1. Look at the quality of the vacuum tube. The vacuum tube is a key part of the water heater. When purchasing, you should carefully observe the glass tube coating inside the vacuum tube. , dark blue or dark gray. A good quality coating has a uniform color, no scratches, peeling or peeling on the film, there are no stones on the glass and the backings are placed correctly and will not come off.
2. Look at the insulation layer and the covering. The processing technology has a layer of insulation material between the outer shell and the tank liner of the solar water heater, which plays a very critical role in insulating hot water. . It is made of polyurethane. The lifespan of insulating materials can reach more than 10 years. The inner tank is where the hot water is stored and its thickness is approximately 0.5mm.
3. Look at the support design. The bracket supports the frame of thecollector and the insulated water tank. It must have a solid structure, high stability, wind and snow resistance, aging resistance and no rust. The material is usually stainless steel, aluminum alloy or powder-coated steel.
4. Select the water tank capacity. Generally, domestic bathing water is low: if domestic water includes cooking, the total water consumption can be estimated based on the per capita water consumption of 40L; The temperature of domestic solar water heaters in winter is generally calculated at 50 to 60 degrees, converted to the water capacity of the water heater. The actual purchasing decision depends on the condition of the water heater.
How to identify the quality of solar water heater products? Usually, it needs to be tested by instruments to see if it meets national standards. If you rely only on experienceto identify, you should pay attention to the following aspects:
1. When purchasing products, you should understand whether the water heater, collector, pipe interface and plate core have been subjected to stress. pressure test and test before leaving the factory. Leakage inspection should also comprehensively consider product types, materials and consumers' requirements, such as selecting products of different prices according to their own economic conditions, choosing water heaters of different volumes depending on the number. family members, antifreeze problems in the north, and advanced hotels need to consider whether the product can be used 24 hours a day, etc.
2. To understand the technical performance, it is mainly the average daily efficiency and the average heat loss coefficient. At present, many people thinkt erroneously that the higher the water temperature in the water tank, the better the thermal performance. Indeed, the temperature of the water cannot indicate the quality of the product. Water temperature, sunshine intensity, sunshine duration, water capacity, lighting area and initial water temperature are all related, so the most scientific method is to examine the thermal efficiency and heat loss coefficient. At present, the average daily efficiency of vacuum tube hot water pipes should be above 40%, and the heat loss coefficient should be less than 2℃/square meter.