Which is better for a whole home?

Both are 27 kW units sized for a whole home in a warm climate or a smaller home in a cold one. The Opti27 Plus adds 208 V support and app control, which helps in more installations.

Is the Opti27 Plus worth the extra money?

At $740.00 versus $549.00 as of November 7, 2026, you pay about $191 more. That buys a 25-year residential warranty and Wi-Fi control, which is a fair trade if you plan to stay in the home.

The Opti27 Plus carries a 25-year residential warranty against 5 years for the EcoSmart. Warranty length is not the same as service life, but it is the clearest durability signal between the two.

Do both need the same electrical work?

Both are 27 kW at 240 V and need multiple dedicated double-pole breakers and a large service panel. The EcoSmart listing specifies three 40 A breakers and a 200 A panel; confirm your panel capacity before buying either.

Which is better for an RV or mobile home?

The EcoSmart is explicitly listed for RV and mobile home use. The Opti27 Plus is listed for residential and commercial use, so check your installation before choosing it for an RV.

Can I control either from my phone?

Only the Opti27 Plus. It connects over Wi-Fi to the Optimal App for temperature changes, usage tracking and notifications. The EcoSmart is set at the unit's digital display.

EcoSmart ECO 27 Tankless Water Heater vs Opti27 Plus 27kW Electric Tankless Water Heater

Both are 27 kW, 240 V electric tankless units that need heavy dedicated circuits, so the choice comes down to warranty and controls versus price. The EcoSmart ECO 27 is about $191 cheaper: $549.00 at Amazon as of November 7, 2026, against $740.00 at Home Depot for the Opti27 Plus. Buy the EcoSmart if budget and a proven simple design matter most; buy the Opti27 Plus if you want Wi-Fi control and a much longer residential warranty.

Today the EcoSmart ECO 27 Tankless Water Heater costs $191.00 less at its best price.

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