OIUNUNO Expansion Tank Steel Mnpt Rv Marine 746253299340 2.1 3/4

( Brand: Oiununo ), ( Part Type: Expansion Rv Tank ), ( Model Name: Oiununo-tank-1 ), ( Size: 2.1 Gallons ), ( Color: Off-white ), ( Capacity: 2.1 ), ( Material: Carbon Steel, 304 Stainless Steel ), ( Polypropylene: Pp, Epdm ), ( Unit Count: 1.0 ), ( UPC: 746253299340 ), ( Package Dimensions Lxwxh: 13.11x8.58x8.5 Inches ), ( Weight: 5.83 Pounds )

Review OIUNUNO Potable Expansion Tank 2.1 Gal Stainless Steel 3/4 Inch Mnpt Rv Marine

OIUNUNO 2.1 Gal Expansion Tank for RV, Marine Applications - Steel MNPT Design

The OIUNUNO 746253299340 Expansion Tank is an essential component for recreational vehicles (RVs) and marine applications. Designed with a 2.1-gallon capacity, this expansion tank is engineered to accommodate the necessary coolant expansion during engine operation.

Constructed from high-quality steel, this expansion tank boasts impressive durability and resistance to corrosion. Its MNPT (Male National Pipe Thread) design ensures a secure connection to your cooling system, allowing for reliable performance even in the most challenging environments.

Measuring approximately 10.2 inches in length, 6.5 inches in width, and 9.2 inches in height, the compact size of this expansion tank makes it an ideal fit for limited spaces in RVs and marine applications. The tank features a convenient sight glass, allowing you to easily monitor coolant levels without the need for removal.

Installing this expansion tank is a straightforward process. It comes equipped with a filler neck and drain plug for easy access during maintenance. Additionally, its threaded connections allow for simple integration into your existing cooling system.

The OIUNUNO 746253299340 Expansion Tank is specifically designed to meet the demanding requirements of RV and marine applications. Its robust construction, secure connections, and easy maintenance make it an indispensable addition to your vehicle or watercraft's cooling system. By ensuring proper coolant expansion and maintaining optimal system performance, this expansion tank helps protect your engine from damage and extends its lifespan.

The O'Reilly Automotive 2.1 gallon steel expansion tank (part number 746253299340) is a component used in RV, marine, and other applications to accommodate the increase in coolant volume due to the engine's thermal expansion. Let's discuss some potential advantages and disadvantages of purchasing this product.

1. Capacity: With a 2.1 gallon (7.95 liter) capacity, this expansion tank can effectively accommodate the coolant expansion in larger systems.

2. Material: The steel construction ensures durability and resistance to corrosion, which is crucial for long-term use in harsh marine or RV environments.

3. MNPT Threading: This tank features MNPT (Marine National Park Transportation) threading, making it a versatile choice for RV and marine applications.

4. Leak-free Design: The O-ring seal helps prevent leaks, ensuring that the coolant remains contained within the system.

5. Universal Fitment: This tank is designed to fit a wide range of applications and can be used as a replacement for many different makes and models.

1. Weight: Steel components are generally heavier than their plastic counterparts, which could make installation and transportation more laborious.

2. Potential for Condensation: In cold environments, the tank might accumulate condensation, which could dilute the coolant and affect its performance.

3. Limited Warranty: O'Reilly Automotive offers a limited warranty on this product, but the specifics and length of the warranty are not explicitly stated in the product description.

In conclusion, the O'Reilly Automotive 2.1 gallon steel expansion tank (746253299340) presents a robust and durable solution for accommodating coolant expansion in RV and marine applications. Its advantages include a large capacity, corrosion-resistant steel construction, MNPT threading, and leak-free design. However, it is heavier than plastic alternatives, and potential issues with condensation and a limited warranty might be concerns for some buyers.

If you're looking for a high-capacity, durable, and leak-free expansion tank for your RV or marine application, this product from O'Reilly Automotive is a solid choice. Keep in mind the potential weight concerns and consider the warranty information before making your purchase.

Details:

This expansion tank is certified for potable water applications. Please understand that some factors like weather, high postal traffic, and the performance of shipping companies are outside our control. Pump start/stop cycles. This function supports the reduction of relief valve discharge and helps mitigate water hammer effects in piping systems.

Handles water hammer impact and cyclic pressure fluctuations Features: Dual O-Ring Leak Resistant Air Valve: Our expansion tank features a leak-resistant air valve with double O-ring seals, designed to help reduce pressure loss and leakage in thermal systems. Thick-walled Handles High Pressure: This water expansion tanks feature thick-walled carbon steel construction with factory test pressure rating of 207 PSI. By doing so, it contributes to the protection of your plumbing and water heater.

Enjoy Consistent System Performance: Our expansion tank is designed to manage pressure increases caused by thermal expansion, helping maintain below the water heater relief valve setting. For Various Water System Applications: This expansion tank ideal for modern, high efficiency systems including well water systems, hot solar thermal marine, RV and other applications. While factory-tested to 207 PSI, our expansion tanks require operating pressures 150 PSI for sustained safety and service life. Potable Thermal Expansion Tank 2.1 Gallon, 3/4 MNPT Connection, Compact Design for Water Heater, RV, Marine, Boat, Off-Grid Systems, Residential Plumbing Solar Thermal:: Oiununo thermal expansion tank is suitable various water system applications, including residential well supply systems, heating boiler solar marine, RV systems and other applications.

specifications wateheat:

• brand: Oiununo
• part type: Expansion Rv Tank
• model name: Oiununo-tank-1
• size: 2.1 Gallons
• color: Off-white
• capacity: 2.1
• material: Carbon Steel, 304 Stainless Steel
• polypropylene: Pp, Epdm
• unit count: 1.0
• upc: 746253299340
• package dimensions lxwxh: 13.11x8.58x8.5 Inches
• weight: 5.83 Pounds

seller wateheat:

• # reviews: 646
• city: San Francisco, California
• rating: 100.0%

payments wateheat:

• other
• wallet: Apple-pay
• credit card: Visa

returns wateheat:

• policy: Returns Accepted
• paid by: Seller
• time: 30 Days
• method: Money back

general wateheat:

• Heating, Cooling Air > Water Heaters > Water Heater Parts
• condition: New

offer wateheat:

• quantity: 1
• sold: 0
• options: Ship-to-home
• availability: In Stock
• started: June 7, 2026

shipping wateheat:

• class: Standard
• transit: 3-5 Days
• service: Standard
• cost: $0.00
• type: Fixed

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