To calculate the minimum circuit ampacity (MCA) for the rooftop unit, we need to take into account the full load amps (FLA) of both the compressor and the fans. Here's the step-by-step process:
1. Identify the given data:
- The compressor has a full load amps (FLA) of 20.
- There are two fans, each with a full load amps (FLA) of 2.5.
2. Combine the FLA of all fans:
- Since there are two fans with an FLA of 2.5 each, we calculate the total FLA for the fans:
[tex]\[ \text{Total FLA for fans} = 2 \times 2.5 = 5.0 \][/tex]
3. Sum the FLA of the compressor and the fans:
- Now, add the FLA of the compressor to the total FLA of the fans:
[tex]\[ \text{Total FLA} = 20 + 5.0 = 25 \][/tex]
4. Apply the MCA formula:
- The MCA formula generally takes into account a safety factor for start-up and other conditions. Based on the options given, we see that option C specifies multiplying the total FLA by 1.25:
[tex]\[ \text{MCA} = 1.25 \times \text{Total FLA} \][/tex]
[tex]\[ \text{MCA} = 1.25 \times 25 \][/tex]
5. Calculate the MCA:
- Finally, performing the multiplication gives us:
[tex]\[ \text{MCA} = 31.25 \][/tex]
Based on this detailed step-by-step calculation, the correct option is:
C. [tex]\( MCA = 1.25 \times (20 + 2.5 + 2.5) = 31.25 \)[/tex]
