Seven SS 150L Low Pressure Stainless Steel Solar Water Heater

150L Low Pressure Solar Water Heater

• Optimal Capacity: Designed to provide ample hot water for a small to medium-sized family (approximately 4-5 members), ideal for daily bathing and kitchen use .

• Superior Material Quality: Features a food-grade SUS304-2B Stainless Steel inner tank, ensuring superior corrosion resistance, hygiene, and longevity compared to standard steel tanks .

• Low Pressure System: Specifically designed for non-pressurized (gravity-fed) applications. The maximum working pressure is typically around 0.05Mpa (approx. 7.25 PSI) , making it compatible with header tanks and areas with unstable water pressure .

• High-Efficiency Technology: Utilizes advanced evacuated glass tubes with three-target coating for maximum solar absorption (up to 96%) and minimal heat loss, ensuring hot water even on cloudy days .

• Excellent Insulation: The tank is insulated with high-density polyurethane foam to keep water hot overnight, minimizing temperature drop .

• Durable Outer Frame: The frame is made from powder-coated or galvanized steel, providing robust support and resistance to rust and weather elements .

• Brand Assurance: Seven SS products are built with precision and come with a standard warranty on the tank and tubes (conditions apply) .

150L Low Pressure Solar Water HeaterComplete Technical Specifications

To ensure you have all the details for installation and product listings, here are the in-depth technical specifications for the Seven SS 150L model.

Tank Specifications

• Inner Tank Material: SUS304-2B Stainless Steel (Food Grade)

• Inner Tank Thickness: 0.31mm – 0.5mm

• Outer Tank Material: Corrosion-resistant colored steel or pre-coated zinc wrap

• Insulation Layer: 50-65mm high-density polyurethane foam

• Tank Capacity: 150 Liters (Total storage)

• Inlet/Outlet Hole Size: Male G 1/2″ or 3/4″ (Standard plumbing connections)

Collector Tube Specifications

• Tube Type: Three-target evacuated glass vacuum tubes

• Tube Dimensions: Standard 58mm (diameter) x 1800mm (length)

• Number of Tubes: Typically 15 to 18 tubes (depending on the specific model configuration) .

• Glass Material: High borosilicate glass (3.3)

• Absorption Rate: 93% – 96% (AM1.5)

• Emission Ratio: 4% – 6% (at 80°C)

System Specifications

• System Type: Direct (open circuit) / Non-Pressurized (Low Pressure)

• Maximum Pressure: 0.05 Mpa

• Connections: 5 ports typically located on the tank (Air Vent, Inlet, Outlet, Electric Heater Backup, and Temperature Sensor/Solar Loop) .

• Installation Type: Suitable for pitched or flat roofs with a sturdy powder-coated frame .

• Full System Weight (approx.): 190 kg – 240 kg (when filled with water) .

Installation Guide & Best Practices for the 150L Low Pressure Solar Water Heater

Proper installation is key to the performance and longevity of your Seven SS solar water heater. Follow these step-by-step instructions or ensure your installer adheres to these standards.

Step 1: Site Selection & Mounting

1. Orientation: In the Northern Hemisphere, the collector should face South. In the Southern Hemisphere, face North. The ideal orientation is typically within 10°-15° of true North/South to maximize sun exposure .

2. Shading: Ensure the location is free from shading by trees, buildings, or other obstructions throughout the day.

3. Roof Structure: The mounting surface must be capable of supporting the heavy weight of a full system (approx. 240kg). Use concrete bricks or reinforced stands if necessary .

4. Fixing the Frame: Securely fix the frame feet to the roof or foundation using expansion bolts. In windy areas, use steel wires to firmly fasten the tank and frame to prevent movement .

Step 2: Tank and Tube Assembly

1. Position Tank: Carefully place the stainless steel tank onto the frame cradle. Ensure the tank is perfectly level by using waterproof cushions to adjust the frame height. All feet must contact the surface evenly to avoid frame deformation .

2. Prepare Tubes: Clean the glass end of the vacuum tubes with water or detergent to lubricate the seal.

3. Insert Tubes: Gently insert the tubes into the tank’s rubber seals (silicon rings) using a firm, twisting motion. The force must be directed along the axis of the tube to prevent breakage .

4. Secure Tubes: Place the bottom of the tubes into the tail support holder on the frame and push the insulation ring up to the tank for a tight seal.

Step 3: Plumbing Connections

1. Piping: Use standard galvanized or copper pipes for connection. For unvented or specific safety requirements, copper pipe is highly recommended .

2. Safety Valves (Crucial for Low Pressure): Because this is a low-pressure system, it must never be connected directly to high-pressure mains water without a control valve.

   • Install a Pressure Control Valve (set to 400kPa or as per local codes) on the inlet .

   • Install Vacuum Breakers on the inlet and outlet to prevent tank collapse or siphonage .

   • An Assistant Tank (small header tank) is often required to regulate the water supply and maintain consistent pressure.

3. Sealing: Use Teflon tape or suitable thread sealer on all threaded connections to prevent leaks. Use compression fittings on cylinder connections where specified .

Step 4: Final Checks

1. Fill the System: Ensure the system is filled with water before exposing the tubes to the sun. Filling an empty tank on a sunny day can damage the tubes due to thermal shock.

2. Check for Leaks: Inspect all seals, pipe joints, and tank connections.

3. Electrical Backup (Optional): If the model includes an electric backup element, ensure the tank is full of water before switching on the power to prevent burning out the element .

4. Temperature & Pressure Relief: Ensure the T&P relief valve discharge pipe is routed to a safe, visible drain location and is not blocked .

Maintenance Tips

• Tube Cleaning: Clean the glass tubes periodically (every 6-12 months) to remove dust and dirt that can block solar radiation.

• Valve Check: Manually operate the pressure relief valve at least once a year to ensure it is not stuck. Caution: The water discharged may be very hot. .

• Visual Inspection: Regularly check for any condensation inside tubes (a sign of a broken vacuum) or leaks from the tank connections.

Why Choose Seven SS?

Choosing Seven SS means opting for reliability. Our 150L low-pressure system combines the corrosion resistance of stainless steel with the high efficiency of modern vacuum tube technology. It is a cost-effective, “fit-and-forget” solution to your hot water needs.