I AM REPLACEING MY 4500 W WATER HEATER WITH A RHEEM 5500 W HEATER. I HAVE A 30 AMP BREAKER AM I OK WITH THAT.

Probably not. The wire and circuit breaker would both have to be upped in size. Then the thermostat's may not handle the extra amps. The higher watt element won't make the water any hotter, but will make the recovery of hot water faster.

Jan 2013
1) Water heaters can be wired many different ways.
Copy following link For ordinary household 240Volt water heater, the heater is wired for non-simultaneous operation:
http://waterheatertimer.org/images/WH-w-combined2-1000.jpg
Copy following link For other wiring diagrams, including off-peak, simultaneous, redundant, etc
http://waterheatertimer.org/How-to-wire-water-heater-thermostats.html

2) Make sure water heater circuit breaker and wire size matches watt rating that shows on end of each element.
http://waterheatertimer.org/Color-codewire.html

3) Non simultaneous means only 1 element is ON at a time.
So either upper element is ON, or lower element is ON, or both elements are OFF.
Both elements are never ON at same time.
So non-simultaneous water heater with two 4500 watt elements has total connected watt rating of 4500 watts. Because only 1 element can be ON at a time.
Use 30 amp breaker and 10 gauge wire.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

You have dual-element 240Volt electric water heater.
Since you have some hot water, then we know upper element is good, and that circuit breaker and electricity to water heater are good.
Not enough hot water is probably bad lower element, and possibly sediment build-up in bottom of tank.
Test element:
http://waterheatertimer.org/How-to-test-water-heater-element.html
Replace 4500 watt element available at local hardware, and clean out bottom of tank:
http://waterheatertimer.org/How-to-replace-water-heater-element.html

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Is this breaker connected to water heater?

1) A double 20 amp breaker is called a 240Volt breaker.
20 amp breaker is actually rated for 16 amps for safety margin.
It is also important that this breaker have 12 gauge wire which is color-coded yellow.
Look at label on side of water heater for wattage of unit.

2) For example 4500 Watt water heater is typical.
4500 watts divided by 240Volts = 18.75 amps which is nearly full capacity for the 20 amp breaker, and is slightly above the safety margin.
http://waterheatertimer.org/B220C.html

3) If breaker is getting old, and it works at full load each time water heater is on, it can wear out.
Open circuit breaker box and replace breaker:
http://waterheatertimer.org/How-to-replace-circuit-breaker.html

4) You can also move circuit breaker wire to another same-size breaker and see if problem continues.

Add a comment for more free help.
Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

It's probably bad upper or lower thermostat.
BUT... new element could also be shorted.
OR ... original tank is rated 1500 watt elements look at label on side of tank.
I always replace both thermostats to save time.
Lower thermostat costs $10 at Lowes.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

Add a comment for more free help.
Also take advantage of fixya phone service.
For a price, expert speaks with you over phone while you work on heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

You have electric water heater.
Electric water heaters are fully repairable by homeowner, excluding hybrid type.

Rheem electric water heaters:
http://www.rheem.com/products/tank_water_heaters/electric_water_heaters/
Rheem fury series manuals and models
http://www.rheem.com/product.aspx?id=09DF2BDD-5E11-4D32-B574-84ACFB8A4619

Age of Rheem water heater is shown first 4 digits of serial number located on side of tank: for example 0705 means July 2005.
Serial number also shows model number & wattage of elements in case you need to buy new generic 4-bolt type 4500 Watt element from hardware store.

A) If your water heater receives very cold incoming water, it may not heat fast enough to keep tank warm.
Add a tempering tank.
http://waterheatertimer.org/Tempering-tank.html
Add insulation over entire water heater except TP valve. Insulate pipes completely.
Read more information:
http://waterheatertimer.org/9-ways-to-save-with-water-heater.html

B) 40 or 50 gallon water heater is 240Volts and tank will have 2 access panels on front.
Rheem ships all water heaters with 4500 Watt elements.

Narrow down the suspects:
C) Water heater has some hot water.
This tells us upper element is working.
And that water heater electricity is working.
And that reset button is not tripped.
And that heater is not experiencing run-away overheating event.

