Air　source　heat　pump　water　heaters　are　getting　commercial　applications　in　recent　years　in　south　China.　A　typical　model　of　such　product　was　tested　in　different　working　conditions.　ne　test　results　were　presented　and　discussed.　The　shortages　in　designs,　technical　barriers　and　their　influences　on　the　operations　and　reliabilities　were　analyzed　in　this　paper.　The　performances　and　the　operating　characters　of　the　heat　pump　water　pump　with　R417A　as　refrigerant　were　also　tested　and　compared　with　those　of　R22.　In　the　end,　the　development　and　the　application　potential　of　heat　pump　water　heaters　were　analyzed.