Which handles more hot water at once?

The Titan N270, at 5 GPM versus 4.5 GPM for the Opti 27. Both are 27kW, so the gap is small and either suits two baths in a cold climate.

Is the Opti 27 worth the extra $234?

If warranty and control matter, yes. The Opti 27 carries a 25-year residential warranty and Wi-Fi app control; the Titan's listing states no warranty length.

On paper the Opti 27, because its 25-year residential warranty is the longest in this pair. The Titan's listing gives no warranty term, so there is nothing to compare against.

What electrical work does each need?

The Titan needs two 60A breakers and 6 AWG wire. The Opti 27 needs three 40A double-pole breakers and 8 AWG wire. Both draw up to 112 amps at 240V, so plan for a large service panel.

Can either replace a tank heater for a whole home?

Yes. Both are 27kW whole-house units. The Titan is rated for 2 baths in cold climates; the Opti 27 can also serve as a point-of-use unit or a booster for a hybrid system.

Which is easier to install in a tight space?

The Titan N270. It measures 10.5 x 9 x 4.5 inches and weighs 11.6 lb, against 16.5 x 14.5 x 3.5 inches for the Opti 27.

Titan N270 Tankless Water Heater vs Optimal Opti 27 Tankless Water Heater

Buy the Titan N270 if you want the lowest price and the highest rated flow for a whole-home install. Buy the Opti 27 if you want a long warranty, Wi-Fi control and tighter temperature accuracy and will pay about $234 more. As of November 7, 2026, the Titan is $495.00 at Amazon and the Opti 27 is $729.00 at Home Depot.

Today the Titan N270 Tankless Water Heater costs $234.00 less at its best price.

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