[L8]_System Loads Flashcards
IND405
What is the difference between space and system loads?
[L8]
Space load calculated include the necessary values to satify the envelope load, but does not account for other heat gains/losses that occur from equipment outside of the envelope.
[L8]
IND405
(Yes or No) It is possible to have a scenario where HVAC equipment heat gain loads can be larger than the combined space loads of a project?
[L8]
Yes.
[L8]
IND405
List the four (4) common System Loads outside of Space Loads.
[L8]
- Infiltration/Ventilation Load
- AHU Fan Load
- Ductwork Load
- Plenum Load
[L8]
IND405
What is the most common type of ventilation for existing building projects?
* Natural Ventilation
* Mechanical Ventilation
[L8]
Natural Ventilation
[L8]
IND405
What is the type of engineering design process is required to complete a project correctly?
[L8]
An iterative engineering design approach is required to meet the goals of the client.
[L8]
IND405
What is the difference between Block & Peak building loads?
[L8]
Peak loads mean that the size of the system is based on the total peak CFMs in each room, while block loads mean that the size of the system is based on when the building as a whole is busy.
[L8]
IND405
To obtain the maximum amount of comfort in a space which is better? Single-Zone T-Stat or Multi-Zone T-Stat
[L8]
Multi-Zone T-Stat
[L8]
IND405
What is the largest heat gain or loss in terms of system loads?
a) Miscellaneous heat gain
b) Ductwork heat gain
c) Outdoor air introduced in mechanical ventilation
[L8]
Outdoor air introduced in mechanical ventilation
[L8]
IND405
Which equation is used to calculate an HVAC System Total Cooling Load?
a) Q = (1.1 x CFM SA) x (ΔT)
b) Q = (4840 x CFM SA) x (Δw)
c) Q = (4.5 x CFM SA) x (Δh)
[L8]
Q = (4.5 x CFM SA) x (Δh)
[L8]
IND405
Which equation is used to calculate HVAC System Total Heating Load?
a) Q = (4.5 x CFM SA) x (Δh)
b) Q = (1.08 x CFM SA) x (ΔT)
c) Q = (4840 x CFM SA) x (Δw)
[L8]
Q = (1.08 x CFM SA) x (ΔT)
[L8]
IND405
What is the purpose of a psychrometric chart?
[L8]
To determine the properties of air, such as temperature, humidity, and enthalpy in order to calculate HVAC system loads at specific outdoor and indoor design temperatures.
[L8]
IND405
What is enthalpy?
[L8]
The total energy content of air.
[L8]
IND405
What is an economizer cycle?
[L8]
A cycle that uses outdoor air to cool a space instead of mechanical refrigeration.
[L8]
IND405
What is an air handling unit (AHU)?
[L8]
A fan system used to filter and circulate air in HVAC systems.
[L8]
IND405
What is an Energy Recovery Ventilator (ERV)?
[L8]
A fan system with a fixed heat exchanger core or enthalpy wheel used to recover waste energy from indoor HVAC conditions and to preheat or precool required outdoor fresh air.
[L8]
IND405
What is an Evaporative Cooler?
[L8]
A type of cooling system that uses outdoor air and water evaporation to cool a space.
[L8]
IND405
What is an Absorption Chiller?
[L8]
Absorption Chillersuse heat energy inputsto coolair. It employs two refrigerantcoolants. The first one evaporates and the second one absorbs it. Heat restores the two coolants.
[L8]
IND405
What is the purpose of a VAV system?
[L8]
To vary the air flow in a space based on current real time demand.
[L8]
IND405
What is the difference between constant volume and variable volume systems?
[L8]
Constant volume systems maintain a constant air flow, while variable volume systems vary the air flow based on demand to satisfy the current # of people and design temperature.
[L8]
IND405
What is a Building Automation System (BAS)?
[L8]
A system that controls and monitors various the entire building functions, including HVAC, lighting, and security.
[L8]
IND405
What is Commissioning?
[L8]
The process of verifying that an HVAC system is installed and operating correctly according to design specifications.
[L8]
IND405
What is Retrocommissioning?
[L8]
The process of commissioning an existing HVAC system that was not previously commissioned and its sequence of operation is correct now.
[L8]
IND405
What is an Air-Barrier?
[L8]
A material or system that prevents the movement of air through the building envelope.
[L8]
IND405
What is an Insulation Barrier?
[L8]
A material or system that reduces heat transfer through the building envelope.
[L8]
IND405
What is thermal bridging?
[L8]
The transfer of heat through materials that are poor insulators, such as metal studs or concrete slabs.
[L8]
IND405
In a window, do you usually want or not a thermal break?
[L8]
Yes, you want to include a thermal break to stop heat transfer through the window frame.
[L8]
IND405
How can thermal bridging impact energy efficiency in a building?
[L8]
Thermal bridging can reduce energy efficiency in a building by allowing heat to transfer through materials that are poor insulators, such as metal studs or concrete slabs, which can increase heating and cooling loads on the HVAC system.
[L8]
IND405
What is the purpose of an Energy Audit?
[L8]
The purpose of an energy audit is to identify opportunities for improving energy efficiency in a building, including HVAC systems, lighting, and building envelope.
[L8]
IND405
How can HVAC systems impact the acoustics of a building?
[L8]
HVAC systems generate noise that can travel via ducts or radiate from equipment, affecting building acoustics. HVAC system design and installation may reduce noise and increase comfort.
[L8]
IND405
What is the role of thermal storage in HVAC systems?
[L8]
Thermal storage lets HVAC systems move cooling or heating loads to times when energy costs are lower. This cuts down on energy use and charges for high demand.
[L8]
