In this study, a reliable and novel testing methodology is presented for the burst test of heat pipes developed for space applications. The test set up enables heat pipe to be tested at flight configuration. The target internal pressure of the heat pipe is achieved by increasing the temperature of the heat pipe and consequently the ammonia inside. The setup uses microphones, oxygen sensors and thermocouples for the accurate determination of the burst instant and temperature. Burst temperature and specific volume are then used in conjunction for the determination of the burst pressure via thermodynamic data for ammonia.