gas combi boiler Packaging & Delivery :1) Packing Detail: 1pcs 5 layers carton with poly bag&foam.2) Deliery Detail: Around 30days after comfirm the order.Techology Parameter for our Wall Mounted Gas Boiler: GB-S350-AGB-S350-B GB-B01GB-Q7The heating system diagramof the wall mounted gas bolier: Product Features:1.Available models 18-24kw;2.EU style,elegant appearance;3.Digital LCD displayer;4.G20 water bypass valve (Italy);5.Exhausting fans are equipped with aluminum casing,Brass from japan.6.U.S. aerospace chips,dual-panel circuit board;7.It has automatic compensation functions for indoor/outdoor temperature;8.Energy saved in heating supply,Japanese Omron pressure switch increases its reliability;9.Oxygen-free copper for the heat exchangers, efficiency more than 92%;10.Smart anti-freezing function when the water temperature is lower than 5-7degrees.Product Inside Showing : Our Test Room Photo: