The Moducontrol shuts off the compressor and condenser fan motors when the defrost mode starts. The Moducontrol then stops the compressor and switches the position of the reversing valve to warm the outdoor coil. The compressor is then turned back on. The ice and frost build up on the outdoor coil melts and drains away. The Moducontrol then stops the compressor and switches the position of the reversing valve to the heating mode. The compressor resumes in the heating mode after the time delay is completed. The system water pump runs all the time through the defrost process.
