Celsius heat units (IT) per hour to milliwatts conversion calculator above calculates how many milliwatts are in 'X' Celsius heat units (IT) per hour (where 'X' is the number of Celsius heat units (IT) per hour to convert to milliwatts). In order to convert a value from Celsius heat units (IT) per hour to milliwatts (from CHU/h to mW) type the number of CHU/h to be converted to mW and then click on the 'convert' button.