SP-80 is an 80-liter (20 gallon) expansion vessel designed for closed-loop solar hot water systems. It effectively manages temperature fluctuations to maintain safe pressure levels and protect the system from excessive variations.
Built for extreme environments, the tank supports up to 10 bar (150 psi) and 130°C (266°F). It is factory pre-charged to 3.5 bar (50 psi) with 100% nitrogen gas to ensure stable performance and prevent thermal pressure spikes.
With a 43.2 cm diameter and a heavy-duty base, the SP-80 is ideal for robust commercial and large-scale residential solar setups. It provides high-capacity thermal liquid expansion management, offering a reliable and durable solution for demanding solar applications.
Product Overview
The SP-80 is an 80-liter (20 gallon) diaphragm expansion tank engineered for high-demand, commercial-scale solar thermal systems. It effectively regulates the significant expansion of water-glycol mixtures, preventing dangerous pressure spikes during collector stagnation and maintaining necessary system pressure when temperatures drop below freezing.
The tank is built with a heavy-duty cold-rolled carbon steel shell and a Red (RAL 3011) epoxy finish, providing a professional look with superior rust protection. Inside, a high-temperature resistant liner and a premium EPDM diaphragm (DIN 4807) work together to withstand the extreme thermal loads and chemical stress typical of large-volume solar loops.
Featuring a 1" 304 stainless steel connector, the CE and ISO9001 certified SP-80 ensures a lead-free and perfectly secure connection. This high-capacity vessel is the ideal choice for central solar heating plants or large industrial installations, offering a reliable, long-lasting solution for maintaining system safety and performance
Certification
Specifications and Technical Data
| Parameter | Value |
| Model Number | SP-80 |
| Total Tank Volume | 80 liters / 20 gallons |
| Diameter | 43.2 cm / 17.0 inch |
| Height | 70.0 cm / 27.6 inch |
| Net Weight (NW) | 12.7 kg / 28.0 lbs. |
| Gross Weight (GW) | 14.6 kg / 32.2 lbs. |
| Shipping Volume | 5.0 CUF |
| Operating Temperature | 1 - 130°C / 34 - 266°F |
| Factory Pre-charge | 3.5 bar | 50 psi |
| Max. Operating Pressure | 10 bar | 150 psi |
| Connection | 1” NPT / BSPT Stainless Steel |
| Liner Material | Polypropylene |
| Diaphragm Material | EPDM Rubber |
| Shell | Cold Rolled Carbon Steel |
| External Coating | Triple Grade Blue Paint |
| Pre-charge Gas | 100% Nitrogen |
Key Features & Design Advantages
How the Solar-Plus Pressure Tank Works
In closed-loop solar systems, the heat transfer fluid (often a water/glycol mix) expands significantly as it absorbs intense heat from solar collectors. The SP-80 manages this by storing the expanded fluid against the high-temperature EPDM rubber diaphragm, pushing against the nitrogen-filled air cushion. This safely relieves pressure. When the system cools—such as at night or in freezing temperatures—the nitrogen cushion forces the fluid back into the pipes, preventing the pressure from dropping dangerously low.
Key benefits
Typical Applications
Frequently Asked Question (FAQ)
A: Standard expansion tanks are not built to withstand the extreme temperatures generated by solar collectors. The SP-80 features a specialized high-temperature EPDM rubber diaphragm and liner capable of handling fluids up to 130°C (266°F) safely. Additionally, it is designed to manage water/glycol mixtures, which have a much higher coefficient of expansion than plain water.
A: The SP-80 is ideally sized for large 130-gallon solar water heaters.
A : Built to handle heavier fluid weight, the SP-80 is a floor-standing tank with an integrated base that measures 17.0 inches (43.2 cm) in diameter and 27.6 inches (70.0 cm) in height. It safely connects to your solar system using a highly durable, completely lead-free 1-inch 304 Stainless Steel connector.
Customized Colors & Packaging
We offer a wide range of customization options to match your exact needs - from custom colors to branded packaging and logo design.
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Downloads & Certification Links