SP-24 is a 24-liter (6.0 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 highly compact diameter of 29.0 cm (11.4 inches) and a height of 40.7 cm (16.0 inches), this tank is ideal for point-of-use installations in solar setups, specifically supporting thermal liquid expansion for up to 100-gallon water heaters.
Product Overview
The SP-24 is a 24-liter (6.0 gallon) diaphragm expansion tank engineered to protect large-scale solar thermal systems. It effectively manages the high expansion rates of water-glycol mixtures, preventing dangerous pressure spikes during peak sun exposure and maintaining system balance when temperatures drop below freezing.
Built with a heavy-duty cold-rolled steel shell and a Red (RAL 3011) epoxy finish, this tank is designed for maximum durability and rust resistance. The interior features a specialized high-temperature liner and a premium EPDM diaphragm (DIN 4807), ensuring the unit stays flexible and reliable despite the intense thermal loads of solar loops.
The SP-24 comes equipped with a 1" 304 stainless steel connector, offering a lead-free and chemically secure interface. This CE and ISO9001 certified vessel is the professional choice for ensuring the safety and long-term performance of high-capacity residential or commercial solar thermal installations.
Certification
Specifications and Technical Data
| Parameter | Value |
| Model Number | SP-24 |
| Total Tank Volume | 24 liters / 6 gallons |
| Diameter | 29 cm / 11.4 inch |
| Height | 40.7 cm / 16 inch |
| Net Weight (NW) | 3.6 kg / 7.9 lbs. |
| Gross Weight (GW) | 4.5 kg / 9.9 lbs. |
| Shipping Volume | 1.42 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-24 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: The SP-24, like the rest of the Solar-Plus series, is built with a tough cold-rolled carbon steel shell designed to handle a maximum working pressure of 150 PSI (10 Bar).
A: The SP-24 provides 24 liters (6.0 gallons) of expansion volume and is specifically sized to support a 100-gallon water heater. It is engineered for solar hot water systems and evacuated tubes, safely handling thermal liquid expansion at extreme temperatures up to 130°C (266°F).
A : Yes. Stagnation occurs when the solar pump stops but the sun continues to heat the collectors. The SP-24 is specifically built with a high-temperature EPDM diaphragm and a heat-resistant liner to safely absorb the massive volume of expanded fluid during these periods without compromising the tank's integrity.
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