Load Calculation and Blueprints Flashcards

What does a 'U-factor' (U-value) measure in building envelope load calculations?

Answer: Rate of heat transfer through a building assembly

The U-factor measures how readily heat flows through a building assembly; it is the inverse of R-value (U = 1/R).

On a set of construction drawings, which sheet typically contains notes about duct insulation requirements and equipment specifications?

Answer: Mechanical specification sheet or general notes sheet

Mechanical specification or general notes sheets list material requirements, equipment specs, and installation standards for HVAC systems.

What is the purpose of applying a 'safety factor' or equipment oversizing limit in residential load calculations?

Answer: To prevent excessive short cycling while ensuring comfort

Limiting oversizing prevents short cycling, which reduces dehumidification ability, comfort, and equipment lifespan.

Which term describes the amount of moisture in the air relative to the maximum it can hold at a given temperature?

Answer: Relative humidity

Relative humidity expresses the ratio of actual moisture in the air to the maximum possible moisture at that temperature, as a percentage.

On blueprints, what information is typically found in the title block?

Answer: Project name, sheet number, scale, and revision history

The title block contains essential identification information including the project name, drawing title, scale, sheet number, and revision dates.

When calculating latent heat loads, which source contributes the most latent load in a typical residential kitchen?

Answer: Cooking appliances and occupants

Cooking appliances release significant steam and moisture, and occupants also produce latent heat through perspiration and respiration.

What does the abbreviation 'OA' stand for on HVAC blueprints?

Answer: Outside Air

OA stands for Outside Air, referring to fresh air drawn from outdoors into the HVAC system for ventilation.