What is the best under cabinet tankless water heater?

Quick Answers

When looking for the best under cabinet tankless water heater, there are a few key factors to consider:

– Flow rate – Tankless heaters are rated by maximum flow rate in GPM (gallons per minute). Under cabinet models usually range from 1.5-6 GPM. Choose a model with a flow rate to meet your needs.

– Power – Tankless heaters run on electricity, propane, or natural gas. Under cabinet models are usually electric. Make sure to choose a model with sufficient power in watts for your requirements.

– Size – Under cabinet models must fit in the limited space available. Measure to ensure the dimensions meet your cabinet size.

– Ease of installation – Under cabinet heaters use simpler wall mounts or brackets for easier DIY installation vs whole home models.

– Price – Under cabinet tankless heaters range from $150 on the low end to $500+ for higher end options with WiFi, touchscreens, etc. Set a budget and choose accordingly.

What are the Benefits of Under Cabinet Tankless Water Heaters?

Under cabinet tankless water heaters offer several benefits compared to conventional tank water heaters:

– Endless hot water – Tankless heaters only heat water on demand, so you’ll never run out of hot water. Great for households with peak usage times.

– Energy efficient – You’re only heating water as needed, rather than keeping a tank hot 24/7. This saves on energy costs.

– Compact size – Tankless models are much smaller than tank heaters, making them ideal for under cabinet installation.

– Long lasting – Tankless heaters can last up to 20 years vs 10-15 years for tank models. The lack of a tank means no corrosion issues.

– Lower operating costs – The combination of endless hot water and higher efficiency means tankless heaters can save $100 or more per year in energy costs.

– Simple installation – Under cabinet heaters use simpler mounting hardware and plug into a standard outlet for easier DIY install vs whole home models.

Where are Under Cabinet Tankless Water Heaters Used?

The main uses for under cabinet tankless water heaters include:

– Small kitchens – For apartments, vacation homes, or anywhere with a compact kitchen, an under cabinet model provides hot water without taking up much space.

– Remote sinks – For a bathroom or sink far from the main water heater, an under cabinet tankless model provides instant hot water on demand.

– Bosch dishwasher – Bosch dishwashers can connect to a point-of-use tankless heater for a boost in cleaning performance.

– Outdoor kitchens – For an outdoor sink or kitchen, a small electric tankless model can be used instead of running hot water lines.

– Office breakrooms & wet bars – An under cabinet tankless heater allows offices and wet bars to have an endless hot water supply for sinks, coffee, tea, etc.

– Hair salons – To provide ample hot water at shampoo bowls, salons often use multiple point-of-use tankless heaters.

How Does an Under Cabinet Tankless Water Heater Work?

Under cabinet tankless water heaters work a bit differently than conventional storage tank heaters:

– Cold water flows into the unit when the hot water tap or valve is opened.

– An electrical current or gas burner is activated which heats a copper heat exchanger inside the unit.

– The cold water passes through the heat exchanger and is rapidly heated to the set output temperature.

– A flow valve or sensors ensure the burner activates only when hot water is needed.

– The heated water is instantly sent to the sink, appliance, etc.

– When the tap is turned off, the unit shuts off the heating elements immediately.

– No water is stored inside the tankless unit. Heat is generated on demand via the heat exchanger.

So in summary, tankless heaters create hot water in real-time as you need it vs heating and storing hot water 24/7 like tank models. This gives you endless hot water plus energy savings.

How to Size an Under Cabinet Tankless Water Heater

Properly sizing an under cabinet tankless water heater involves 3 key factors:

1. Hot water flow rate needed – First, estimate your peak hot water requirements in gallons per minute (GPM). Typical kitchen sinks use 1.5-2.5 GPM.

2. Temperature rise – Next, determine the difference between incoming cold water temp and desired hot water temp. A typical rise is 90-120°F.

3. Heating capacity – Using the GPM flow rate and temp rise, select a heater with sufficient heating capacity in kW to heat that volume of water.

As an example – for a kitchen sink needing 2 GPM flow and with a 100°F temp rise (50°F to 150°F), you would need a heater with at least 20,000 BTU or 6 kW heating capacity.

When in doubt, size up. It’s better to have too much heating power than not enough. Check manufacturer sizing guides for any specific product.

Where to Install an Under Cabinet Tankless Water Heater

The ideal installation location for an under cabinet tankless water heater is:

– Below the main kitchen sink or other sink where hot water is needed.

– Mounted to the cabinet wall framing studs for optimal support.

