Ecosmart US EcoSmart ECOS 27 Tankless or Ecosmart US Performance 18kW SM 3.5GPM Electric Tankless Water Heater? Which Ecosmart US Model to Buy
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This comparison covers the ecosmart us ecosmart ecos 27 tankless vs performance 18kw sm 3 5gpm. Both are electric tankless water heaters from Ecosmart US designed for on-demand heating. They share the same fuel type and self-modulating technology for consistent temperature control. The main difference lies in their power output and flow capacity. The ECOS 27 offers higher wattage for greater flow, while the Performance 18kW provides a lower capacity option. You need to match the unit to your specific household water usage needs.
Key differences
| Aspect | EcoSmart 27 kW Electric Tankless Water Heater | Ecosmart US 18kW Electric Tankless |
|---|---|---|
| Wattage | 27 kW | 18 kW |
| Flow Rate | 2.7 to 6.6 GPM | 3.5 GPM |
| Dimensions | 19 x 4.25 x 9.25 inches | 20 x 7 x 7 inches |
| Weight | 10.9 pounds | 11 pounds |
| Color | White | Gray |
Which one should you choose?
Choose EcoSmart 27 kW Electric Tankless Water Heater if
- You need higher flow rates for multiple fixtures or higher inlet temperatures.
- You prefer a slimmer profile for installation in tight spaces.
- You want a new unit with a five-year leak warranty.
Choose Ecosmart US 18kW Electric Tankless if
- You require a lower wattage unit for a single bathroom or point-of-use application.
- You are open to a refurbished model that is tested and certified.
- You prefer a square-shaped unit design.
Verdict: Choose the ECOS 27 if you need maximum flow capacity and a newer warranty structure. Select the Performance 18kW if you have lower hot water demands or prefer a refurbished unit. Both models deliver efficient electric heating without the need for venting.
Ecosmart ECOS 27 vs Performance 18kW
Wattage and power
The EcoSmart ECOS 27 delivers 27 kW of power, while the Performance 18kW SM model provides 18 kW. Higher wattage generally supports higher flow rates or better performance in colder inlet water. The ECOS 27 has a 50% power advantage. This means it can heat water more aggressively or maintain temperature in colder climates more effectively than the lower-wattage unit. You need to check your electrical panel capacity, as the 27 kW model requires significantly more amperage. The 18 kW unit is easier on your home’s electrical infrastructure. If you have ample electrical service, the higher power offers more flexibility.
Flow rate capacity
Flow rate determines how much hot water you get simultaneously. The Performance 18kW SM lists a flow rate of 3.5 GPM in its key specs, though attributes mention 5.0 GPM. The ECOS 27 provides between 2.7 and 6.6 GPM depending on inlet water temperature. The ECOS 27 has a wider range and a higher potential maximum flow rate. This makes it better for supplying multiple fixtures or handling larger showers. The Performance 18kW is suitable for point-of-use or single-fixture applications. You should choose the ECOS 27 if you need higher volume hot water. The lower wattage unit may struggle to maintain temperature at higher flow rates.
Physical dimensions
Size matters for installation space. The ECOS 27 measures 19 x 4.25 x 9.25 inches. The Performance 18kW SM measures 20 x 7 x 7 inches. The ECOS 27 is narrower and slightly shorter. It is also lighter at 10.9 pounds compared to 11 pounds for the Performance model. The Performance unit is wider, which might be an issue in tight spaces. The ECOS 27 has a more compact footprint for wall mounting. You can install either on a wall or at point of use. Both are 90% smaller than traditional tank heaters. The ECOS 27 is the more space-efficient choice for narrow cabinets.
Temperature control
Both units use self-modulating technology to adjust heating based on flow. The ECOS 27 specifies temperature control within 1 degree of the selected setting. This ensures consistent performance and efficiency. The Performance 18kW SM data does not specify the exact temperature variance. Both provide endless on-demand hot water. You get consistent hot water when you need it with either model. The ECOS 27 explicitly states its precision. This is useful if you are sensitive to temperature fluctuations. The Performance unit is refurbished and tested to work like new. You should verify the control precision if this is a critical factor for you.
Condition and warranty
The condition of the unit affects your decision. The Performance 18kW SM is listed as a refurbished product. It is tested, cleaned, and repackaged. It may arrive in a generic box. The ECOS 27 is presented as a new product. Warranty details are provided for the ECOS 27: five years limited on leaks and one year parts. The Performance unit data does not list warranty terms. You might prefer a new unit with clear warranty coverage. The refurbished option could be less expensive, but you must check the warranty status. New units typically offer more predictable support and condition.
Choose the Right EcoSmart Model
High-flow bathroom needs
The ECOS 27 delivers up to 6.6 GPM, depending on inlet water temperature. Its 27 kW power handles higher demand better than the 18 kW model. You get consistent temperature control within one degree. This unit is ideal for primary bathrooms where flow rate matters most for your comfort.
Point-of-use sink
The Performance 18kW model offers 3.5 GPM, which is sufficient for a single sink or small application. Its compact 7-inch width fits tight spaces easily. You save energy by heating only when needed. This lower wattage is perfect for offices, breakrooms, or remote sinks with low usage.
Compact installation space
This model measures 7 inches wide and 7 inches deep. It is significantly narrower than the ECOS 27, which is 9.25 inches wide. You can mount it in tighter corners or closets. The 18 kW power is adequate for modest hot water needs without requiring a large footprint.
