Technician hat (A) says that the manual -tyne HVAC system is the most basic type of system. Tecinician B says that a scan tool should be used to diagnose a manual-type HVAC system. Who is correct? a. Technician A b. Technician B c. Both Technician A and Technician B d. Neither Technician A nor Technician B

## Step 1<br />Technician A states that the manual-twine HVAC system is the most basic type of system. This statement is correct. A manual-twine HVAC system is indeed the most basic type of system. It operates manually, without the use of a thermostat or other automatic controls.<br /><br />## Step 2<br />Technician B suggests that a scan tool should be used to diagnose a manual-type HVAC system. This statement is incorrect. A scan tool is typically used for diagnosing electronic or computer-controlled systems, not manual systems. Manual HVAC systems do not have the electronic components that a scan tool would interface with.