Error Code H4Updated a year ago
What to do if Mysa shows an H4 Error Code
An H4 error can indicate an installation issue such as mis-wiring, or exceeding the maximum amperage and wattage limits of the Mysa device.
If this error occurs, please try to reboot your Mysa thermostat first - if the error clears you can continue operating Mysa as normal.
Rebooting Mysa
It is important to try to clear the error by rebooting the Mysa. Some errors are very rare and may only be seen once. In these cases, it is not necessary to perform any additional actions.
For Mysa for Baseboard Heaters, this can be done by
Removing the faceplate on your Mysa. Follow the steps below:
Unscrew the faceplate - there’s a small screw at the bottom of your Mysa.
Carefully slide off the faceplate.
Keep it unattached for 5-10 minutes.
Carefully reattach the faceplate. Be careful not to bend the pins that connect it to the base of your Mysa!
Your Mysa will take a few seconds to reboot.
- Flipping the breaker controlling your Mysa OFF, waiting around 30 seconds, and flipping it back ON.
Warning! High Voltage!!
Any work with high voltage equipment can be dangerous or even fatal if you do not take proper precautions. You should never work with live wires.
If this error does not clear please:
Power your Mysa thermostat down at the breaker.
Ensure that the wire nuts are tightly fastened to the wires. Lightly tug the connected wires on each side. The wires should not come loose with a tug.
Contact Mysa Support - [email protected] as soon as possible for additional assistance.
Send us a photo of how this unit is installed. The photo should include the wiring coming from within your gang box and how they are connected to Mysa.
Additionnaly, please provide the following information:
The number of heaters connected to this unit.
The wattage of each heater.
A photo of the back of the faceplate showing the unit’s serial number.
Your order number or proof of purchase.
If you wish, you can replace the Mysa with your old thermostat while awaiting assistance.