TP-18 is designed specifically to absorb expanded water in closed, hot water systems, protecting water heating systems from excessive pressure and potentially hazardous conditions.
TP-18 has a total volume of 18 liters (4.5 gallons). The tank is designed to safely maintain water pressure levels with a maximum operating pressure of 10 bar (150 psi) and a maximum operating temperature of 90 °C (194 °F).
It is factory pre-charged with nitrogen to 3.5 bar (50 psi) for highly stable and safe system performance. With a diameter of 28.0 cm (11.0 inches) and a height of 37.9 cm (14.9 inches), this mid-sized tank provides increased shock absorption and expansion capacity while remaining highly adaptable for residential water heaters and plumbing systems.
Product Overview
The TP-18 is an 18-liter (4.5-gallon) thermal expansion tank engineered specifically for residential closed-loop hot water systems. It serves as a high-capacity safety buffer, absorbing thermal expansion to stabilize system pressure and protect your water heater from excessive stress and relief valve discharges.
Key technical advantages include an FDA-grade polypropylene liner and a heavy-duty butyl diaphragm with an exceptional 400% elongation property. This internal architecture ensures water never contacts the carbon steel shell, maintaining a contaminant-free environment and superior resilience during constant expansion cycles.
Built for superior reliability, the TP-18 features a stainless steel connection with patented Leak Safe technology and a Triple Grade Almond (RAL 1015) epoxy finish. This unit delivers a maintenance-free performance that ensures the longevity of your system and your absolute peace of mind.
Certification
Specifications and Technical Data
| Parameter | Value |
| Model Number | TP-18 |
| Total Tank Volume | 18 liters / 4.5 gallons |
| Diameter | 28.0 cm / 11.0 inch |
| Height | 37.9 cm / 14.9 inch |
| Net Weight (NW) | 3.4 kg / 7.5 lbs. |
| Gross Weight (GW) | 3.8 kg / 8.4 lbs. |
| Shipping Volume | 1.08 CUF |
| Operating Temperature | 1 - 90°C / 34 - 194°F |
| Factory Pre-charge | 3.5 bar | 50 psi |
| Max. Operating Pressure | 10 bar | 150 psi |
| Connection | 3/4” NPT Stainless Steel |
| Liner Material | Polypropylene (FDA grade) |
| Diaphragm Material | Heavy-Duty Butyl Rubber |
| Shell | Cold Rolled Carbon Steel |
| External Coating | Triple Grade Almond (RAL1015) Paint |
| Pre-charge Gas | 100% Nitrogen |
Key Features & Design Advantages
How the THERMAL-PLUS Pressure Tank Works
In closed hot water systems, thermal expansion occurs naturally as domestic water is heated. The TP-18 works in conjunction with a backflow preventer or check valve to safely absorb this expanded water. It stores the expanded water securely between the heavy-duty butyl rubber diaphragm and the polypropylene liner, while the nitrogen-filled air chamber compresses to accommodate the volume change. By controlling this excessive pressure, it safely maintains water pressure levels and avoids relief valve discharge.
Key benefits
Typical Applications
Frequently Asked Question (FAQ)
The TP-18 utilizes a heavy-duty butyl rubber diaphragm engineered with a massive 400% elongation physical property, allowing it to safely stretch and absorb expanded water volume without tearing.
Yes, the cold-rolled carbon steel shell is coated in a highly durable Triple Grade Almond (RAL 1015) paint, which provides excellent rust resistance while blending cleanly with most standard home utility systems.
It is very lightweight, with an empty net weight of just 7.5 lbs (3.4 kg)
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.
Watch our video to explore the possibilities and see how we help your products stand out in the market.
Downloads & Certification Links
Detailed product information and data
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