If the pilot light is on, the heater should come on by itself. If the pilot light is off then it has to be lit. If it will not stay on, the thermocouple is bad.
You don't, DVD burners come on desktop computers/laptops
To me it sounds like your pilot light on the fireplace is out. That could happen from a strong wind coming down the chimney or a strong breeze in the house from a fan. Check your pilot light and be sure to have the gas off before lighting the pilot light if it is out.
See if the holes in the metal grid are blocked so that the flames can not come up.
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.
from minerals and are separated in distillation.
The thermocouple is bad. The thermocouple is the small metal tube that sits in the pilot light flame and runs to the control valve. The thermocouple generates a very small electrical current that keeps the gas valve open. They go bad regularly. **** I would have to say to check to make sure the valve is not in the "Pilot" position. If it is then turn it to the "On' position. If it still isn't working then you may have a bad Gas Control Valve. If the thermocouple was bad the pilot light would not stay lit. If the pilot light stay lit, it is doing what it is supossed to do.
Thermostat setting may be same as room temperature ,therefore boiler will not ignite
If the light has come on the system has a problem and set a code(s). Most auto parts stores can read the code(s) and tell you what went wrong.
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.
No, not all computers come with DVD burners built into them. Although they are more common in computers today, they are sometimes an upgrade that must be purchased with a computer.
Bad thermo,replace. The thermo senses that the pilot is lit and opens gas valve,also could be bad or blocked gas valve.