Sucking solder without temperature control is no different than soldering without temperature control. If you are not good at spotting when the solder goes liquid or using a sort of solder which is difficult to see when it goes liquid than just apply solder as you heat it as you would if you were initially making the joint, solder touches the pin and not the iron's tip, when the solder starts to flow put down the solder and grab the sucker, suck. No need to rush when getting the sucker, you have a second or two still before the entire joint has gone liquid and a few seconds after that before you are at risk of overheating assuming you are using a properly sized iron for the job.