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cowboyro
Premium Member
join:2000-10-11
CT

cowboyro to tschmidt

Premium Member

to tschmidt

Re: Electric Water Heater Timer Worth It?

said by tschmidt:

Try setting temperature close to 120 degrees. That reduces standby looses and reduces risk of scalds.
My advice: don't. Setting the temperature below 140F opens the door for development of dangerous bacteria in the tank. In fact in most countries it is recommended to NOT set the tank below 140F (60C).
scooper
join:2000-07-11
Kansas City, KS

scooper

Member

Got a link for that ?
Here the States, most hot water heaters are set to about 120 -125 F.

When I recently replaced mine - the factory setting was for 120, I boosted it to 125.

cowboyro
Premium Member
join:2000-10-11
CT

cowboyro

Premium Member

said by scooper:

Got a link for that ?
Here the States, most hot water heaters are set to about 120 -125 F.
That's because of retarded scalding lawsuits.
Back to the risk:
Avoiding water conditions that allow the organism to grow to high levels is the best means of prevention. Specific preventive steps include:
[...]
* Maintain domestic water heaters at 60°C (140°F). The temperature of the water should be 50°C (122°F) or higher at the faucet.
From »www.osha.gov/dts/osta/ot ··· faq.html

Also:
»www.treehugger.com/files ··· safe.php

Nick_L
Premium Member
join:2003-01-22
Pittsburgh, PA

Nick_L to cowboyro

Premium Member

to cowboyro
said by cowboyro:

said by tschmidt:

Try setting temperature close to 120 degrees. That reduces standby looses and reduces risk of scalds.
My advice: don't. Setting the temperature below 140F opens the door for development of dangerous bacteria in the tank. In fact in most countries it is recommended to NOT set the tank below 140F (60C).
Thank you, Im glad someone said it!

Additionally, you can actually save energy, as with hotter water you will mix more cold at the tap to get the same temp, thus using less hot water. The only thing is to make sure you alert visitors to the very hot nature of your water, or better yet install anti-scald valves in places where people might be likely to come in contact with scalding water.

toby
Troy Mcclure
join:2001-11-13
Seattle, WA

1 edit

toby

Member

said by Nick_L:

said by cowboyro:

said by tschmidt:

Try setting temperature close to 120 degrees. That reduces standby looses and reduces risk of scalds.
My advice: don't. Setting the temperature below 140F opens the door for development of dangerous bacteria in the tank. In fact in most countries it is recommended to NOT set the tank below 140F (60C).
Thank you, Im glad someone said it!

Additionally, you can actually save energy, as with hotter water you will mix more cold at the tap to get the same temp, thus using less hot water. The only thing is to make sure you alert visitors to the very hot nature of your water, or better yet install anti-scald valves in places where people might be likely to come in contact with scalding water.
Less 140-F water? Don't think that makes sense.

I have mine set to 120-F, it makes it safer and easier, just turn the hot water on all the way.

cowboyro
Premium Member
join:2000-10-11
CT

cowboyro to Nick_L

Premium Member

to Nick_L
said by Nick_L:

Additionally, you can actually save energy, as with hotter water you will mix more cold at the tap to get the same temp, thus using less hot water.
You don't save energy. Total energy used from hot water is the same, but standby losses are slightly higher (some 30% increase).
140F is far from being "scalding", I have mine set at 155F.

Nick_L
Premium Member
join:2003-01-22
Pittsburgh, PA

Nick_L

Premium Member

said by cowboyro:

said by Nick_L:

Additionally, you can actually save energy, as with hotter water you will mix more cold at the tap to get the same temp, thus using less hot water.
You don't save energy. Total energy used from hot water is the same, but standby losses are slightly higher (some 30% increase).
140F is far from being "scalding", I have mine set at 155F.
First, 130° water will cause a third degree burn in 30 seconds. 140° water in six.

Secondly, Im not sure what you are saying. If you are trying to, for instance, fill a bath tub with 110° water you would use a larger volume of cooler "hot" water mixed with your cold than if you had your tank set to produce higher temp. water. Therefore, you would be pulling less water from your tank, meaning that less cold water would have to be treated to bring it up to temp, meaning that your tank would run less meaning that you would save energy. This, of course, assumes a well insulated tank and delivery system where stand-by heat loss is minimal.

cowboyro
Premium Member
join:2000-10-11
CT

cowboyro

Premium Member

said by Nick_L:

If you are trying to, for instance, fill a bath tub with 110° water you would use a larger volume of cooler "hot" water mixed with your cold than if you had your tank set to produce higher temp. water. Therefore, you would be pulling less water from your tank, meaning that less cold water would have to be treated to bring it up to temp,
Ummm..... no. Total energy use is the same, you are heating less water but to a higher temperature
Say you want to make 4gal 100F water; cold water is 60F.
You could use 2gal of cold and 2 gal of 140F hot water.
Total energy to reheat: reheating 2gal by 80F
Or you could use 1gal of 60F and 3 gal of 113.33F water. Total energy to reheat: reheating 3 gal by 53.33F.
2*80=3*53.33
Of course assuming that the caloric capacity of water is constant with the temperature (for practical purposes it is)...

Msradell
Premium Member
join:2008-12-25
Louisville, KY

Msradell to Nick_L

Premium Member

to Nick_L
said by Nick_L:

Additionally, you can actually save energy, as with hotter water you will mix more cold at the tap to get the same temp, thus using less hot water.
You'll actually use more energy in this situation. The water you're using ends up requiring the same BTU's to achieve the desired temperature. It still takes X BTU's to raise your incoming water to the desired temperature whether you heat it hotter and then dilute it or just heat it to the desired temperature. However, heating it to a higher temperature results in more heat loss from the tank and piping no matter how well they are insulated.