Seems less hot water than before


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Old 01-12-11, 10:37 AM
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Seems less hot water than before

I used to fill my bathtub with completely hot water and it was almost too hot to tolerate. And I still had more hot water left. Now I fill my bathtub with completly hot water and it is not as hot as it used to be. I am also out of hot water after. Seems like I don't have as much hot water as I used to. Below are links to pictures of my wiring diagram, upper element and lower element for my Bradford White water heater.

I turned off the power. I touched the screw heads of the upper element blue and yellow wires with my ohm meter and got a reading of 13. I touched the screw heads of the lower element red and black wires with my ohm meter and also got a reading of 13. Does that mean my elements are good?

Wiring Diagram:
http://i960.photobucket.com/albums/a...ireDiagram.jpg

Upper Element:
http://i960.photobucket.com/albums/a...perElement.jpg

Lower Element:
http://i960.photobucket.com/albums/a...werElement.jpg

Thanks,
Troy
 
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Old 01-12-11, 10:48 AM
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I disconnect the wires from the heating element before testing just to make sure I am not getting continuity through something else (thermostat, shorted wires) but you are on the right track. If you did not have continuity through one elements pair of contacts it would indicate that it was burned out (open circuit).
 
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Old 01-12-11, 11:05 AM
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I removed the screws and checked the wires for ohms. Again both top and bottom elements showed 13. I reconnected the wires and screws and turned on the power. I checked the screw heads on the bottom element and got 238 volts. I checked the screw heads on the top element and got 0 zero. Could it be my top element is not getting electricity? Or could it be a timing issue that the top elelemnt had not kicked in yet?
What about that Reset button? Should I push that while the power is turned on and see if anything changes?
 
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Old 01-12-11, 11:08 AM
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I think your numbers are about right..but I agree with disconnecting the wires. If the elements check out then I would be looking at a bad lower thermostat (which does most of the heating IIRC) or a bad diptube. A bad/broken diptube will allow incoming cold to mix with hot and lower the outgoing temp and reduce the amount of hot water as well.

Please give the serial number if you are not sure of the age of the WH.
 
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Old 01-12-11, 11:27 AM
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I thought it was opposite. The upper element operates first. Once it's up to temperature the upper element turns off and power is sent to the lower thermostat. If the lower thermostat says it's too cold then it turns on the lower element. That's why the power coming into the water heater is routed through the upper thermostat which has extra contacts and does double duty.
 
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Old 01-12-11, 11:38 AM
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I will look for the S/N of my water heater, but it will require me removing some tape and insulation. I started all this shortly after I took a bath. So I expect water in both upper and lower takes would be cool. The lower element is getting power, 238. The upper element is getting none. When would the upper element get power? Perhaps after the lower thermostat reads it is hot enough?
 
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Old 01-12-11, 11:44 AM
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Could be PD...my bad if so...but from what I can find...since the cold come in at the bottom..that's the first element to kick in during normal usage. This is AFTER the tank has been filled and heated to the point that both elements are off.

http://eet.canton.edu/~eet/Sequence%...r%20heater.pdf
 
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Old 01-12-11, 12:49 PM
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I consulted the PDF file provided by GunGuy. I confirmed there is always 120 volts going to both elements. I also confirmed that when the water heater was full of hot water and I started using hot water, the bottom element comes on first. It received the extra 120 and started heating with the 240 volts.

The PDF file said "when the take is full of cold water, the upper thermostat will take priority and heat the top portion". So I turned off the power and turned on all the hot faucets in the house. I drained all hot water out of the tank. With the tank full of cold water, I turned the power back on. I confirmed the top element was getting the full 240 volts and heating the top portion first. So my thermostats and elements seem fine.

The tank is set to the lowest heating setting. Maybe I just need to turn up the heat a little bit. Or, maybe I do have a bad diptube and cold water is mixing with hot water. I guess I'll have to research how to test that. I'm done messing with it for the day. Thanks, Troy
 
 

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