Rheem 13kW Compact Electric Tankless Water Heater vs Rheem 2.5 Gallon Mini-Tank Electric: Spec Comparison
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When you compare the rheem 13kw compact electric tankless water heater vs 2 5 gallon mini, you see two distinct approaches to hot water. Both units are electric and designed for residential use. The main difference lies in capacity and form. The tankless model provides continuous hot water on demand. The mini-tank stores a small reserve for immediate access. You must decide which delivery method fits your space and usage needs.
Key differences
| Aspect | Rheem 13kW Compact Electric Tankless Water Heater | Rheem 2.5 Gallon Mini-Tank Electric Water Heater |
|---|---|---|
| Capacity | Tankless (up to 3.17 GPM flow) | 2.5 gallons |
| Dimensions | 12.6" L x 8.25" W x 3.63" H | 11" L x 11" W x 17" H |
| Weight | 3.97 pounds | 17.6 pounds |
| Temperature Control | Digital, +/-1 degree accuracy | Adjustable 50°F-140°F |
| Installation | Side water connections, wall mount | Floor or wall mountable |
Which one should you choose?
Choose Rheem 13kW Compact Electric Tankless Water Heater if
- You need hot water for multiple fixtures without running out.
- You have limited vertical space but can accommodate a wider unit.
- You prefer precise digital temperature adjustments.
Choose Rheem 2.5 Gallon Mini-Tank Electric Water Heater if
- You need immediate hot water at a single point of use.
- You want a unit that can sit on the floor.
- You prefer a simple analog temperature adjustment.
Verdict: The tankless heater suits those who need continuous hot water for sinks or showers in tight spaces. The mini-tank is better for small bathrooms or kitchens where immediate access to a fixed volume is key. Choose based on whether you prioritize unlimited flow or instant stored reserves.
Specs: Tankless vs Mini-Tank
Physical footprint
The Rheem 13kW Compact Electric Tankless Water Heater measures 12.6 inches long, 8.25 inches wide, and 3.63 inches high. It weighs just 3.97 pounds. This small size allows it to fit in tight spaces. The Rheem 2.5 Gallon Mini-Tank Electric Water Heater is larger. It stands 17 inches tall with an 11-inch width and length. It weighs 17.6 pounds. The tankless unit saves significant space. You can mount it on a wall or place it in a small closet. The mini-tank requires more room due to its vertical design. If space is limited, the tankless model is the better choice.
Hot water capacity
Capacity defines how much hot water each unit holds or provides. The Rheem 2.5 Gallon Mini-Tank Electric Water Heater holds 2.5 gallons of pre-heated water. It is ideal for point-of-use applications where you need immediate hot water. The Rheem 13kW Compact Electric Tankless Water Heater does not store water. It heats water on demand. Its flow rate is up to 3.17 GPM. This means it provides a continuous supply as long as the heater runs. If you need a steady stream for a shower, the tankless model wins. If you need a small reserve for a sink, the mini-tank is sufficient.
Voltage requirements
Both units operate on electric power, but the Rheem 13kW Compact Electric Tankless Water Heater requires a 240V connection. This is standard for many electric tankless heaters. The Rheem 2.5 Gallon Mini-Tank Electric Water Heater is also electric. The data does not specify its exact voltage, but small mini-tanks often use standard 120V outlets. You must check your home’s electrical setup. A 240V circuit may require a dedicated breaker and thicker wiring. If you have a standard 120V outlet, the mini-tank might be easier to install. If you already have 240V available, the tankless unit is ready to go.
Temperature control
Precise temperature control is vital for comfort and safety. The Rheem 13kW Compact Electric Tankless Water Heater features an external adjustable digital thermostatic control. It has an LED display and allows adjustments in 1-degree Fahrenheit increments. This offers high precision. The Rheem 2.5 Gallon Mini-Tank Electric Water Heater has an adjustable temperature control ranging from 50°F to 140°F. It lacks the digital display and fine-tuning of the tankless model. The tankless unit gives you exact control over the output temperature. The mini-tank provides a broader range but with less precision.
Build quality
Durability depends on the internal components. The Rheem 13kW Compact Electric Tankless Water Heater uses durable copper immersion two heating elements. These elements are field serviceable, which can extend the unit's life. It also boasts 99.8% energy efficiency. The Rheem 2.5 Gallon Mini-Tank Electric Water Heater features an enameled glass-lined tank. This lining is designed to protect against corrosion and extend the tank's life. The tankless model uses simple copper elements. The mini-tank relies on a protected reservoir. Both designs aim for longevity, but the tankless unit has fewer parts that can fail over time.
Which Rheem water heater fits you
Small household needing endless hot water
This unit delivers up to 3.17 GPM for continuous hot water. Its 13kW power handles multiple uses without running out. The compact size fits tight spaces. You get precise temperature control with LED display. This is ideal for showers and sinks where flow matters most.
Kitchen or bathroom point-of-use storage
This model stores 2.5 gallons of pre-heated water. It provides immediate hot water for small sinks. The enameled glass tank ensures durability. You can mount it on the wall or floor. This is perfect for locations where you need a ready reserve of hot water.
DIY installer wanting simple setup
The tankless heater includes 1/2 NPT adapters and compression connections. It features self-modulating power for easy integration. The compact dimensions simplify placement. You avoid the complexity of tank maintenance. This design focuses on straightforward installation and minimal upkeep for residential systems.
