Rheem MR105245 Marathon Electric Water Heater 105 Gal Logo
Posted on Jan 25, 2011

Enough hot water for 1 bath. Replaced upper and lower elements and replaced both thermostats. could it be a sedament problem? heater is 5 years old. I never ran out of hot water before now.

1 Answer

A

Anonymous

You have 240Volt Marathon water heater.
These heaters have element burn-out problems.
http://www.thetankatwaterheaterrescue.com/forums/forum3/

Yes sediment can cause decreased amount of hot water when water cannot circulate around lower element, and sediment can cause lower element to burn out.
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html

Following list is overview of tank troubleshoot:

If you have some hot water, then that says several things:
-Upper element is working.
-Electricity from circuit breaker to upper thermostat is good.
-ECO reset button is not tripped.
-You do not have overheating event.
-Access doors and insulation are in place and thermostat not exposed to cool temperature that causes overheating.

That leaves following suspects:
1) Check if TP valve is stuck open, or pipe cracked, or faucet leaking and running hot water down a drain.

2) Upper or lower thermostat is bad.

3) Lower element is bad -and- maybe tank has built-up sediment
http://waterheatertimer.org/How-to-test-water-heater-element.html
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html

4) Loose wire. Open covers and inspect. Tighten screws very tight against copper wire.

5) Bad wire between upper and lower sections of tank.

6) Do complete 30 minute troubleshoot before replacing any parts.
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

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

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

Electric wh high temp shut off button keeps resetting

Water heater has upper and lower elements. Only one t-stat. Check to see where tstat is set to. Turn down to lowest level. If breaker still resets then replace tstat. It is letting the water get to hot no matter what setting it's on. So water is getting so hot that it trips breaker.
0helpful
1answer

Water heater

Guessing that you have 240Volt residential non-simultaneous electric water heater? And that you have 30 amp breaker and 10 gauge wire. And that water heater is located within 100 feet of breaker box. And there are no leaks running hot water out of tank. And that you installed fully brand NEW elements of same wattage as old elements. And that fully brand new thermostats were installed, and wiring exactly duplicates wiring that was present before. And that factory-insulation was re-installed over elements and thermostats.

1) Guessing the 'hot water shut off' means the ECO red reset button located on upper thermostat keeps tripping and cutting off electric power to water heater?
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html
http://waterheatertimer.org/images/WH-w-combined2-1000.jpg
http://waterheatertimer.org/How-to-test-water-heater-wires.html

2) If the ECO is tripping, then water is getting too hot, or there is shorted wire located near the upper thermostat, .
Typically replacing both thermostats and replacing elements will solve this problem .... assuming that new thermostats and elements are good, and wiring correct.
Double-Check your wiring on upper and lower thermostats.
Test wires for short.
Make sure factory-insulation is re-installed over thermostats so cool room temperature will not affect temperature reading.
Check that thermostats sit flat against steel tank.
Many short draws hot water can also cause stacking event that will trip circuit breaker.

3) Add comment and say what you find using checklist above.
Be careful to explain findings fully, using same words found on links above, so illuminated diagnosis can be made.

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

2helpful
1answer

Got 5 minutes of hot water then cold. replaced both elements and thermos. still 5 minutes of hot water. power bill increased nearly 400% in 30 days. HELP!!! please.

When the top of the tank is hot the upper thermostat removes power from the upper heating element and transfers the power to the lower thermostat and heating element. If the lower thermostat is defective, then the lower portion of the tank will not be heated and the supply will be greatly reduced. You replaced both elements however check that the lower element is coming on after ther upper one cuts out and is acutally working.
Check for power at the upper thermostat terminals where the power is sent to the lower thermostat and heating element. If there is no power then the upper thermostat should be replaced. If there is power then check for power at the lower heating element. If there is no power at the lower heating element then replace the lower thermostat.
If there is power to the lower heating element then it should be getting hot. If it is not, maybe defective. Another possibility is a broken dip tube. Check for a broken dip tube and replace if necessary.

If the dip tube is broken, the incoming cold liquid can mix with the out going hot liquid and cause it to seem as though you are running out.
0helpful
1answer

Hi...I have a Whirlpool water heater and the water only stays hot for a few minutes. How do I adjust the temperature or settings so that I can have hot water all the way through the shower instead of...

I am guessing this is an ele water heater and the temp setting are not the problem.
Problem: Not enough hot water or water temperature too low. When the top of the tank is hot the upper thermostat removes power from the upper heating element and transfers the power to the lower thermostat and heating element. If the lower thermostat is defective, then the lower portion of the tank will not be heated and the supply will be greatly reduced.
Check for power at the upper thermostat terminals where the power is sent to the lower thermostat and heating element. If there is no power then the upper thermostat should be replaced. If there is power then check for power at the lower heating element. If there is no power at the lower heating element then replace the lower thermostat.
If there is power to the lower heating element then it should be getting hot. If it is not, replace it. Another possibility is a broken dip tube. Check for a broken dip tube and replace if necessary.

The dip tub is located under the fitting where the hot water comes out.
0helpful
1answer

Not getting enough hot water

You posted under Rheem 40 gallon tank-type electric water heater.

You have some hot water so that says specific things:
-Upper element is working.
-Electricity to water heater and circuit breaker are good
-You don't report a leak so TP valve is good
-You are not experiencing overheating event
-ECO reset button is not tripped
-Insulation and covers are in place so thermostat not exposed to cooler temperatures that would cause thermostat to misread temperature and cause overheating.

