Air Conditioning Repair Heat Load Calculations and System Sizing 3

Question 1

A home requires 36,000 BTU/hr of cooling capacity. What is the correct equipment size in tons?

Accepted Answer

3 tons

Answer

2 tons

Answer

2.5 tons

Answer

3.5 tons

Question 2

What happens when an air conditioning system is undersized relative to the building's peak cooling load?

Accepted Answer

It runs continuously but cannot maintain the desired setpoint on peak days

Answer

It short cycles and removes excess humidity

Answer

It operates more efficiently due to longer run times

Answer

It causes refrigerant slugging in the compressor

Question 3

Which software platform is widely used by HVAC contractors to perform Manual J residential load calculations?

Accepted Answer

Wrightsoft Right-Suite

Answer

AutoCAD Architecture

Answer

QuickBooks Desktop

Answer

Microsoft Visio

Question 4

In load calculations, the U-value of a building assembly describes which property?

Accepted Answer

The overall heat transfer coefficient of the assembly

Answer

The thermal resistance of the insulation layer

Answer

The solar absorptance of the exterior surface

Answer

The air leakage rate through the assembly

Question 5

What does the ventilation load component account for in an HVAC load calculation?

Accepted Answer

Conditioning intentionally introduced outdoor fresh air

Answer

Air movement losses through supply and return ductwork

Answer

The energy required to size supply and return registers

Answer

Static pressure drop across the air handler

Question 6

In a multi-zone HVAC system, how should each zone's equipment or airflow capacity be determined?

Accepted Answer

Size each zone for its own peak cooling demand

Answer

Divide the total building load equally among all zones

Answer

Use the average load across all zones for uniformity

Answer

Apply the largest zone's load to every zone as a safety factor

Question 7

What does the 'diversity factor' account for in commercial HVAC load calculations?

Accepted Answer

The recognition that not all loads peak simultaneously, allowing reduced total system capacity

Answer

The variety of refrigerants approved for use in the system

Answer

The range of outdoor temperatures the system must handle throughout the year

Answer

The number of different mechanical zones within the building