5 Best Tankless Water Heater for Bathtub [In 2025]

As a homeowner, having a reliable and efficient water heater is essential, especially when it comes to bathtub usage. Tankless water heaters have gained popularity due to their instant hot water delivery and energy-saving benefits. In this comprehensive review, we’ll explore some of the best tankless water heater options for your bathtub needs, providing you with the information you need to make an informed purchase.

5 Best Tankless Water Heater for Bathtub Reviews

Tankless Electric Hot Water Heater, 4500W 110V Instant Water Heater On Demand Bath Shower with LED Screen Display

Overview

This tankless electric water heater from Tankless Electric Hot Water Heater promises instant hot water delivery, with a temperature range of 86-131°F and a maximum temperature of 131°F. It features a LED screen display for easy temperature monitoring and comes with various safety features, including automatic power-off and over-temperature protection.

Specs

– Display Screen: LED
– Rated Voltage: AC 110V / 50 HZ
– Rated Power: 4500W
– Rated Current: 40A
– Rated Water Pressure: 0.6Mpa
– Waterproof Level: IPX4
– Temperature Range: 30-55°C/86-131°F (Water Flow Adjustable)
– Maximum Temperature: 55°C/131°F
– Water Heater Lift: Unlimited

Pros

– Instant hot water delivery
– Adjustable temperature range
– LED screen display for easy monitoring
– Automatic power-off and over-temperature protection
– Unlimited water heater lift

Cons

– Higher power consumption compared to some other models
– Might not be suitable for high-volume hot water usage

Immersion Water Heater Electric, 2000W Portable Water Heater with 304 S S Guard & LCD Thermometer

Overview

This portable immersion water heater from Immersion Water Heater Electric is a versatile option for bathtub and bucket heating. It features a 2000W heating element that can quickly heat up to 5 gallons of water, along with a stainless steel protective cover and an LCD thermometer for temperature monitoring.

Specs

– Rated Voltage: 110-125V AC
– Rated Power: 2000W
– Heating Capacity: 5 gallons of water
– Protective Cover: Stainless Steel 304
– Temperature Display: LCD Thermometer

Pros

– Fast heating time
– Stainless steel protective cover for safety
– LCD thermometer for easy temperature monitoring
– Versatile for use in bathtubs, buckets, and more
– Lightweight and portable design

Cons

– Limited to 5-gallon heating capacity
– May not be suitable for larger bathtubs or hot tubs

Water Heater for Bathtub and Bucket, 1800W Fast Heating with Real Time Temperature Display

Overview

This 1800W immersion water heater from Water Heater for Bathtub and Bucket offers advanced safety features and precise temperature control. It features an adjustable thermostat, automatic shutoff, and a real-time temperature display, making it a versatile choice for various heating needs.

Specs

– Rated Power: 1800W
– Temperature Range: Up to 175°F (79°C)
– Temperature Adjustment: Adjustable Thermostat
– Safety Features: Automatic Shutoff, Dry Burn Prevention
– Temperature Display: LED Display
– Heating Element: Stainless Steel
– Power Cord: Reinforced 14-gauge

Pros

– Efficient 1800W heating
– Adjustable thermostat for precise temperature control
– Automatic shutoff and dry burn prevention for safety
– Real-time temperature display for easy monitoring
– Durable stainless steel construction

Cons

– Potential discrepancy between displayed and actual water temperature
– May not be suitable for very large bathtubs or hot tubs

Tankless Water Heater Electric 110V, 5000W Instant Water Heater Under Sink

Overview

The ECOTINYMACH 110V tankless water heater is a powerful 5000W unit that promises instant hot water delivery. It features seamless conversion between Fahrenheit and Celsius, making it easy to use, and is designed to be energy-efficient, reducing your electricity bills.

