Mizudo Electric Tankless Water Heater

1. Explanation of Symbols and Safety Instructions

This manual contains safety information and instructions to help you eliminate or reduce the risk of accidents and injuries.

1.1 Recognize Safety Information

The safety alert symbol ⚠️ can alert you to potential physical injury hazards. Obey all safety messages that follow this symbol to avoid possible injury or death.

1.2 Understand Signal Words

Signal words identify safety messages and property damage messages, and indicate a serious hazard:

• DANGER: Indicates an imminently hazardous situation which, if not avoided, will result in serious injury or death.
• WARNING: Indicates a hazardous situation that, if not avoided, could result in death or serious injury.
• CAUTION: Indicates a hazardous situation which, if not avoided, could result in property damage and minor or moderate injury.
• NOTICE: Indicates important information where there is no risk to people or property.

1.3 Important Safety Information

1. Installation must comply with the National Electrical Code, local electrical and plumbing codes.
2. This device must be grounded.
3. All wiring and installation must be supervised by a qualified electrician.
4. This product has multiple power connection points. Disconnect all power sources before servicing.
5. This appliance is not suitable for use by persons (including children) with reduced physical, sensory, or mental capabilities, or lack of experience and knowledge, unless supervised or instructed by a responsible person. Children should be supervised to ensure they do not play with electrical appliances.
6. The device must be permanently connected to a fixed circuit breaker and installed vertically. Do not install where there is fire or strong magnetic fields.
7. If the device may be frozen, do not open it; wait until it is completely defrosted before turning it on.
8. Before using, touch the hot water outlet temperature to ensure it is suitable and avoid scalding.
9. Before connecting pipes, flush them to remove any dirt or residue.
10. If the wire is damaged, contact a qualified electrician for replacement with a special wire from the authorized dealer.
11. For household and indoor use only.
12. Risk of electric shock exists if incorrectly connected; it must be connected to a circuit with ground protection.

⚠️ WARNING: This product can expose you to lead, known to the state of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.P65warnings.ca.gov.

2. General Information

2.1 Function Introduction and Explanation

This instant electric water heater uses Chinese national patent technology and features various safety devices. Key features include:

• No water storage tank, providing instant heating on demand, saving energy by eliminating preheating and heat loss.
• Microcomputer control technology with patented heating technology and multi-layer composite insulating materials to separate water and electricity.
• Over-temperature protection: If the outlet water temperature exceeds 149°F (65°C), the power cuts off, displaying E1. The device resumes automatically when the temperature drops.
• Sensor failure: If the inlet water temperature sensor fails, the heater stops and displays E3.
• To switch between Fahrenheit and Celsius, press and hold the heat up button when the appliance is powered on.

2.2 Dimensions and Connection Points

The unit has a Hot Water Outlet and a Cold Water Inlet. Key dimensions are:

• Width: 8.6" (218 mm)
• Height: 12.8" (328 mm)
• Depth: 2.3" (58 mm)
• Mounting hole spacing (vertical): 8" (204 mm)
• Mounting hole spacing (horizontal): 3.9" (100 mm)
• Connection port size: 1.6" (40 mm) from bottom edge.

2.3 Technical Parameters

2.4 Component Diagram

Front View Components:

• LED Display
• Control Key (with [+] and [Power/Switch] buttons)
• Front Cover

Internal Components:

• Thermostat
• Heating element
• Silicon controlled rectifier
• Controller
• Display assembly
• Power line
• Bottom case
• Hot water connection
• Cold water connection

3. Installation

3.1 Installation Instructions

Follow these instructions for safe and proper installation:

• Installation must comply with National Electrical Code, local electrical and plumbing codes.
• Ensure the product is intact and complete with accessories.
• Verify main power supply, water pressure, grounding conditions, ammeter, and wires meet requirements.
• The product must be installed in a circuit suitable for overcurrent and grounded at the breaker panel.
• Connect permanently to a fixed circuit breaker. If not using the heater, turn off the circuit breaker.
• Do not install in places with fire or strong magnetic fields. Install vertically. Connect to water first, then electricity.
• Avoid installing under water pipes or air conditioning lines that might leak.
• Do not install above electrical boxes or junctions.

⚠️ CAUTION: Locate the water heater away from areas where leakage could cause damage. If such areas are unavoidable, install a suitable, drained catch pan underneath.

3.2 Prepare for Installation

Parts included:

• Electric Tankless Water Heater
• Mounting Bracket
• User Manual
• Assembly Kit

Tools needed (Not included):

• Phillips screwdriver
• Slotted screwdriver
• Hammer Drill with Concrete Bits
• Ruler
• Gloves
• Pencil

3.3 Installation Method

⚠️ WARNING: Failure to follow these instructions may result in property damage, injury, or death, and void your warranty.

1. Find a suitable place to attach the water heater to the wall.
2. Use a screwdriver to remove the screws and separate the water heater from its mounting bracket.
3. Determine the mounting location, mark 3 mounting holes on the wall according to the mounting bracket or template.
4. Drill holes (e.g., 6mm diameter) at the marked locations. Insert 3-M4 rubber plugs into the holes.
5. Fix the supporting bracket horizontally onto the wall using 3-M4x25 screws.
6. Secure the product onto the bracket using a screwdriver.
7. Connect the power cord.

3.4 Plumbing Installation

1. All water pipes must comply with national and local codes.
2. Connect the unit directly to the main water supply. Flush pipes with water to remove debris before connecting to avoid clogging.
3. The water heaters require a 1/2" NPT water connection.
4. Flexible water hoses are recommended for easier maintenance. Ensure rubber seal rings are installed at connections. Check for leaks after completing all water connections.
5. Install service valves at the inlet and outlet fittings, especially in hard water areas, for easier annual maintenance.

