FC Load Calculations & Equipment Sizing 2

Question 1

What is a common negative consequence of installing an oversized furnace in a residence?

Accepted Answer

Short cycling, leading to reduced comfort and increased wear

Answer

An oversized furnace heats the space too quickly and short cycles, which reduces comfort through uneven temperatures, increases mechanical wear, and lowers overall efficiency.

Question 2

Which ACCA manual provides guidance specifically for residential duct system design?

Accepted Answer

Manual D

Answer

ACCA Manual D is the standard for designing residential duct systems, ensuring proper airflow to match the calculated loads from Manual J.

Question 3

What is the maximum recommended oversizing percentage for a gas furnace according to ACCA Manual S guidelines?

Accepted Answer

40%

Answer

ACCA Manual S generally allows gas furnaces to be oversized by up to 40% of the calculated heating load to account for setback recovery and future needs.

Question 4

A home has a calculated design heating load of 60,000 BTU/h. Which furnace output capacity is the most appropriate selection?

Accepted Answer

80,000 BTU/h output

Answer

An 80,000 BTU/h output furnace represents a 33% overage over the 60,000 BTU/h load, which falls within the ACCA Manual S acceptable range for gas furnaces.

Question 5

How does a home's infiltration rate affect the heating load calculation?

Accepted Answer

Higher infiltration increases heating load by introducing cold outside air

Answer

Higher infiltration brings more unconditioned cold outside air into the building, increasing the heating energy required to bring that air up to the design temperature.

(FC) Furnace Installation and Maintenance Certification Practice Test

(FC) Furnace Installation and Maintenance Certification Practice Test

FC Load Calculations & Equipment Sizing 2