Pilot will not stay lited - Reliance Water Heater #6-30-YORT 30GAL NAT GasWTR Heater

usually it is the thermocouple. easy to replace. it the part that the pilot lite heats so that the gas valve will allow the gas to flow. common issue. most hardware store has the part. and the part is pretty universal. youtube has a few good videos. appliance parts stores also stock item. good luck.

Maybe, or maybe the FV system tripped.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html
http://waterheatertimer.org/How-to-test-water-heater-thermocouple.html

If you have error-code type gas control, then you have thermophile and not thermocouple
Troubleshoot 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

Clean air intake, clean combustion parts, check gas pressure, review draft, replace gas control valve ...
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#pilot
http://www.thetankatwaterheaterrescue.com/forums/forum3/

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

It depends on many factors, including brand, type of heater, age, gas pressure, maintenance, venting, proper installation of thermocouple, bad thermocouple, air intake cleaning, if the flame is clear blue etc.
Copy following link to read more:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#pilot

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

I looked up this unit for you and found out it is a hot water system. She needs to get to the main gas valve to light the pilot. This unit has what is called a thermocouple on it that keeps the pilot on, even when the boiler shuts down. Its just a matter of lighting the pilot light. There should be a metal plate with the directions on it at the gas valve to lite it. You will have a knob, more then likely red or black in color on top of the valve. It will say on, off, and pilot. It should be in the on position now. Turn it to pilot. Have some matches with you and a flashlight if you can. You will need to look back into the burner area to where your pilot light will be. The thermocouple is a copper colored tubing that runs right back to the pilot, as it has to get hot from the pilot flame to work. To start, depending on how far back you have to reach with the match, you may need to use a piece of solid cardboard rolled up, a small piece to light it and reach in. Turn the knob to pilot. Now, push down on the knob and hold it down. This lets gas get back to the pilot, so you must keep it down and light it at the same time. Once it is lite, you have to hold it down for at least a minute. Slowly release it, very slow. The flame should then stay on. Once it is on, turn the gas knob to on. With the thermostat set to come on, it will fire up and heat the water. If the pilot will not stay lite after you hold it down for 1 minute, and keeps going out, the thermocouple will need to be replaced. It is the copper line that screws into the gas valve and goes back to the pilot. You can get them at any hardware store for around $6.00. Maybe you can help her install it. It is very simple to do. I believe the pilot just blew out and she will need to light it. Just follow what I have told you, and she will get it lite. Good Luck to you.

When you light the pilot lite you have to hold the button down until it gets the element hot enough to stay lit. If you hold down the button and lite the pilot and let it go right away it will go out. What to do is hold down the button and lite the pilot and continue to hold the buttn down for about 45 seconds to a minute then let it up very slowly and you will see if it is going to go out by the flame getting smaller as you let up on the button. If it does start to get smaller conitnue to hold it again for a few seconds and repeat the process of letting it up slowly. when the control element gets to the right temperature it will stay lit then turn your valve to "ON" and the fire will start up and continue to heat the water.

At the controls there should be a knob that says " Pilot"... "ON" Turn the knob to pilot and hold it down while lighting the pilot lite. Keep holding it down until it gets warm enough that when you leave it up the pilot stays on. Once the pilot lite stays on on it's own turn it to on.

the gas is not coming out of the burner, probably due to rust clogging the holes.

It sounds like your main valve. The diaphram may be loose fitting or it has a small leak.

By controler I am guessing you mean gas valve? The next step, and I am not sure the water heater age rates this ,is to replace the gas valve.