Tankless Water Heater Electric 13.8kW 240V - Compact Endless Hot Water

In this review the WINTEMP tankless electric water heater is assessed as a compact, high-output unit best suited for single showers or small households. The most compelling reason to consider it is the combination of a true on-demand supply and self-regulating power that aims to reduce electricity use while delivering stable hot water; the digital display and ETL certification add confidence for a permanent installation. Buyers must verify electrical requirements before purchase to ensure compatibility with their panel and wiring.

Key Features

• 13.8 kW 240V rating: Provides fast heating that can deliver up to 3.1 gallons per minute, enough for one to two usage points like a bathroom shower.
• Self-regulating temperature control: Automatically adjusts power based on incoming water temperature and flow to keep output steady and maximize efficiency.
• Digital LED display: Shows set temperature from 86F to 140F so users can quickly confirm and adjust output at a glance.
• Space saving wall-mount design: Small footprint at 9.7in x 14in x 3.4in, occupying roughly 90% less space than a typical storage tank heater.
• Safety protections and certification: Includes leakage, overheat, and dry-fire protection and is ETL certified for safer everyday use.
• Energy saving operation: When water is not flowing the unit uses no energy and the self-regulating system can reduce electricity use compared with tank heaters.

Who It's For

The WINTEMP WN13 is ideal for homeowners needing a compact solution for a bathroom shower, small apartment, garage sink, or shop where a dedicated 240V supply can be installed. It suits people who want instant hot water and lower standby energy loss compared with tank systems.

It is not for larger families or whole-home replacement unless multiple units or a higher-capacity model are used, and installers should be cautious if their panel cannot support a 60 Amp double-pole breaker and 6 AWG wiring as required.

Pros & Cons

Pros

• Compact wall-mounted size saves space and fits tight installations.
• Self-regulating technology and digital display provide consistent temperatures and clear control.
• ETL certified with multiple safety protections for peace of mind.
• Energy efficient with near-zero standby consumption when idle.

Cons

• Requires a substantial electrical circuit (1 x 60 Amp DP breaker and 6# AWG wiring), which may need panel upgrades.
• Maximum flow around 3.1 gpm limits simultaneous use to one or two fixtures.

Specifications

Model Rating	13.8 kW (240V)
Maximum Amperage	58 A
Recommended Breaker	1 x 60 Amp double-pole
Required Wiring	6# AWG with ground
Dimensions	9.7in x 14in x 3.4in
Water Connection	1/2 in NPT
Max Flow	3.1 gallons per minute

Our Verdict

The WINTEMP 13.8 kW tankless electric heater is a strong value for a single shower or small point-of-use application where wall space is limited and a 240V circuit is available. Its self-regulating control, digital temperature readout, and ETL safety features make it a practical energy-saving alternative to a storage tank, though buyers should confirm electrical capacity and expect modest flow limits for simultaneous fixtures.

Frequently Asked Questions

What electrical supply is required?
The unit requires a 240V supply with a recommended 200A household service, 1 x 60 Amp double-pole breaker and 6# AWG wiring with ground.

How much hot water can it deliver?
Maximum output is about 3.1 gallons per minute, suitable for one to two usage points but likely insufficient for multiple showers at once.

Is it safe to use?
Yes, the heater has leakage, overheat, and dry-fire protections and is ETL certified; follow installation guidelines and local electrical codes.