ESET 444 EXAM QUESTIONS AND
ANSWERS GRADED A+ 2025/2026
This system keeps supply air always at the same temperature, and delivers more or less air as
required to maintain or change the temperature in the space - ANS Variable Air Volume
This system always delivers the same airflow but the air may be hotter or colder as required to
maintain or change the temperature in the space - ANS Constant Volume
How can a single-duct system be divided into zones with different thermal requirements? -
ANS Either reheat method or VAV method could be used
An air-side economizer is used when: - ANS The enthalpy of outdoor air is lower than that of
the return air. The outdoor air is then used to provide free cooling, by bringing in more outdoor
air than is required to meet needs for fresh air ventilation.
Reheat systems have many advantages - they permit simple zone control for areas with different
loads, can provide heating or cooling to different areas at the same time, maintains close
control over humidity and offers flexibility when zones are selected at design stage. What is the
main disadvantage? - ANS The system uses energy to cool air and then uses energy again to
heat it back up. This is wasteful of energy and uneconomical
Which of the following is/are disadvantages of a zoned variable air volume system? -
ANS Possibly poor ventilation if a zone does not require much air for cooling
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
ANSWERS GRADED A+ 2025/2026
This system keeps supply air always at the same temperature, and delivers more or less air as
required to maintain or change the temperature in the space - ANS Variable Air Volume
This system always delivers the same airflow but the air may be hotter or colder as required to
maintain or change the temperature in the space - ANS Constant Volume
How can a single-duct system be divided into zones with different thermal requirements? -
ANS Either reheat method or VAV method could be used
An air-side economizer is used when: - ANS The enthalpy of outdoor air is lower than that of
the return air. The outdoor air is then used to provide free cooling, by bringing in more outdoor
air than is required to meet needs for fresh air ventilation.
Reheat systems have many advantages - they permit simple zone control for areas with different
loads, can provide heating or cooling to different areas at the same time, maintains close
control over humidity and offers flexibility when zones are selected at design stage. What is the
main disadvantage? - ANS The system uses energy to cool air and then uses energy again to
heat it back up. This is wasteful of energy and uneconomical
Which of the following is/are disadvantages of a zoned variable air volume system? -
ANS Possibly poor ventilation if a zone does not require much air for cooling
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