That leaves 6 suspects listed in order of difficulty:
1) Leaking faucet or broken water line that is running hot water all the time and tank cannot keep up.

2) Thermostats set too low. Turn power OFF, open covers and check each thermostat.
http://waterheatertimer.org/How-to-adjust-temperature-on-water-heater.html

3) Loose screw, loose wire at upper thermostat, lower thermostat, or lower element. Turn power OFF and tighten screws, and look for signs of high heat and burning, especially on lower element.

4) Upper or lower thermostat. Replace both thermostats for $28 and see if that corrects problem.
Parts available at home center, hardware, or plumbing supply
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

5) Defective wire between upper and lower sections of tank: If this is the case, and water heater has 2" foam insulation, then tank usually replaced since insulation is too dense to drop another wire. Call for manufacturer for warranty information. Do a full troubleshoot using multimeter.
http://waterheatertimer.org/Water-heater-manufacturers.html
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

6) Lower element is burned out. Test lower element. Replace lower element. Rheem elements are 4500 Watts and are available at home center, hardware, or plumbing supply
http://waterheatertimer.org/How-to-test-water-heater-element.html
http://waterheatertimer.org/How-to-replace-element-and-clean-sediment-out-of-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 water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.
0helpful
1answer

I have an electric Hot water heater with two elements. A few months ago we replaced the pop off valve and a year ago we replaced the thermostat.Since yesterday, we have not hot water. So my husband...

Replace the melted part.

If tank is popping breaker, then the melted part has a short circuit.
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html
When replacing thermostats, I usually replace both of them
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

There are 5 basic parts to electric water heater.
Electricity to water heater.
Upper thermostat
Upper element
Lower thermostat
Lower element
It sounds like electricity is good.
Elements are probably good if just replaced, but one of them could have a short.
Thermostat is melted, so replace it and see if it restores hot water.
If not, then take 40 minutes and do complete troubleshoot as shown in link above.

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 timer or any do-it-yourself project.
Fixya is always less expensive than a service call.
0helpful
1answer

Replaced both lower and top elements and upper thermostat still no hot water. proper elec. going to unit.what could it be?

You need to take 1/2 hour to learn basics and then test water heater parts before replacing anything.
http://waterheatertimer.org/How-to-troubleshoot-electric-water-heater.html
Follow the troubleshooting steps, and it will tell you exactly where the problem is.
Otherwise we can guess at 20 different things.

Water heater is 240V because you have more than 1 element.
Did you test for 240V across top two screws of upper element?
Breaker can be tripped off on one leg and 120V arrives at water heater so heater looks like it has electricity, but circuit is not complete.

The problem can be loose wire, bad 240V circuit breaker, sediment reaching lower element, bad thermostat, bad upper element, tripped ECO reset button.

Did you replace factory insulation and cover over thermostats after replacing elements?
Did you vacuum out sediment when replacing lower element?

How long ago did you replace elements? If you turned power ON before tank was completely filled with water, then you burned out the element. If upper element is burned out, the tank has no hot water, even if lower element is good.
Test the upper element:
http://waterheatertimer.org/How-to-test-water-heater-element.html
See how a water heater works:
http://waterheatertimer.org/How-it-works.html

And finally, why so many folks write to fixya saying they replaced both elements and upper thermostat, but they never replace lower thermostat for another $6? I have been puzzled about that since lower thermostat turns on and off each time tank temperature drops and is responsible for keeping water warm during standby hours. Lower thermostat cycles more times than upper thermostat.

Add a comment if you need specific assistance with any of the testing steps.
1helpful
1answer

I have a Reliance 501 water heater, when I take a shower now I only get about 5 min. of hot water is there something on the heater I have to reset? Thnx Mike

Electric water heater is fully repairable by homeowner.
Following information will tell you how.

1) Background on your heater:
Reliance is AO Smith company.
http://www.aosmith.com/OperatingUnits/Detail.aspx?id=138&ekmensel=c580fa7b_12_0_138_3

Age of water heater is shown in serial number. First character is letter. Second 2 characters are numbers, which are year of manufacture. For example 05 is year 2005.

The 501 manual is not shown on Reliance website:
http://www.reliancewaterheaters.com/prod/elec.html

2) Two things known for sure:
- electricity is OK
- upper element is working because there is some hot water.

3) Three things can cause problem you describe:
- Loose wire located from upper thermostat to lower element and thermostat.
- Upper or lower thermostat is bad
- Lower element is burned out

4) How to troubleshoot and repair
- Turn off power, open covers and look for loose and burned wiring, especially on lower element.
- When finished, put back insulation and covers so thermostat not exposed to cooler temperatures.
- Burned wire on lower element is evidence that lower element is burned out.

- If you do not want to follow testing steps below, next step is to replace both upper and lower thermostat for about 25$ and see if problem persists.
- If problem persists, replace lower element.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

5) Test lower element, before replacing anything
http://waterheatertimer.org/How-to-test-water-heater-element.html

6) Troubleshoot electric water heater
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

7) How to replace lower element and clean sediment out of tank:
http://waterheatertimer.org/How-to-clean-sediment-out-of-electric-water-heater.html
0helpful
1answer

Not enough hot water

Makes you feel good to save some money right? Have a great day!
Not finding what you are looking for?

344 views

Ask a Question

Usually answered in minutes!

Top Rheem Water Heaters Experts

Mike Cairns
Mike Cairns

Level 3 Expert

3054 Answers

Brad Brown

Level 3 Expert

19187 Answers

Sean Wright
Sean Wright

Level 3 Expert

2045 Answers

Are you a Rheem Water Heater Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...