I have a reliance 606 electric water heater. This is my problem. The water gets unbearably hot then I have to reset the reset button on the water heater. I am thinking that I need to replace the heating elements.

You water heater most likely has a shorted heating coil, don't run it like this, call a service technician.

short in the wiring bypassing the thermostats
get an electrician in as the fault is serious enough to need it resetting

Reliance Water Heater Literature ' Owner's Manuals ...

www.reliancewaterheaters.com/resources/instruction-manuals

Welcome to the Reliance Water Heaters Owner's Manual and Installation ... 9 40 EKRT - 40 Gallon Tall Self-Cleaning Electric Water Heater - 9 Year Warranty . ..... 10 50 DHPST - 50 Gallon Electric Heat Pump Water Heater - 10 Year Warranty .

How to light the pilot on a Reliance 606 water heater ...

? 3:27
https://www.youtube.com/watch?v=VU2PsFVd2ug
Jul 12, 2011 - Uploaded by kilroywashere123
How to light the pilot on a Reliance 606 water heater ... How to fixwater heater, will not stay lit - sealed combustion no hot water - Duration: ...

Reliance Water Heaters - Consumer Affairs

www.consumeraffairs.com > Homeowners > Bath & Plumbing

Rating: 1.6 - ‎84 votes
I purchased a Reliance 606 water heater in 2010. ... That they don't TELL you there's areset button or that I'm having conspiracy thoughts ... After several attempts, I was able to relight it. ... It's heading to the junk pile and I will purchase a new reliable (NotReliance) ... Checked breaker and changed breaker still no hot water!

http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

Replace both thermostats. One or the other is sticking, and there is no way to test which one is bad... since test unsticks a stuck thermostat

Gene

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

No reset button.
The gas control valve is the thermostat
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

Intellivent gas control can be reset, and Honeywell can be reset under some circumstances.
Otherwise, bad thermostat means replace gas control valve

Gene

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

It is probably the thermostat. I would suggest replacing that next.

If it was working and recently stopped working, the heating element that heats the water probably went bad, no longer functioning. Check to make sure that there is or is not a reset button, and if there is, press and reset the heater. It's not difficult to remove the old heater element and replace it, but make sure the circuit breaker power to the water heater is off when you remove it. Take it to a water heating supply store, or large hardware store with the Brand and model number of your water heater (Reliance RELIANCE ELECTRIC WATER HEATER,model 606 ) to buy another one.

ECO reset button trips for several reasons.

1) Easiest thing without testing, is replace both thermostats.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

2) If problem persists, then test elements.
http://waterheatertimer.org/How-to-test-water-heater-element.html

3) If problem continues, do full troubleshoot
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

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 water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

I wrote a page for changing water heater thermostat.
The photos take you through step-by-step
I recommend replacing both upper and lower thermostats so it eliminates thermostats as possible cause if water heater keeps overheating.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

The Reliance 606 manual shows your water heater uses generic upper and lower thermostats from hardware store.
http://www.reliancewaterheaters.com/lit/om/manuals/185761-000.pdf

Likely the thermostat will solve the problem:
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

needs new thermostat(s) If the whole tank is heating( next time it trips, before using any hot water check the lower tank thru the lower element access(breaker off) If the lower tank is hot-you need a new lower thermostat. if just the upper part of the tank is heating -you need an upper thermostat.