A project involves installing a new air handler to serve an existing office space. The existing mechanical equipment is being reused. According to the California Mechanical Code, what is the minimum MERV rating required for the filters in this system?

• The code does not specify a minimum MERV rating for this scenario due to the exception for existing equipment.
• MERV 8, as it is a common standard for existing systems.
• MERV 13, but only for the outside air filters; return air filters can be MERV 8.
• MERV 13, as it is required for all new installations.