water heater elements

[prd823]

I read somewhere that there is a difference in electric water heater elements. There are "standard" ones and then there are some that are"low watt density". From what I read the "low watt density" are supposed to be more energy efficient? Is this true? Also, do you know anything about an element called a "sandhog" or something like that. It is a very curvy element that is supposed to last for years?
Also, do you think that you save energy by having the thermostat on 120 versus 140? I feel like at 120 we use more hot water showering than we would at 140 plus the dishwasher runs a long time at 120 heating the water.
Appreciate any thoughts/advice you have on this.

[got_nailed]

I have not heard of a sand dog element. But with hard water you can put in a stainless element that will not burn out. Most of the times the lower element will burn out because of build up that forms in the bottom of the tank. This is why some people will drain off part of the tank every few months to try and flush it out. Where I live (very hard water) I say it should be a monthly thing.

As far as energy savings to heat water it will cost the same no matter what wattage or type of element you use. You use the same amount of watts to do the same amount of work. But if there is a build up of deposits or a bad dip tube it will take longer to heat the water so it will cost more. The water temp is up to you. With kids I would go with the lower setting.

As far as the water temp IMO the cost in hot water is to heat the water. Once it is hot and no water is being used I don’t think it makes a difference on the energy bill to keep it hot (this is based on the newer heaters; but not in a cold unheated room). If you don’t keep up with flushing the tank then you will run into more problems in down the road.

Depending on how old it was and if you can get most of the build up out of the heater I would replace the upper and lower thermostats and elements. I would not get any high $$ top of the line “sandhog” or stainless elements.

I’ll try to find a post on flushing the heater and edit it in for you.


edit
This post has some good info on the build up and how to clean them out.
http://www.terrylove.com/forums/show...ghlight=heater

[GrumpyPlumber]

At 3:am your paying for hot water to sit in a tank.
You can have it heated to 120, or 140.
140 takes more energy, on the other hand does 120 give you enough to take all the showers your family needs?
The dishwasher will heat the water, if it takes longer it's making up the time it would have taken your tank to heat...6 of one, half dozen of the other.
It all boils down to "3:am".

[Cass]

Where I live the time zone changes about 50 miles due west of me so will that make any difference in your 3 AM scenario?

[GrumpyPlumber]

Where I live the time zone changes about 50 miles due west of me so will that make any difference in your 3 AM scenario?

Yes, by 3.2476 degree's minus the tangent of the obtuse perpendicular angle.

[hj]

Sandhog elements are stainless steel nichrome so they can operate without being immersed in water without burning out. They are my choice for replacing lower elements. High watt density elements are a single loop so they operate at a higher temperature, which causes more sedimentation to form on them, which gives them a shorter life.