EcoSmart ECO 8 vs Rheem RTEX-06T

Last updated: October 31, 2026

The EcoSmart ECO 8 is the better tankless water heater overall, rated 3.2 to 2.4. The EcoSmart ECO 8 leads on warranty and efficiency. The Rheem RTEX-06T costs $30 less ($189 vs $219).

EcoSmart ECO 8 vs Rheem RTEX-06T

Prices were last checked October 31, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.

Which should you buy?

Scores side by side

Each factor is scored 0-100 against the same fixed reference points for every electric tankless water heater; a clear win is highlighted. How we rank explains each one.

Factor weightEcoSmart ECO 8Rheem RTEX-06T
Overall rating3.2/52.4/5
Value 35%38 $27.38 per kW ($219, 8 kW)33 $29.08 per kW ($189, 6.5 kW)
Heating power 25%0 8 kW0 6.5 kW
Efficiency 15%75 0.96 UEF50 0.94 UEF
Warranty 25%100 limited lifetime heat exchanger warranty29 5-year heat exchanger warranty

Specifications

EcoSmart ECO 8Rheem RTEX-06T
Heating
FuelElectricElectric
Electric power8 kW6.5 kW
Max flow2 GPM1.6 GPM
UEF0.960.94
Installation
Voltage240 V240 V
Breakers40 A total30 A total
Weight4.8 lb4 lb
Features
Built-in recirculationNoNo
Wi-FiNoNo
Heat exchanger warrantyLimited lifetime5 years
Parts warranty-1 year

All tankless water heater comparisons →