The water in the tank is used as the heat transfer medium, rather than using it directly. The obvious advantage is with water supplier, which can supply cold water into the tank automatically; It can be connected to pressurized system.

Solar water heater Feature: 

1) Designed to accept mains pressure cold water
2) Copper coil heat exchanger can be used as part of a closed or open loop system, providing heating to a main hot water tank
3) Freezing is of minimal concern for SFD series
4) Reliable, efficient, twin-glass solar tubes
5) Superior heat preservation with 50 - 65mm polyurethane tank insulation
6) Outer tank material: stainless steel plate or powder coated color steel sheet
7) Inner tank material:
a) 0.5mm thick SUS304 food grade stainless steel plate 
b) High purity copper for the heat exchanger coil 
8) Frame material: 1.2mm thick all stainless steel 
9) Collectors may be connected in series to increase water heating capacity 
10) Easy plug-in installation 11)Water supplier: supply the slowly vaporizing water in the tank in time 
12) Ideal for commercial solar water heating applications 

SFD series Solar water heaters Specifications:

SFDseries Solar water heaters Package and Size:

Package: Solar Water tank, Solar Standing Frames, Solar tubes are separately packed in one carton. Cartons can be loaded into container directly.

Optional Accessories for SFD series Solar Water Heaters:

Item		Name	Describe
1		Water Supplier	SFO180D Dai. 180mm Length 250mm 3.9 Liters  Function:  Used to fill the water into big water tank automatically, more convenience.
2		Solar Controller	Display panel with Connection box Temperature sensor and water level sensor for water tank Electromagnetic valve for filling water 220V 50HZ/110V 60HZ If you choose this, you do not need water supplier
3		Magnesium Rod	For the solar water heater with SFVA5818 glass vacuum tubes, length: 200mm Function: Improve the water quality and prolong the life time of watet tank
4		Electric Heater	Voltage/Frequency: 220V 50HZ / 1KW-2.5KW Screw Plug----3/4 inch Function: Backup heating in rainy or cloudy days
5		Ball Valve	Function: As a switch in system
6		Constant Temperature Mixing Valve	Function: It is used to mix cold water and hot water of system, to avoid the potential danger when the outlet hot water temperature is too high. You could set the temperature by yourself, bring you more comfortable bath in warm water, and energy saving.