A torch ignitor system comprising: a torch wall defining a combustion chamber therein with a flame outlet passing out of the torch wall downstream of the combustion chamber; a fuel nozzle mounted to the torch wall to issue fuel into the combustion chamber; an ignitor mounted to the torch wall, extending into the combustion chamber to ignite fuel issued from the fuel nozzle; and a cooling passage in thermal communication with the ignitor for cooling the ignitor with fluid passing through the cooling passage; wherein the cooling passage is defined between a fuel inlet and a fuel outlet, wherein the fuel inlet is configured to introduce fuel from a fuel source into the cooling passage, and wherein the fuel outlet is in fluid communication with the fuel nozzle to supply fuel to the fuel nozzle; characterized in that the ignitor is one of a plurality of ignitors each mounted to the torch wall, extending into the combustion chamber, wherein the cooling passage is in thermal communication with each of the ignitors in the plurality of ignitors for cooling the ignitors with fluid passing through the cooling passage; wherein the cooling passage includes a respective coil section that is coiled along a helical path around each ignitor in the plurality of ignitors; wherein each ignitor in the plurality of ignitors extends from outside the combustion chamber, through the torch wall, and into the combustion chamber, wherein the respective coil section coils around a respective portion of each ignitor in the plurality of ignitors that is outside the combustion chamber; and wherein the coil sections are connected in series with one another so the cooling passage is in thermal communication with all of the ignitors in the plurality of ignitors, wherein a respective transit portion of the cooling passage connects between sequentially adjacent coil sections. a torch wall defining a combustion chamber therein with a flame outlet passing out of the torch wall downstream of the combustion chamber; a fuel nozzle mounted to the torch wall to issue fuel into the combustion chamber; an ignitor mounted to the torch wall, extending into the combustion chamber to ignite fuel issued from the fuel nozzle; and a cooling passage in thermal communication with the ignitor for cooling the ignitor with fluid passing through the cooling passage; wherein the cooling passage is defined between a fuel inlet and a fuel outlet, wherein the fuel inlet is configured to introduce fuel from a fuel source into the cooling passage, and wherein the fuel outlet is in fluid communication with the fuel nozzle to supply fuel to the fuel nozzle; characterized in that the ignitor is one of a plurality of ignitors each mounted to the torch wall, extending into the combustion chamber, wherein the cooling passage is in thermal communication with each of the ignitors in the plurality of ignitors for cooling the ignitors with fluid passing through the cooling passage; wherein the cooling passage includes a respective coil section that is coiled along a helical path around each ignitor in the plurality of ignitors; wherein each ignitor in the plurality of ignitors extends from outside the combustion chamber, through the torch wall, and into the combustion chamber, wherein the respective coil section coils around a respective portion of each ignitor in the plurality of ignitors that is outside the combustion chamber; and wherein the coil sections are connected in series with one another so the cooling passage is in thermal communication with all of the ignitors in the plurality of ignitors, wherein a respective transit portion of the cooling passage connects between sequentially adjacent coil sections.