FIRE GOES OUT AFTER AWHILE

Check and clean, tighten all grounds .

Never play around with Gas call Your gas repair out.

All appearances - No fuel to ignite!
evrything else looks good, proper gas pressure, proper volts at igniter, etc - it should ignite! If fuel present, heater should Fire!
make sure all valves are open.
Gas valve is ON
AND purge any air from gas line.
IMPORTANT ****. If you bled gas line, don't try to ignite for a few minutes. Allow gas to dissipate first, use a fan to help.

If you're using propane gas, the banging noise you hear is air in the gas line, which means either your tank is empty or the the tank regulator is frozen (if it's ,below freezing in your area). If the tank regulator is frozen, soak a bath towel in hot water and quickly place it around the regulator. It should thaw fairly quickly and the gas will start flowing again. However, you may need to purge the air out of the gas line to gas log burner. Rather than using the electronic ignitor, do it manually, until you smell gas, left off the control knob and wait 5 minutes and then try lighting the pilot electronically.

If you're using Natural Gas, it may still be a pressure problem to the burner. You'll need to have that professionally checked.

Hope this helped to solve your problem.

Sometimes the thermostat wire (not sure of the technical name) gets oxidized and can't sense the heat (it's there as a safety measure so that when the pilot light goes out, the gas shuts off). If it isn't to hard to get to, sometimes you can use some aluminum foil to clean the wire so that it senses the heat of the pilot light flame. Make sure the main unit is off, and let the unit sit for awhile to make sure there is no residual gas hanging around. If this doesn't work, you might have to get a specialist out to replace that piece. Hope this helps.

If you hear it sparking, verify the spark is happening INSIDE the combustion area and not shorting out at the ignition module. Also verify you actually have gas available and the gas valve is turned on...

Try vacuuming out the intake and exhaust of the burner to remove any lint or other debris. If no help, the main burner may need to be replaced.

i have had a legend vantage slide control gas fire for about 5 years.this problem is i believe a blocked oxy get which is a failsafe device to prevent a gas leak.can be remedied easily by a gas safe engineer.

you have a clogged pilot orifice you will need to remove from valve and apply pressure to it to clear. compressed air with a fitting to make sure it goes thru the tube

If the pilot stays lit when it goes out, it's something else. If the pilot goes out as well, replace the thermocouple.