Thermal　storage　technologies　are　widely　used　in　energy　conservation,　such　as　solar　energy　utilization,　balancing　electrical　power　load,　recovery　of　industry　waste　heat.　Most　of　the　PCMs　are　poor　heat　conduction　media,　the　main　thermal　resistances　in　the　heat　transfer　process　between　the　PCM　and　the　heat　transfer　medium　is　on　the　PCM　side.　In　this　paper,　an　electric　heating　unit　with　composite　phase-change　thermal　storage　technology　is　designed　and　manufactured.　The　practical　application　of　this　electric　heating　unit　is　space　heating,　so　docosane　is　chosen　as　the　PCM　in　our　experiment.　Considering　the　heat　transfer　process,　docosane　has　the　proper　temperature　of　melting　point　and　a　quite　high　latent　heat.　The　performance　of　the　unit　under　various　operation　modes　is　investigated　experimentally.　The　temperatures　of　latent　and　sensible　thermal　energy　storage　material　in　thermal　storage　process　are　measured　and　the　thermal　storage　capacity　is　calculated.　The　comparison　between　composite　phase-change　thermal　storage　method　and　sensible　thermal　storage　method　is　carried　out.　Copyright　©　2009　by　ASME.