CRD Residential Energy Efficiency & Load Calculations 2

Question 1

Which method is most commonly used for residential cooling load calculations in geothermal system design per ACCA standards?

Accepted Answer

Manual J

Answer

Manual J by ACCA is the industry-standard residential load calculation method used to size geothermal and other HVAC systems.

Question 2

A house has a design heating load of 48,000 BTU/hr. If a geothermal heat pump has a COP of 3.5, what is the approximate electrical input required?

Accepted Answer

13,714 BTU/hr (4.02 kW)

Answer

Electrical input = 48,000 / 3.5 ≈ 13,714 BTU/hr; dividing by 3,412 BTU/kWh gives approximately 4.02 kW.

Question 3

In residential load calculations, infiltration is typically measured using which unit?

Accepted Answer

ACH (air changes per hour)

Answer

Infiltration in residential buildings is expressed as ACH (air changes per hour), representing how many times the home's air volume is replaced by outdoor air.

Question 4

Which insulation metric directly describes how well a material resists heat flow per inch of thickness?

Accepted Answer

R-value per inch

Answer

R-value per inch (specific R-value) describes a material's thermal resistance per unit thickness, enabling comparison between insulation types.

Question 5

The Design Temperature Difference (DTD) used in heat loss calculations is defined as:

Accepted Answer

Indoor design temperature minus the outdoor design dry-bulb temperature

Answer

DTD = indoor setpoint (typically 70°F) minus the outdoor winter design temperature, representing the worst-case temperature difference driving heat loss.

(CRD) Certified Residential Geothermal Designer Practice Test

(CRD) Certified Residential Geothermal Designer Practice Test

CRD Residential Energy Efficiency & Load Calculations 2