The products compared
Rheem 13kW Compact Electric Tankless Water Heater
Best for: space-constrained installations with 240V power
- Voltage
- 240V
- Dimensions
- 12.6 × 8.25 × 3.63 inches
- Weight
- 3.97 pounds
View on Amazon: Rheem 13kW Compact Electric Tankless Water Heater Affiliate link
The Rheem RTEX-13 is a compact electric tankless water heater designed for point-of-use or whole-home applications. It delivers up to 3.17 gallons per minute with a 13kW heating capacity. The unit features a 240V power requirement and weighs just 3.97 pounds. Its digital thermostat offers precise temperature adjustments. This model suits those needing continuous hot water without the bulk of a storage tank.
Pros
- High energy efficiency rated at 99.8%
- Precise digital control with +/-1 degree accuracy
- Compact dimensions of 12.6 x 8.25 x 3.63 inches
- Includes 1/2 NPT adapters and water-saver shower head
Cons
- Requires a dedicated 54-amp circuit
- Limited to 240V power supply
- Flow rate capped at 3.17 GPM
Good fit if
- You need a space-saving solution for small bathrooms
- You want precise temperature control for comfort
- You have the electrical capacity for a 54-amp circuit
Skip if
- You lack the wiring for a 240V, 54-amp setup
- You require higher flow rates for multiple simultaneous fixtures
- You prefer a storage tank for backup water supply
Verdict: Rheem RTEX-13 13kW Electric Tankless offers efficient, compact heating for users with adequate electrical infrastructure. It fits best in homes where space is limited and precise temperature control is a priority.
Rheem 2.5 Gallon Mini-Tank Electric Water Heater
Best for: Single sink point-of-use hot water
- Fuel Type
- Electric
- Capacity
- 2.5 gallons
- Temperature Control
- 50°F-140°F
- Dimensions
- 11"W x 17"H x 11"L
- Weight
- 17.6 pounds
View on Amazon: Rheem 2.5 Gallon Mini-Tank Electric Water Heater Affiliate link
This Rheem unit provides 2.5 gallons of hot water for point-of-use applications. It measures 11 by 17 by 11 inches and weighs 17.6 pounds. You can adjust the temperature from 50 to 140 degrees Fahrenheit. The enameled glass-lined tank helps extend the unit's life. It mounts on the floor or wall using the included bracket. This compact design fits tight spaces under sinks or in small cabinets.
Pros
- 2.5-gallon capacity for immediate hot water access
- Adjustable thermostat range from 50 to 140 degrees Fahrenheit
- Compact 11 by 17 by 11 inch footprint
- Wall or floor mounting options included
Cons
- Limited 2.5-gallon storage capacity
- Requires frequent reheat for high demand
- No digital display for temperature monitoring
Good fit if
- You need hot water for a single sink
- You have limited space under a counter
- You want a simple point-of-use heater
Skip if
- You need to supply multiple fixtures simultaneously
- You require continuous hot water flow
- You need a high-capacity tank for showers
Verdict: Rheem 2.5 Gal Mini-Tank Electric Water Heater suits you if you need a small, dedicated hot water source for one sink. It does not work for whole-house needs or high-flow showers.
Specifications side by side
| Spec | Rheem 13kW Compact Electric Tankless Water Heater | Rheem 2.5 Gallon Mini-Tank Electric Water Heater |
|---|---|---|
| Fuel Type | not stated | Electric |
| Capacity | not stated | 2.5 gallons |
| Temperature Control | not stated | 50°F-140°F |
| Dimensions | not stated | 11"W x 17"H x 11"L |
| Voltage | 240V | not stated |
| Weight | 3.97 pounds | 17.6 pounds |
| Size | Compact | 2.5 Gallon |
| Color | Gray | Gray |
| Model | RTEX-13 | PROE2 1 RH MT |
Frequently asked questions
Can the Rheem 13kW tankless unit replace a traditional tank?
Yes, it provides continuous hot water for whole-house use. It delivers up to 3.17 GPM when inlet water is around 67°F. This flow rate supports showers and multiple sinks. However, it requires a 240V electrical circuit. You must ensure your home has adequate power infrastructure before installing this unit.
Is the 2.5 gallon mini-tank suitable for a shower?
No, it is not designed for shower use. This unit is intended for single sink point-of-use applications only. It lacks the capacity and flow rate needed for bathing. If you need hot water for a shower, you should choose the 13kW tankless model instead. The mini-tank is best for handwashing or laundry sinks.
How much space does each unit require?
The 13kW tankless model measures 12.6 inches long, 8.25 inches wide, and 3.63 inches high. It weighs 3.97 pounds. The 2.5 gallon mini-tank is larger, measuring 11 inches wide, 17 inches high, and 11 inches long. It weighs 17.6 pounds. Choose the tankless unit for tighter spaces.
Does the tankless heater need a gas line?
No, it runs entirely on electricity. The Rheem 13kW model requires a 240V power connection. It does not use gas or propane. You must have a dedicated 240V circuit installed by a qualified electrician. This electrical requirement is essential for safe and proper operation of the unit in your home.
What is the difference in capacity between these two heaters?
The tankless unit provides endless hot water on demand. It does not store water, so you never run out. The mini-tank holds 2.5 gallons of heated water. Once that hot water is used, it must reheat. The tankless option is better for high-demand areas, while the mini-tank suits low-demand spots.
Can I install the 2.5 gallon tank under a counter?
Yes, its compact dimensions allow for under-counter installation. It measures 11 by 11 by 17 inches. This size fits well in cabinets or utility closets. It is designed for point-of-use locations like a bathroom or kitchen sink. Ensure the area has proper ventilation and access to a standard electrical outlet.
Which model is lighter to handle during installation?
The Rheem 13kW tankless heater is significantly lighter. It weighs only 3.97 pounds. The 2.5 gallon mini-tank weighs 17.6 pounds. The lighter tankless unit is easier to mount on a wall. The heavier mini-tank requires a sturdy surface to support its weight when filled with water.