Specs

– Rated Voltage: 110V
– Rated Power: 5000W
– Temperature Display: Fahrenheit and Celsius Conversion
– Installation: Under Sink

Pros

– Instant hot water delivery
– Fahrenheit and Celsius temperature display
– Energy-efficient design
– User-friendly operation

Cons

– Requires professional installation
– May not be suitable for high-volume hot water usage

Immersion Water Heater for Bathtub, Anti-scalding Portable Water Heater with Stainless Steel Cover

Overview

This immersion water heater from HeavenBird features a 1500W heating element that can quickly heat up to 5 gallons of water. It comes with a stainless steel protective cover and built-in safety features, including temperature control and a fuse to prevent overheating and fire hazards.

Specs

– Rated Power: 1500W
– Heating Capacity: 5 gallons of water
– Safety Features: Temperature Control, Fuse
– Protective Cover: Stainless Steel
– Temperature Display: LCD Thermometer

Pros

– Fast heating time
– Stainless steel protective cover for safety
– Built-in temperature control and fuse for added protection
– LCD thermometer for easy temperature monitoring
– Versatile for use in bathtubs, buckets, and more

Cons

– Limited to 5-gallon heating capacity
– May not be suitable for larger bathtubs or hot tubs

Buying Guide: Choosing the Best Tankless Water Heater for Your Bathtub

When selecting the best tankless water heater for your bathtub, consider the following factors:

Power and Heating Capacity

– Determine the size of your bathtub and the amount of hot water you typically need.
– Look for a tankless water heater with sufficient power (in watts) to heat the water quickly and effectively.
– Consider the heating capacity, which is often measured in gallons per minute (GPM) or the amount of water the heater can heat at a given temperature rise.

Temperature Control and Display

– Opt for a tankless water heater with adjustable temperature settings to ensure a comfortable bathing experience.
– Look for models with clear temperature displays, either digital or analog, to easily monitor and adjust the water temperature.

Safety Features

– Prioritize tankless water heaters with built-in safety features, such as automatic shutoff, dry burn prevention, and overheat protection, to ensure safe operation.
– Consider models with stainless steel or corrosion-resistant materials for added durability and safety.

Ease of Installation and Use

– Evaluate the installation requirements, such as power supply and plumbing connections, to ensure compatibility with your home setup.
– Look for user-friendly features, such as intuitive controls and clear instructions, to make the installation and operation process smoother.

Energy Efficiency

– Tankless water heaters are generally more energy-efficient than traditional tank-style heaters, but some models may be more efficient than others.
– Consider the energy-saving features, such as on-demand heating and automatic shutoff, to maximize your energy savings.

FAQs

1. What is the main advantage of a tankless water heater over a traditional tank-style heater?
– Tankless water heaters provide instant hot water and are more energy-efficient, as they only heat water on demand, rather than keeping a large tank of water constantly heated.

2. How do I determine the right size tankless water heater for my bathtub?
– The size of the tankless water heater needed depends on the flow rate and temperature rise required for your bathtub. You can calculate this based on the size of your bathtub and your desired water temperature.

3. Can a tankless water heater be used for both a bathtub and a shower?
– Yes, many tankless water heaters are designed to handle the hot water needs of both a bathtub and a shower simultaneously, as long as the unit has sufficient power and flow rate.

4. How do I maintain a tankless water heater for optimal performance?
– Regular maintenance, such as flushing the unit to remove mineral buildup, following the manufacturer’s recommendations, and addressing any issues promptly, can help ensure your tankless water heater continues to perform at its best.

5. Can a tankless water heater be installed outdoors?
– Some tankless water heater models are designed for outdoor installation, while others are intended for indoor use only. Be sure to check the manufacturer’s specifications and installation requirements before attempting an outdoor installation.

Conclusion

Choosing the best tankless water heater for your bathtub can have a significant impact on your home’s hot water efficiency and convenience. By considering factors such as power, temperature control, safety features, and energy efficiency, you can find the perfect tankless water heater to meet your bathtub needs. With the information provided in this comprehensive review and buying guide, you’ll be well-equipped to make an informed decision and enjoy the benefits of instant, on-demand hot water for your bathtub.