Water temp varies, sometimes only luke warm

[Left-is-Hot]

My water temperature seems to fluctuate a lot. Lately usually it's barely warm enough to shower in. I'm wondering if there may be some sort of thermostat inside there that is failing. If so, is it usually a replacement part that I can buy at home depot or my local plumbing store? (I'm good at fixing stuff)

[havasu]

Bump to top............

[Left-is-Hot]

Not sure what that means

[havasu]

Is it electric or gas? Have you drained the sediment out of it? If electric, one of your two heating elements could need replacing. A thermostat usually does not go bad, but the thermocoupler sometimes does, but your gas (if equipted) would not fire or stay lit.

[phishfood]

I had a nice long reply typed out, and then had to walk away for a few minutes, and while I was gone my connection went bye-bye. Basics were, probably a bad element, TURN THE POWER OFF before you start working on it, drain the heater through the drain valve using a garden hose, unhook wires, use large socket to remove element, put in new element, rewire, turn water on and check for leaks for at least 1/2 hour, turn power back on.

As usual, havasu has better plumbing advice, delivered quicker, than I do.
But an inferior spell checker.

[Left-is-Hot]

havasu, It's a gas heater. At least 10 1/2 years old.
Have not drained any sediment. I will look into that.

[havasu]

Sorry for the brief message but I'm at lake Havasu and typing on a droid. Bump to top puts the question back on top so others will help you faster. If draining sediment does not help you, you may need to purchase a rod, which in your case is probably rotten, which is a good indicator you may have to bite the bullet and buy a new water heater. Please keep us informed!

And with over ten years of usage, it has given you a good life and time to replace it if draining/refilling doesn't help.

[Left-is-Hot]

So a rod isn't a "field replaceable" item huh? What exactly does a "rod" do?

What is this "sediment" made up of? Kind of like the rust that accumulates inside pipes? Dark red / black colored stuff?

And does that somehow interfere with the thermostat's ability to gauge the temperature inside there?

I thought water heaters lasted longer. Oh well.

I repair computers, so a faulty water heater is like a puzzle that I have to fix otherwise I feel like I failed!

[havasu]

On the cold water inlet is a long metal rod, which shoves the cold water to the bottom of the tank. It is also sacrificial, like a boat anode, allowing dissimilar metals to eat up the rod, and protecting your water heater. If this rod has done its job, your water might not mix properly. This sounds like your problem. As said earlier, you may have luck cleaning the sediment and replacing the rod, but normal life for the heater is 6 to 10 years, so yours has had a good like. New water heaters are more energy efficient, and save money in the long run, with less chances that your seams are beginning to rot, which is a bad thing.

[Left-is-Hot]

with less chances that your seams are beginning to rot, which is a bad thing.

What are "seams"? Something that runs throughout the copper piping system throughout the house?