View exterior work is fine, the structure is compact, the board core is dark black (full copper plate core is better), the vacuum tube whether dark blue or black, the rear mirror as a mirror, if the answer is yes, indicating that visual qualified. In addition, we observed did not buy the accessories portfolio traces confirm this is not difficult to see the main components of the brand identity on the line. If the pressure also check safety valve, intake valve are complete, whether the quality. And later check the product number, no long-term does not disappear with or solar power air conditioners the production of standard product specifications and warranty certificate, of course, can not be ignored.

Check the water tank insulation thickness. Sheet insulation layer thickness should be ≥ 30mm polyurethane overall foam insulation best. The polyurethane foam is yellow, a bit like a sponge, foam has a uniform pore hand squeeze to have a certain flexibility, but the insulation layer is too soft measuring instructions of its less dense, is not conducive to insulation. Vacuum tube water heater insulation layer and the insulating layer thickness should be ≥ 45mm, 50 ~ 55mm is better, remove a vacuum tube with your finger in the tank hole to feel the thickness of the insulation layer can also be used to measuring tape. Since then, the hole can also check the liner thickness, can touch the edge of the hole by hand, feel or compare liner thickness, where the liner thickness ≤ 0.4mm on the life of a problem. Standard tank can open the end cap has a cleaning hand-holes, a comprehensive inspection of the insulation status.

The vacuum tube is the core component of the solar water heater. In addition to visual inspection, but also hand to knock, and weigh. Hand to seize the vacuum tube, knocked one hand with the back of the hand joints, listen to metal-like sound, and if so, that good material and vacuum. If the conditions can also be said that said the weight of the vacuum tube, φ47mm pipe length 1.5m weight of each should be about 1.5kg, the more light indicates that the vacuum tube the worse quality. When choosing a vacuum tube water solar powered air conditioning, do not have to care about the size of the vacuum tube, In theory, the collector effect and the size of the vacuum tube.