ThermoMate ES400 4 Gallon Mini Tank Electric Water Heater Instruction Manual

1. Product Overview

The ThermoMate ES400 is a compact 4-gallon mini tank electric water heater designed for point-of-use applications, providing instant hot water. It features an Incoloy 800 stainless steel heating element for corrosion resistance and high efficiency, and an enamel-coated glass-lined tank for insulation and leak prevention. This unit is UL certified, ensuring safety and a long service life.

Image 1: Front view of the ThermoMate ES400 Mini Tank Water Heater, showing the temperature control dial and indicator light.

2. Safety Information

Please read and understand all instructions before installing and using this water heater. Failure to follow these instructions may result in property damage, serious injury, or death.

• Electrical Safety: Ensure the unit is properly grounded. Disconnect power before performing any service or maintenance.
• Hot Water Hazard: Water temperatures above 125°F (52°C) can cause severe burns or scalding. Exercise caution when setting the temperature.
• Pressure Relief Valve: A temperature and pressure (T&P) relief valve is supplied and must be installed. Do not operate the water heater without a properly installed T&P relief valve. Ensure the discharge line from the T&P valve is directed to a suitable drain.
• Water Leaks: Regularly inspect the unit for any signs of water leakage. Address leaks immediately to prevent property damage.

Image 2: Close-up of safety labels on the water heater, indicating caution for hot water and the importance of the T&P relief valve.

3. Installation

The ThermoMate ES400 can be wall-mounted or floor-mounted under a sink or counter. It plugs into a standard 120V outlet.

3.1 Unboxing and Components

Carefully remove the water heater and all accessories from the packaging. Verify all components are present:

• ThermoMate ES400 Water Heater
• Instruction Manual
• Mounting Kits (screws, anchors, bracket)
• Pressure Relief Valve (CSA T&P Relief valve CASH USA made)

Image 3: Contents of the ThermoMate ES400 packaging, including the water heater, instruction manual, mounting kits, and pressure relief valve.

3.2 Mounting the Unit

The unit can be mounted on a wall or placed on the floor. For wall mounting, ensure the mounting surface is sturdy enough to support the weight of the unit when full (approximately 33 lbs for 4 gallons).

1. Identify a suitable location for the water heater, ensuring adequate clearance for plumbing and electrical connections.
2. For wall mounting, use the provided mounting bracket. Secure the bracket to wall studs or use appropriate anchors for drywall. It is recommended to mount a 2x4 piece of wood across two studs for added support, especially for heavier tanks.
3. Lift the water heater and carefully hang it onto the mounted bracket.

3.3 Water Connections

The water heater has 1/2" NPT connections for both cold water inlet and hot water outlet.

1. Apply Teflon tape to the threads of all connections to ensure a watertight seal.
2. Connect the cold water supply line to the blue-colored inlet on the top of the unit.
3. Connect the hot water outlet line to the red-colored outlet on the top of the unit.
4. Install the provided T&P relief valve into the yellow-colored port. Ensure the discharge line is routed to an appropriate drain, visible for inspection.
5. Once all connections are secure, slowly open the cold water supply valve to fill the tank. Allow air to escape from the hot water faucet until a steady stream of water flows, indicating the tank is full.

Image 4: Diagram showing the cold water inlet, hot water outlet, and T&P relief valve connections on the water heater.

3.4 Electrical Connection

The water heater requires 1.44 kW at 120 volts and comes with a 2-foot power cord for plug-in connection. Nominal current is 12 amps.

1. Ensure the tank is completely filled with water before connecting to power.
2. Plug the power cord into a standard 120V outlet.
3. The indicator light on the unit will illuminate when heating.

4. Operating Instructions

The ThermoMate ES400 features an adjustable temperature range from 50°F to 149°F.

1. Power On: Ensure the unit is plugged into a live electrical outlet.
2. Set Temperature: Rotate the temperature control dial on the front of the unit to your desired hot water temperature. The indicator light will turn on when the unit is actively heating.
3. Initial Heating: For the first use, allow approximately 15 minutes for the tank to heat cold water to the set temperature.

Image 5: Close-up of the temperature control dial on the ThermoMate ES400, showing the adjustable range.

5. Maintenance

Regular maintenance ensures optimal performance and extends the lifespan of your water heater.

5.1 Anode Rod Inspection and Replacement

The anode rod protects the tank from corrosion. It should be inspected annually and replaced if significantly depleted.

1. Disconnect power to the water heater at the circuit breaker.
2. Turn off the cold water supply to the unit.
3. Drain a small amount of water from the tank to relieve pressure.
4. Remove the front access panel (secured by two small Phillips head screws hidden under rubber grommets).
5. Carefully disconnect the wiring from the heating element.
6. Unscrew the heating element assembly (typically 10mm nuts) and carefully pull it out. The anode rod is attached to this assembly.
7. Inspect the anode rod for corrosion. If it is less than 1/2 inch thick or more than 6 inches of core wire is exposed, it needs replacement.
8. Replace the anode rod if necessary, ensuring a tight but not overtightened seal.
9. Reassemble the heating element, wiring, and front panel.
10. Refill the tank with water and check for leaks before restoring power.

5.2 Draining the Tank

If the unit needs to be moved or stored in an area where it might freeze, it must be drained completely.

1. Disconnect power to the water heater.
2. Turn off the cold water supply.
3. Open a hot water faucet in your sink to allow air into the tank.
4. Connect a hose to the drain valve at the bottom of the water heater and direct it to a suitable drain.
5. Open the drain valve and allow the tank to empty completely.

6. Troubleshooting

If you experience issues with your water heater, refer to the following common troubleshooting steps:

• No Hot Water: Check if the unit is plugged in and the circuit breaker is not tripped. Ensure the temperature dial is set above the current water temperature.
• Insufficient Hot Water: Verify the temperature setting is adequate. Ensure the cold water supply valve is fully open.
• Leaking: Immediately turn off the water supply and power. Inspect all connections for tightness. Check the T&P relief valve for discharge. If the leak persists, contact customer service.
• T&P Valve Discharge: If the T&P valve is frequently discharging, it may indicate excessive pressure or temperature. Do not block the discharge line. Contact a qualified plumber or customer service.

7. Specifications

8. Warranty & Support

The ThermoMate ES400 comes with a 3-year warranty. For customer service and support, please refer to the contact information provided in your product packaging or visit the official ThermoMate website.

24-hour customer service is available to assist with any inquiries or issues.