Service HEater light is lit

sounds like temp sensor is bad

This is not normal. You have some sort of electrical short. Possible bad fuses, wiring, or board if its not showing a code on the display

Reliance water heater?
Thermocouple is good if the pilot stays lit continuously.

501 is older model. Unknown if this unit has FVIR protection and sealed combustion chamber or open air intake on front of unit.
http://waterheatertimer.org/pdf/Reliance-2006-Service-Handbook.pdf

With FVIR protection:
Get more fresh air to the unit.
Clean the flame arrestor screen.
Test and replace the thermocouple:
http://waterheatertimer.org/How-to-test-water-heater-thermocouple.html
Inspect and clean burner and combustion parts
Test gas pressure, bleed air out of gas line.
Replace gas control valve.
Test draft air by lighting match and see if smoke is pulled into the vent pipe at draft hood on top of tank.

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

Instructions for lighting Reliance 660 are located on the side of water heater just above the gas control valve.
If you are having other problems, read your product manual, or go to reliance for copy of manual, and read troubleshoot section:
http://www.reliancewaterheaters.com/lit/om.html

Unfortunately Rheem-Reliance does not post service manuals for their product. However other companies do post service manuals that might be similar to your water heater

Copy following link for troubleshoot service manual by type of gas control valve:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

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

Possibly the air intake located at bottom of heater needs to be cleaned with feather duster under water heater.
Read your product manual for steps.
Copy following link for general illustration.
http://waterheatertimer.org/images/State-select-air-intake-400.jpg
http://waterheatertimer.org/pdf/Flame-Arrestor-Screen-Cleaning.pdf
Other causes can be bad intellivent gas control valve, poor venting, hot attic, low gas pressure, dirty combustion parts, tripped FV system.
Copy following link for available intellivent troubleshoot resources:
The service manuals are large files and open slowly.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

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

Not enough information is given.
Add a comment any time.

Why did water heater turn off?
If water heater was exposed to flammable vapors like gasoline, paint thinner, paint, leaking gas line, etc, then the 'single use gas shut off' might have tripped.
If water heater is older and the burner parts never cleaned, then combustion chamber can experience overheating, and that can trigger 'single use shut off.'

Instructions for lighting water heater should be printed on side of heater.
Follow the instructions and see if water heater will light.
Then check if flame is clear blue. If flame is yellow-orange, then burner parts need to be cleaned.
If water heater will not light, then combustion parts may need to be cleaned, and air intake cleaned, and 'single use shut off' could also be tripped.

Also possible that gas control valve thermostat is bad.

Open following link to help identify gas valve and see illustrations and read information about cleaning combustion parts:
http://Waterheatertimer.org/How-to-install-gas-water-heater.html#troubleshoot
http://waterheatertimer.org/How-to-adjust-water-heater-temperature.html#intelli

Does the heater have a code displayed? Are any other lights lit on the display? If not you may have a blown fuse. Have turned the power button off and back on? After the heater shuts itself down you have to turn the power button off and back on to get it to do anything. If this doesn\'t help, let me know and give me some more details and I can help you out.

Niten\'s Heater Service on Facebook

Hi,

Here are a couple of tips that I wrote that tell you how to troubleshoot a Torpedo or Reddy heater...

Reddy Heater - Troubleshooting Torpedo Heaters

Torpedo Heater Pump Pressure Adjustment

heatman101


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This is normally caused by the thermocouple. This is the part the pilot light heats up to let the heater know the gas is on and the pilot light is lit. The heater will shut off if it thinks the pilot light is not lit for safety reasons. You will need to change the thermocouple for it to work again correctly.