Sounds like you need a thermocouple.
Yes
The water continues to run into and out of the water heater. There is just no flame to heat it up.
have you checked to see that gas is getting to the valve if it is the pilot could be stopped up pull it try to clean it soak in spray carb cleaner ect. blow out with compressed air or replace with new oneAnswerTake the tubing loose from the pilot assembly and depress the pilot valve on the gas valve to see if gas is getting to the assembly. If it is, you have a clogged pilot orifice; take a thin piece of wire and clean it out. If you have no gas getting to the orifice, you still have a bad gas valve or your gas is not turned on.
If it is windy outside, you may be getting just enough of a breeze to blow out the pilot light -even though the covers are shut. My heater is in the garage, and even w/ the garage door shut and the covers on the heater shut, very windy weather can still cause enough of a draft to blow out the pilot. You could try to find something to block drafts around the heater such as a hot water heater blanket.
The thermocouple is usually the first thing to change. It controls the valve and the spark ignition is just to light the pilot.
Turn knob to PILOT, press button down and light the pilot; hold button down for 60 seconds and release - pilot should remain lit; turn knob to ON. If pilot does not remain lit, turn knob to OFF, wait 5 minutes and try again, If pilot still will not remain lit, replace the thermocoupler.
it will heat as long as the gas is on and your pilot is still lit, you would have to call your gas company to turn it off.
Check for a heater flow valve in the heater hose they can rust shut easily it is a valve in the heater hose that opens when you turn on the heat and shuts when its not in use, if not then probably the core is plugged a radiator flush might help but you may need to have it cleaned and repaired.
The pilot setting will heat the water a few degrees. A gas water heater will have a thermal rating in BTU of 30,000 to 80,000. The pilot light by itself will have about 1,000 BTU. Operating overnight with no water movement and a well-insulated tank, you will observe a temperature rise but certainly not enough for clothes washing, dishwashers, or showers.
Pilot light alone will not produce enough heat to damage the tank, but the main burner will destroy the tank and possibly start a fire. Why would anyone want to leave the pilot light on an empty tank?
A number of problems can cause a swimming pool heater not to work. The most common I have found is lack of water flow. A heater needs a certain amount of water flowing through it to work correctly. The next most common problem is due to the pilot not lighting or remaining lit. This is usually due to the pilot generator not working. When you light a pilot light and have to hold it for a length of time before releasing the button you are allowing the pilot generator to heat up and then stay open to keep the pilot lit. Usually you need a licensed person to do work with changing items on a gas unit. The thermostat can be a problem for any water heater. Most of the heaters I have worked on were gas. If you have an electric heater waterflow still needs to be checked and the electrical connections can become corroded in the presence of chemically treated pool water.
It depends on how the fan control circuit is wired. If you have a Fan On/Auto switch, yes it will blow cold air if the switch is put to On.