HERS HERS HVAC Systems and Equipment Evaluation 1 — Questions and Answers
Question 1: What AFUE rating is the minimum threshold for a gas furnace to be considered high-efficiency under current U.S. energy standards?
- 78%
- 80%
- 90% (Correct answer)
- 95%
Correct answer: 90%
A gas furnace must have an AFUE of 90% or higher to be classified as high-efficiency under U.S. standards.
Question 2: Which metric is used to rate the cooling efficiency of central air conditioning systems on the HERS rating?
- EER
- SEER (Correct answer)
- COP
- HSPF
Correct answer: SEER
SEER (Seasonal Energy Efficiency Ratio) is the primary metric used to evaluate central air conditioner efficiency in HERS ratings.
Question 3: When a HERS rater verifies equipment sizing, which method is the industry-accepted standard for performing residential load calculations?
- ACCA Manual J (Correct answer)
- ASHRAE 90.1
- RESNET Chapter 3
- IECC Table R403
Correct answer: ACCA Manual J
ACCA Manual J is the industry-accepted protocol for calculating residential heating and cooling loads.
Question 4: What is the minimum HSPF rating required for an air-source heat pump to qualify as high-efficiency?
- 6.8
- 7.7
- 8.2 (Correct answer)
- 10.0
Correct answer: 8.2
An HSPF (Heating Seasonal Performance Factor) of 8.2 or higher qualifies an air-source heat pump as high-efficiency.
Question 5: In REM/Rate energy modeling, how is a heat pump water heater typically entered to reflect its efficiency correctly?
- As a standard electric resistance unit with adjusted EF
- Using the Uniform Energy Factor (UEF) from the EnergyGuide label (Correct answer)
- As a solar thermal unit with backup
- Using the COP at 67°F ambient test conditions only
Correct answer: Using the Uniform Energy Factor (UEF) from the EnergyGuide label
Heat pump water heaters are entered using their Uniform Energy Factor (UEF) as listed on the EnergyGuide label.
Question 6: Which ventilation strategy meets ASHRAE 62.2 requirements by continuously exhausting stale air from bathrooms or kitchens at a calculated whole-house rate?
- Supply-only ventilation
- Balanced ERV ventilation
- Exhaust-only ventilation (Correct answer)
- Spot ventilation only
Correct answer: Exhaust-only ventilation
Exhaust-only ventilation can satisfy ASHRAE 62.2 whole-house ventilation requirements by continuously running a bath or kitchen exhaust fan at the required flow rate.
HERS HERS HVAC Systems and Equipment Evaluation 1
What AFUE rating is the minimum threshold for a gas furnace to be considered high-efficiency under current U.S. energy standards?