圆形水箱是比较常见的一种水箱，有保温水箱和冷水箱2种，空气能热水工程使用的一般都是保温水箱，有时也会配冷水箱。圆形水箱有3种规格的，一种外面（外胆）用的是304不锈钢，里面（内胆）用的也是304不锈钢；第二种是外胆用的201不锈钢，内胆用的是304不锈钢；第三种是外胆和内胆都是用的201不锈钢。从材质上我们就能看出他们的不同之处，在热水工程中到底是用的哪一种材质水箱也是要根据客户的需求来选择的。
Circular water tank is a common type of water tank, with two types of heat preservation water tank and cold water tank. Generally, heat preservation water tank is used in air energy hot water project, and sometimes it is equipped with cold water tank. There are three specifications for the round water tank, one is 304 stainless steel for the outer tank and the other is 304 stainless steel for the inner tank; the second is 201 stainless steel for the outer tank and 304 stainless steel for the inner tank; the third is 201 stainless steel for both the outer tank and the inner tank. From the material, we can see the difference between them. In the hot water project, which kind of water tank is to be used is also to be selected according to the needs of customers.