3.5 Electrical Connections

1. Complete all mounting and plumbing before electrical hook-up.
2. All electrical work must comply with national and local electrical codes.
3. The unit must be connected to a properly grounded, dedicated branch circuit of the correct voltage rating.
4. Before any electrical work, ensure the main breaker switch is OFF to prevent electric shock.
5. When connecting wires to the panel breaker, ensure metal wire ends and blocks make complete contact. Tighten screws securely.
6. Always turn off the circuit breaker for the water heater before installing, disassembling, or repairing it.

Electrical Connection Diagrams:

• ET006 (240V): Connects to a double pole circuit breaker. Wires: Black to breaker (power), Red to breaker (power), Green/Yellow to ground bar.
• ET003 (120V): Connects to a one-pole breaker. Wires: Black to breaker (power), White to neutral, Green to ground bar.

⚠️ WARNING: When connecting the power cord, the power must be turned off.

4. Operation

4.1 Operation Instructions

⚠️ WARNING: Do not store or use gasoline or other flammable vapors and liquids near this or any other appliance.

1. Turn on the water faucet for a few minutes until water flow is constant and all air is expelled.
2. Turn on the circuit breaker to supply power. The appliance will beep and enter standby mode.
3. Press the Switch button [Power] to start the unit.
4. Press the [+] or [-] buttons to adjust the water temperature. The setting range is 80-130°F (26-55°C).

Display Indicators:

• (1) Water flow signal
• (2) Water is heating up indicator
• (3) Heat up button [+]
• (4) Heat down button [-]
• (5) Outlet water temperature display
• (6) Fahrenheit indicator
• (7) Celsius indicator
• (8) Switch button [Power]

5. Maintenance

Function Description

• Screen protection: Enters screen saver mode after 30 seconds of no water flow or key operation. Screen wakes up with flow or operation key.
• Temperature unit switching: Press and hold [+] to switch between Fahrenheit and Celsius when powered on.
• Power failure memory function: Retains the last set temperature after power restoration.
• If the unit was paused, a short burst of very hot water may occur initially. Run water for a few seconds to stabilize temperature. Always check hot water temperature before use.
• If not used in winter, drain the water completely to prevent freezing.
• Clean the inlet filter periodically to maintain proper water flow.

⚠️ WARNING: Minors are not allowed to operate the water heater themselves unless accompanied by a guardian.

Maintenance Recommendations

⚠️ CAUTION: Do not attempt self-repair. Call a technician. Always shut off the power supply before performing maintenance.

To ensure consistent performance:

1. Periodically remove scales and dirt from the faucet aerator.
2. Clean the built-in inlet filter at the connection point from time to time. Cut off water supply before cleaning.
3. If you live in a hard water area, consider installing a descaling device. It is recommended to annually change the filter for the descaling device or follow its manufacturer's instructions.

Important Notes:

• Maintenance may introduce air into plumbing pipes; purge all air before powering on again.
• For hard water supplies, increase maintenance frequency and check the descaling device regularly.
• Clean the unit with a damp cloth and mild detergent only. Do not use thinners, alcohol, petrol, or other organic solutions.

6. Troubleshooting

6.1 Diagnostic Codes

6.2 Fault Assessment and Troubleshooting

7. Circuit Diagram

ET003 Circuit Diagram:

Shows connections for Ground (G), Line (L), and Neutral (N) to a Triac, Display board, and Heating element.

ET006 Circuit Diagram:

Shows connections for Ground (G), Line 1 (L1), and Line 2 (L2) to a Triac, Display board, and Heating element.

8. Packing List

9. Warranty Policy

What is covered

The Standard Limited Warranty covers defects in materials or workmanship when the product is installed and operated according to Mizudo's written instructions, within the United States and Canada. Improper installation may void the warranty. Mizudo recommends installation by a licensed, state-qualified, and trained contractor.

How long does coverage last

*Excludes Alaska, Hawaii, and locations outside the continental US and Canada.

Limitation on warranties

During the warranty period, only genuine Mizudo parts and qualified professionals should perform repairs. Mizudo will repair, replace, or refund at its sole discretion. Mizudo is not liable for obligations assumed by others. Warranty claims may be denied for defects not found, or for damage caused by improper installation, use, or operation. No other warranties are expressed or implied. Implied warranties are limited to the duration of this Limited Warranty. Mizudo is not liable for indirect, incidental, special, consequential, or other similar damages.

How To Obtain Service

Contact Mizudo's Customer Service team at us.mizudo@fogatti.com, schedule a call, or use Mizudo Whatsapp for warranty claims. Returns for refund require prior approval. Mizudo covers ground shipping for warranty issues in the US/Canada for the first 30 days; owner is responsible thereafter. Mizudo covers return shipping after repair/inspection. Required information for claims includes proof of purchase, serial numbers, and photos of installation/damage. All shipments must have a Return Goods Authorization (RGA) number. Returns must be in original packaging; missing components may incur a 15% restock fee.

What Is Not Covered

This Limited Warranty does not cover:

• Products not properly installed and maintained per manuals and codes.
• Abuse, misuse, alteration, neglect, or misapplication.
• Services performed by third-party providers.
• Expenses for labor services (installation, removal).
• Damage from improper installation (sizing, elevation, airflow).
• Damage from improper use (freezing, scaling, incorrect pressure).
• Use as a pool or spa heater.
• Damage from non-potable, untreated, or high-pH/hardness water.
• Products with removed or altered serial numbers.
• Increases in electricity costs.
• Defaults or delays caused by factors outside Mizudo's control.