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MAXKOSKO Official Guide: Resolving E1 & E2 Sensor Errors

MAXKOSKO Official Guide: Resolving E1 & E2 Sensor Errors

This official guide explains the E1 (Internal Sensor) and E2 (External Sensor) error codes on MAXKOSKO thermostats. Follow our step-by-step troubleshooting for wiring and resistance testing to resolve these issues quickly and safely.

At MAXKOSKO, we design our thermostats to keep your home comfortable and your heating system safe. If your display shows an E1 or E2 error code, the device has detected a sensor-related issue that needs attention.

This guide will help you understand these codes and provide a step-by-step checklist to restore your floor heating system.

Understanding the Codes

What Does E1 Mean? (Internal Room Sensor)

The E1 code indicates an issue with the thermostat's built-in air temperature sensor.

Potential Cause: The internal sensor may be damaged or exposed to extreme temperatures outside the device's operating range.

What to do: E1 is usually an internal hardware issue. Please try restarting the device by turning the power off and on at the circuit breaker. If the code persists, contact our support team for warranty assistance.

What Does E2 Mean? (External Floor Sensor)

The E2 code is much more common and relates to the External Floor Sensor Probe installed under your flooring. An E2 code does not necessarily mean your MAXKOSKO thermostat is faulty; it often means the thermostat cannot "find" or "read" the sensor properly.

Step-by-Step Troubleshooting for E2 Errors

If you see E2, follow these professional steps to identify the problem:

1. Inspect the Wiring Connections

Turn off the power and check the sensor terminals (usually marked as 'Sensor' or 'S') on the back of the thermostat.

Loose Wires: Ensure the wires haven't slipped out due to vibration or tension.

The "Insulation Trap": This is a frequent installation error. Ensure the terminal screw is clamping down on the metal copper conductor, not the plastic insulation. If the screw is holding the plastic, the electrical circuit is broken, causing an E2 error.

2. Verify Wire Stripping

Properly stripped wires are essential. Ensure that about 8-10mm of insulation has been removed, providing a clean contact point for the terminal.

3. Check Thermostat Settings

MAXKOSKO thermostats are highly compatible. If you are using a sensor from a different brand, you must ensure the correct sensor type is selected in the Advanced Settings (e.g., 10k, 12k, or 15k Ohms).

Access the menu to confirm that the sensor mode is set to "OUT" (External) or "ALL" (Both) and that the resistance matches your probe.

4. Test the Sensor Resistance

If the wiring looks perfect but E2 remains, use a multimeter to test the floor sensor's resistance:

Reading of 0 Ohms: Indicates a short circuit in the sensor wire.

Reading of OL (Open Loop): Indicates the wire is cut or disconnected.

Expected Reading: For a standard MAXKOSKO sensor, you should see approximately 10k Ohms at room temperature (25 degrees Celsius).

Still Need Help?

If you have followed these steps and the E2 error persists, the sensor probe itself may be damaged.

For users with older models looking for the latest features and improved sensor compatibility, consider upgrading to our latest MAXKOSKO Smart Thermostat. Our newest version offers enhanced stability and easier setup to prevent these issues from recurring.

Need Technical Support? Our team is here to help you get your floor heating back on track. Contact us via our official website with your order number and a photo of your wiring for expert assistance.

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