This question is not specific enough for a good answer. What is the appliance? A furnace? A cooktop burner? An oven?
The first thing to check would be the igniter, which is what typically "lights" the gas coming from the valve.
You can check an igniter with a simple continuity test using a test meter.
If the pilot is lit, then there is no igniter, or the igniter lites the pilot, so if the pilot
is lit how could it be the igniter.
Bad thermocouple, this tells the gas valve that the pilot light is lit, if the gas valve does not know the pilot is lit it will not allow gas to come out of the valve, this is a safety feature so your unit does not blow up.
i have a model 125u19 payne furnace i move the thermostat but nothing comes on in the furnace and the pilot light is lit
Make sure gas is on and shut offs are open Turn gas valve to PILOT position Push knob down and light pilot HOLD knob down for aprox. 30sec-1min Slowly release knob Pilot should stay light (if not troubleshoot) Turn know to ON position Adjust thermostat to desired position
To turn on the pilot light on a gas appliance, locate the pilot light button or knob and turn it to the "pilot" position. Then, press and hold the button while using a long lighter to ignite the pilot light. Keep holding the button for about 30 seconds to allow the pilot light to stay lit. If the pilot light goes out, repeat the process.
To turn on a pilot light, locate the gas valve and pilot light knob on the appliance. Turn the gas valve to the "pilot" position and press down on the pilot light knob while using a lighter or match to ignite the pilot flame. Hold the knob down for a few seconds to allow the pilot light to stay lit, then release the knob.
You may have the gas valve selected to pilot. Turn the knob from PILOT to ON. It should fire immediately. If you have a wall mounted thermostat, make sure it's set to a point that calls for heat.
To turn on the pilot light for your water heater, locate the pilot light assembly near the bottom of the water heater. Turn the gas control knob to the "pilot" setting and hold it down. While holding the knob down, use a long lighter to ignite the pilot light. Once the pilot light is lit, continue holding the knob down for about 30 seconds before releasing it. If the pilot light stays lit, turn the gas control knob to the "on" position to start the water heater.
To turn on the water heater pilot, locate the pilot light button or knob on the water heater. Turn the knob to the "pilot" setting and hold it down. While holding the knob down, use a long lighter to ignite the pilot light. Once the pilot light is lit, continue holding the knob down for about a minute before releasing it. This should successfully turn on the water heater pilot.
You may have a faulty thermostat that isn't closing when heat is called for. Also a faulty gas valve could be the problem. Also, be sure that the gas valve isn't in the "Pilot" position. This is the position you turn the gas valve to when lighting thepilot light. If your pilot light isn't staying on after being lit, then you may have a bad thermocouple.
To turn the pilot light on, locate the pilot light button or knob on your appliance. Hold the button down and simultaneously press the ignition button to spark the flame. Keep holding the pilot light button for a few seconds to allow the flame to ignite and stay on.
To turn on the water heater pilot light, locate the pilot light assembly near the bottom of the water heater. Turn the gas control knob to the "pilot" setting and press it down. While holding the knob down, use a long lighter to ignite the pilot light. Keep holding the knob down for about 30 seconds, then release it. If the pilot light stays lit, turn the gas control knob to the "on" position. If it doesn't stay lit, repeat the process.
To turn on the pilot light on your water heater, locate the pilot light assembly near the bottom of the water heater. Turn the gas control knob to the "pilot" setting and hold it down. While holding the knob down, use a long lighter to ignite the pilot light. Keep holding the knob down for about 30 seconds, then release it. If the pilot light stays lit, turn the gas control knob to the "on" position. If it doesn't stay lit, repeat the process.
Have you rotated the gas valve knob to "run". Have you turned up the thermostat? Is the pump running? No pump water flow - no heat -- no filtration. Is the filter clean? When was the last time you cleaned the filter? Ken