The products compared
EcoSmart 27 kW Electric Tankless Water Heater
Best for: Single bathroom or point-of-use hot water
- Fuel Type
- Electric
- Flow Rate
- 2.7 to 6.6 GPM
- Wattage
- 27 kW
- Voltage
- 240 V
- Temperature Control
- within 1 degree
- Dimensions
- 19 x 4.25 x 9.25 inches
View on Amazon: EcoSmart 27 kW Electric Tankless Water Heater Affiliate link
The EcoSmart ECOS 27 is a 27 kW electric tankless water heater designed for point-of-use or low-flow applications. It delivers between 2.7 and 6.6 gallons per minute depending on inlet water temperature. The unit maintains temperature within 1 degree and is 90% smaller than traditional tanks. It measures 19 x 4.25 x 9.25 inches and weighs 10.9 pounds. This model suits bathrooms, small sinks, or office breakrooms.
Pros
- 27 kW power output for consistent hot water
- Temperature control within 1 degree of selected setting
- Compact dimensions of 19 x 4.25 x 9.25 inches
- 96% thermal energy efficiency
Cons
- Flow rate maxes at 6.6 GPM, limiting whole-house use
- Only 1 year parts warranty compared to 5 years on leaks
- Requires 240V and 112.5 Amps for operation
Good fit if
- You need hot water for a single bathroom or small sink
- You have the electrical capacity for a 240V, 112.5 Amp circuit
- You want a compact unit for point-of-use installation
Skip if
- You need to supply hot water for multiple simultaneous showers
- Your electrical panel cannot support 112.5 Amps at 240V
- You require a longer than 1 year parts warranty
Verdict: EcoSmart ECOS 27 Electric Heater is a compact, efficient choice for single-point applications like bathrooms or small sinks where high flow is not required. It fits buyers with adequate electrical capacity who prioritize space savings and precise temperature control.
Ecosmart US 18kW Electric Tankless
Best for: single sink point-of-use installations
- Fuel Type
- Electric
- Flow Rate
- 3.5 GPM
- Wattage
- 18 kW
- Dimensions
- 20 x 7 x 7 inches
- Weight
- 11 pounds
View on Amazon: Ecosmart US 18kW Electric Tankless Affiliate link
This is a refurbished 18 kW electric tankless water heater. It delivers 3.5 GPM at 240 volts. The unit measures 20 x 7 x 7 inches and weighs 11 pounds. It is designed for point-of-use or small household applications. You get a certified refurbished unit that looks and works like new. It ships with all accessories in a generic box.
Pros
- 18 kW heating element
- Compact 7-inch width
- Refurbished and certified
- Electric fuel type
Cons
- 3.5 GPM flow rate is lower than the 27 kW model
- Refurbished condition with generic packaging
- No remote or app control listed
Good fit if
- You need a compact unit for a single sink
- You want a certified refurbished electric heater
- You have 240-volt electrical capacity
Skip if
- You need high flow for multiple showers
- You require a brand new unit with original packaging
- You want smart home integration
Verdict: Ecosmart US Performance 18kW Electric is a compact, certified refurbished option for low-flow needs. It suits single-sink installations where space is tight and high capacity is not required.
Specifications side by side
| Spec | EcoSmart 27 kW Electric Tankless Water Heater | Ecosmart US 18kW Electric Tankless |
|---|---|---|
| Fuel Type | Electric | Electric |
| Flow Rate | 2.7 to 6.6 GPM | 3.5 GPM |
| Wattage | 27 kW | 18 kW |
| Voltage | 240 V | not stated |
| Temperature Control | within 1 degree | not stated |
| Dimensions | 19 x 4.25 x 9.25 inches | 20 x 7 x 7 inches |
| Weight | 10.9 pounds | 11 pounds |
| Color | White | Gray |
| Model | ECOS 27 | Performance 18KW SM 3.5GPM Electric |
Frequently asked questions
Which EcoSmart model is best for a single bathroom?
The ECOS 27 is the better choice for a single bathroom. It delivers higher flow rates compared to the 18kW model. Its 27 kW power handles the demand of a shower and sink simultaneously. You get precise temperature control within one degree. This makes it reliable for daily use in a bathroom setting.
Can the 18kW model handle multiple fixtures at once?
No, the 18kW Performance model is designed for point-of-use installations. It is best suited for a single sink where high flow is not required. It does not have the wattage to support multiple fixtures running together. If you need hot water for more than one tap, you should choose the higher capacity ECOS 27.
What are the physical dimensions of the ECOS 27?
The ECOS 27 measures 9.25 inches in width and length, with a height of 19 inches. It weighs 10.9 pounds. These compact dimensions allow it to fit in tight spaces. The white color helps it blend into most utility areas or closets without drawing attention.
How large is the Performance 18kW unit?
The Performance 18kW unit is very compact, measuring 7 inches in width and length. Its height is 20 inches. It weighs 11 pounds. This small footprint makes it ideal for under-sink installations. The gray finish is discreet and functional for low-flow applications.
Do these heaters require a 240V electrical connection?
Yes, both the ECOS 27 and the Performance 18kW require a 240V electrical supply. They are electric tankless heaters that rely on this voltage to generate heat. You must ensure your home has the correct electrical capacity before installation. This is a standard requirement for this type of on-demand heating equipment.
Is the ECOS 27 suitable for point-of-use applications?
Yes, the ECOS 27 is suitable for point-of-use applications. It is a compact choice for single-point locations like small sinks or bathrooms. While it has higher power, it still fits in tight spaces. You get precise temperature control and space savings, making it versatile for various small installations.
What is the difference in wattage between the two models?
The ECOS 27 has 27 kW of wattage, while the Performance 18kW has 18 kW. This 9 kW difference allows the ECOS 27 to support higher flow rates. Higher wattage generally means better performance in colder inlet water. You should choose the higher wattage model if you need more hot water volume.