– Close to the incoming cold and hot water supply lines for simplest plumbing.

– With proper clearances from combustibles if powered by propane or natural gas.

– In a weather protected location for outdoor installations.

– With proper electrical outlet if an electric powered model.

– With adequate ventilation according to manufacturer requirements.

– Following all local building codes and permitting requirements.

You’ll want easy access to the unit for any future maintenance or settings adjustments. Leaving the front cover clear of obstructions is recommended.

How to Install an Under Cabinet Tankless Water Heater

Installing an under cabinet tankless water heater involves the following key steps:

1. Turn off water supply valves and power.

2. Select mounting location per previous section guidelines.

3. Measure and cut holes for penetrating water lines if needed.

4. Secure mounting bracket hardware to cabinet framing.

5. Mount the tankless unit to the bracket.

6. Connect hot and cold water supply lines to the tankless unit.

7. Connect a discharge line from the tankless heater to the sink.

8. Plug in the power cord or connect gas/propane lines if applicable.

9. Turn on water supply and check for leaks.

10. Turn on power and verify correct operation. Adjust temperature setting as desired.

Always consult the manufacturer installation guide for complete instructions. Consider hiring a professional plumber for optimal safety and results.

Maintenance Tips for Under Cabinet Tankless Water Heaters

To keep an under cabinet tankless water heater running smoothly:

– Flush the heat exchanger annually to prevent mineral buildup. Use a descaling solution for electric models.

– Change the water filter annually or per manufacturer specs to remove scale-causing particles.

– Keep the unit free of dust and debris which can impede airflow. Wipe down with a damp cloth.

– Check for water leaks and corrosion in water lines. Repair any issues immediately.

– For gas models, inspect the burners annually and clear any obstructions, dirt, or debris.

– Verify the exhaust vent or flue remains properly installed and unobstructed.

– Inspect electrical connections to ensure no damage or loosening of wires. Tighten as needed.

– Test operation and safety systems according to manufacturer guidelines.

Following proper maintenance procedures will extend the life of your under cabinet tankless water heater.

Troubleshooting Common Under Cabinet Tankless Water Heater Problems

Problem	Possible Causes	Solution
Not enough or no hot water	Clogged heat exchanger, High water flow, Bad sensors, Insufficient power	Flush heat exchanger, Reduce water flow, Test/replace sensors, Upsize heater
Water is too hot	Faulty thermostats, Out of adjustment	Replace thermostats, Recalibrate temperature
Leakage from unit	Loose fittings, Corrosion, Cracks	Inspect and tighten fittings, Check for cracks, Replace leaky parts
Burner won’t ignite	Clogged gas lines, Bad igniter	Clean gas lines, Replace igniter
Noise and abnormal sounds	Lime buildup, Damaged blower fan, Vibration	Flush with descaling solution, Replace blower fan, Tighten loose parts

Consult troubleshooting guides to diagnose issues. Contact technical support for further assistance.

Reviews of the Top Under Cabinet Tankless Water Heaters

To help narrow down the choices, here are reviews of 5 top rated under cabinet tankless water heater models:

Brand & Model	Highlights	Specs	Average Rating
Ecosmart ECO 18	Most affordable, simple controls, fast heating	18 kW power, 1.5 GPM	4.5 / 5
Camplux ME40	Compact, easy installation, good temp control	14 kW, 2.64 GPM	4.4 / 5
Eccotemp L5	Great value, high flow rate, LCD display	20 kW, 5 GPM	4.7 / 5
Stiebel Eltron Tempra 24	Advanced temperature controls, very durable	24 kW, 6 GPM	4.8 / 5
Chronomite SR-20L	Lots of power, touchpad controls, 10 year warranty	20 kW, 6 GPM	4.9 / 5

As you can see, there are good choices at varying price points and specs. The Chronomite SR-20L is the top pick for a powerful, higher end unit. The Ecosmart ECO 18 provides great value for smaller needs. Choose the right size and features for your requirements.

Conclusion

Installing an under cabinet tankless water heater is a great way to save space, energy, and money while supplying endless hot water. Carefully consider your needed flow rate, power options, and dimensions to select the right model. Following proper installation and maintenance best practices will ensure optimal performance and satisfaction. Brands like Ecosmart, Camplux, Eccotemp, Stiebel Eltron and Chronomite offer quality under cabinet tankless heaters at reasonable prices. With a little planning, you can enjoy hot water convenience from your new unit for years to come. Let us know if you have any other questions!