Methods and devices for controlling the temperature of a surface

A method for controlling the temperature of a surface using a thermal adjustment device, the method comprising:

• applying a variable input to a heat pump of the thermal adjustment device in thermal communication with the surface;
• measuring, by the thermal adjustment device, a temperature of an element in thermal communication with the surface;
• determining, by the thermal adjustment device based on the temperature of the element, whether a temperature of the surface is within a safe temperature range for a user in thermal communication with the surface;
• in response to determining the surface is not within the safe temperature range, adjusting, by the thermal adjustment device, a voltage of the variable input to the heat pump;
• and
• in response to determining the surface is within the safe temperature range, continuing, by the thermal adjustment device, operation of the variable input at the voltage, wherein:
• the heat pump is configured to operate in at least a first mode and a second mode,
• when the heat pump operates in the first mode, the safe temperature range comprises a first temperature range, and
• when the heat pump operates in the second mode, the safe temperature range comprises a second temperature range different from the first temperature range.