The　heat　pump　system　utilizes　shallow　geothermal　energy　in　the　coastal　areas,　which　not　only　uses　clean　energy　but　also　contributes　to　energy　conservation　and　environmental　protection.　This　paper　studies　the　performance　of　a　heat　pump　system　applied　a　capillary　heat　exchanger　as　an　energy　collection　device.　The　numerical　performance　of　capillary　heat　pump　showed　a　good　agreement　with　the　experimental　data　in　the　winter　heating　mode　and　the　summer　cooling　mode.　It　was　concluded　that　the　COP　of　the　heat　pump　unit　using　the　capillary　heat　exchanger　was　5.32　in　winter　and　4.32　in　summer.　©　The　Authors,　published　by　EDP　Sciences　2018.