Prevent temperature conversion for a particular sensor?

I report CPU (and GPU temperature via an MQTT broker. The incoming message looks like

CM/polana/temperature/CPU,GPU 1628262001, 51.540, 51.5

I’m extracting the CPU temperature using the following sensor entry in configuration.yaml

  - platform: mqtt
    state_topic: "CM/polana/temperature/CPU,GPU"
    unique_id: "polana_temp"
    unit_of_measurement: "°C"
    value_template: "{{ value.split(',')[1] }}"

This works as desired except that it converts the temperature to °F. I’m in the US and °F is correct for most of my displays, but for some like CPU temperature I’m accustomed to seeing them in °C. Is there a way to prevent conversion of particular sensors?