about 45 minutes to Pasteurize the tank. Then the temperature reduced back to minimum 120. The concern of Legionnaires disease comes from the bacteria entering the body while showering. Most naturally occurring bacterium and viruses are destroyed by agents in the water or by your body because their numbers are too small. By allowing a tank to warm then cool sounds like a science experiment to help the few organisms that exist to grow in numbers and strength. That's just my opinion, but maybe the "current affairs" people know something that I don't.

pghplumber
Jan 31, 2011, 04:58 PM
My post is referring to temperatures in Fahrenheit. 60 degrees F. is not hot water and is probably the temperature of the cold water entering the home. There may have been a misunderstanding on the info given from the t.v. program.