The pilot light has gone out on an old Vulcan gas wall heater. How do I turn it back on?

Clean pilot may be too small blow out with tube or air line , thermocouple not working try changing it

The igniter may be bad and needs replacing.

SEt to pilot, Push knob, push pezio ignighter until pilot lights, hold for 30 seconds. if it stays lit turn to on, if it doesn't stay lit, you have a bad thermocouple

you have air in the gas line , the pilot being so small it would take ages to come through , you need to purge the line to get the air out , se if you can undo the pilot line to pruge it

Most common cause of pilot light problems is air movement. If your space heater exhausts gas through the roof, ensure the cap is on and level. If not, outside air movement will blow out the pilot. If you do not have an exhaust gas duct, check that the unit is positioned so that it does not blow air back onto itself from walls, furniture, etc, and ensure no other devices that move air are aimed towards the unit. The unit also needs to be placed away from central ducting, including return vents.

Hope this helps!

Remove the access panel lower right hand side and locate the pilot light re-igintion push button. The instructions are pritnted on the back of the access panel.

Simply clean out the jet tube with a fine wire, the sound you hear is the gas blowing by the irregular edges, and swirling and not mixing and producing sound waves, (Bit like a flute) So, you need to clean the tube right out, and smooth off the end again, & sorta "Countersink", Flame the end too, at the end.use a very fine needle file, and make it look like new, that will sort your problem out. Then adjust so you have a good gas flow. Also check out it isn't blocked too.

Ck and ensure there is a pilot light.No pilot light, no gas.

Could be moisture in the gas supply line - get your gas fitter to purge the line at the meter.