That gives us 3 solid suspects.
1) lower element is burned out. Test lower element using inexpensive multi-meter from Home Depot.
http://waterheatertimer.org/How-to-test-water-heater-element.html
Replace element with same wattage shown on label, and clean out sediment:
This will restore water heater to full 99% efficiency.
http://waterheatertimer.org/How-to-clean-sediment-out-of-electric-water-heater.html
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html

2) Upper or lower thermostat is bad. Replace both thermostats for about $25.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html
If you want to test thermostats and all parts before replacing anything:
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

3) Burned or shorted wire. Turn off power. Open covers on side of tank. Remove insulation. Inspect parts for signs of high heat and burning. Especially lower element. Tighten any loose wires. Replace part that shows signs of burning.
Put insulation and cover back over thermostats so cooler outside temperature doesn't cause thermostat to misread tank temperature.

Rheem 4500 watt element

Electric water heater can be repaired by homeowner
If I understand correctly, water heater is producing no hot water.
Reset button clicks in, but still no heat.

Three initial things can be causing this:
1) No power to water heater. Test across top two screws on upper thermostat for 240V. Red and black wire are attached to these screws. Screws are marked 1 and 3. Upper thermostat is same that has reset button. If power tests 120 across screws, then breaker may be off on one leg. If no power, then start testing at breaker.
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

2) Upper thermostat is bad. Replace thermostat with generic upper thermostat available at hardware store.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

3) Upper element is bad. Test and replace element using Rheem 4500 watt element available at hardware store. Image shown below. Look at label on side of tank for element wattage. Rheem puts 4500 watt elements into all their 240V electric water heaters.
http://waterheatertimer.org/How-to-test-water-heater-element.html

If upper element is burned out the tank will not heat any water.
http://waterheatertimer.org/How-it-works.html

Rheem 4500Watt element


Upper thermostats are generic and interchangeable:

The Rheem water heater uses 4500 Watt elements
Check label on side of any appliance to see electrical rating details
2 element tank with two 4500 watt elements is still a 4500 watt appliance since both elements are never ON at same time.

Volts x amps = watts
amps = watts divided by volts

amps = 4500 divided by 240Volts or 220Volts
amps = 18.75
Your water heater uses 18.75 amps to 20.45 amps

Your 25 amp breaker should only carry 80% of rated value
25 amps x 80% = 20 amps.

So your water heater breaker is correctly sized.
You should have a 10 gauge wire going to this water heater.
12 gauge wire is a bit undersized for 4500 Watt water heater
Feel the water heater wire to see if it is warm.

If the main breaker is getting hot when 20 additional amps are being used by the water heater.
1) The house is using more amps than your 100 amp main can carry
Using the formula, 100 amps x 80% = 80 amps for the main breaker
Add up your total amp draw.
For example if your 3500 watt oven is ON, it draws 16 amps.
If your 5000 Watt electric heater is on, it draws 23 amps.
Your 1500 Watt 120V microwave draws 12.5 amps.
Add these numbers up plus your water heater, and it comes to 71 amps.
71 amps is getting close to the max 80 amp, but it's not over.
Now if you have a pool pump and and hot tub and a table saw going, the main breaker could be overdrawn.

2) To solve the problem short-term, you can put a timer on the water heater and use it only when needed.
http://waterheatertimer.org/Compare-13-electric-water-heater-timers.html

3) The main breaker is bad and needs to be replaced.

If you need help figuring circuits or timers, add a comment and I will help

The water heater has two 4500 watt elements.
However both elements are not turned-ON at same time
So the water heater is 4500 Watts

Volts x Amps = watts
Amps =watts divided by volts
Amps = 4500 Watts divided by 240 Volts
Amps= 18.75

So that says a 20 amp breaker ... except for the 80% rule
80% rules says for safety, your Amp rating should be multiplied by 80%

20 amp breaker X 80% = 16 amps
20 amp breaker is actually safe for just 16 amps, and your water heater draws 18.75 amps.

The calculation shows you need a 30 Amp breaker.
30 Amp breaker requires 10 gauge wire.

http://waterheatertimer.org/Figure-Volts-Amps-Watts-for-water-heater.html

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