How to change heating elements

SOURCE: heating elements do not operate together

That's how they work. First you need to know that cold water goes into the tank near the bottom (because of the "dip tube" inside the tank) and hot water is taken out at the top. Also hot water naturally rises.
so... when the tank is full of cold water the top element will come on and heat up the top 1/3 of the water then the bottom element will come on and finish heating the rest of the tank

electronic & computer repair& servicre

• 12061 Answers
• Posted on Feb 10, 2010

SOURCE: I can't get 240v across the bottom element. Where

If that is indeed so you have a "Short" between Phase and Earth. .. YES one should have the mains Voltage across the Load, But NEVER anything between Phase & Earth. Look think of it all like this. The Phase comes in, to a, say, a switch, from switch, to thermostat, from thermostat, to One Side of the "Load" Element. The "Other side of that "Load" Element then goes to Neutral. Circuit Complete. Two elements, wired in series would indeed split the Voltage, if wired that way. If done like this, but if wired in parallel, then, again Both would have One End, connected to Phase, & the "Other" side(s) would go to Neutral. Thus the circuit is complete. Some setups are more complex, and use two elements. but essentially all the same. The elements could be wired in series or parallel, depending on current draw/resistance. The Phase is the wire always "Broken" and the Neutral is always "Common".
BE CAREFUL.

SOURCE: Top heating element was broke. Replaced got hot

look for a badly connected power line ont he bottom element, or any connection upstream of the power terminals. voltage readings usually drop to that range when you only have one side of the 220v circuit connected.

SOURCE: What is the energy factor for the mod.82V80-2? I

http://www.rheem.com/product.aspx?id=09DF2BDD-5E11-4D32-B574-84ACFB8A4619
http://globalimageserver.com/fetchDocument.aspx?id=052c9e32-ce37-48d7-8990-9e430f23fef3

82V80-2 Energy factor is .86 according to water heater industry self-regulated standards.

Rheem pdf says these water heaters are wired for non-simultaneous operation.
Except special order water heaters.
Non-simultaneous operation uses single 240V circuit as described below.
If your water heater is wired for simultaneous operation, and each element is on a separate circuit, that makes your water heater special order. I would guess the reason is for higher first-hour delivery, which implies rapid heating and would likely affect energy factor.
You might want to get serial number off model and call Rheem for specs on that special order.

Your water heater energy factor may be the same because 'energy efficiency is based on the amount of hot water produced per unit of fuel consumed over a typical day.' This means an aircraft carrier can be considered highly efficient despite overall cost. And naturally the guys making the aircraft carrier are also doing the rating.
http://www.energysavers.gov/your_home/water_heating/index.cfm/mytopic=13000

Non simultaneous operation means the upper thermostat controls heating functions.
240V goes to upper thermostat first.
When water inside tank is cold, thermostat reads temperature through tank wall.
Upper thermostat turns on upper element until top 2/3 of tank reaches thermostat set point.
Once set point is reached, upper thermostat turns off upper element and sends power to lower thermostat and lower element.
Lower thermostat reads temperature through tank wall, and turns on lower element until bottom 1/3 of tank reaches thermostat set point.
As water cools inside tank, lower thermostat is first to respond since hot water rises.
Lower thermostat turns on lower element until tank again reaches set point.
When hot water faucet is turned on, hot water exits top of tank.
At same time, cold water enters bottom of tank through the dip tube.
The heating cycle repeats.
At all times, the electricity flows through upper thermostat. And upper thermostat is powered by one 240V circuit.

With simultaneous operation, the upper and lower thermostats work in same manner.
Except thermostats are wired separately.
Lower thermostat does not wait for upper part of tank to be heated first.
Lower thermostat turns on whenever lower part of tank cools.
The advantage is more hot water available rapidly when demand is high. This is called first hour recovery.

One method for reducing electric consumption is to set lower thermostat so it only turns on during certain times of day. For example Whirlpool Energy Smart operates in this manner and shaves a few bucks off the bill each month. This says that simultaneous operation is not an energy saver, unless that circuit controlling lower thermostat is set on a timer.

SOURCE: No hot water from my Rheem 72-40-1, I replaced the

Open following link to look at thermostat wiring
http://waterheatertimer.org/How-to-wire-water-heater-thermostats.html

If you have dual element electric water heater, then that is a 240Volt water heater.
http://waterheatertimer.org/240-v-water-heater-circuit.html

If you are replacing lower element several times, are you also cleaning out the tank?
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html

Are you installing same wattage element shown on label on side of tank: Should be 4500Watts.
http://waterheatertimer.org/Figure-Volts-Amps-Watts-for-water-heater.html

If upper element burns out, then tank will have no hot water:
http://waterheatertimer.org/How-it-works.html
http://waterheatertimer.org/How-to-test-water-heater-element.html

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