Dedicated Outdoor Air Solutions®

When Venmar CES equipment is configured as a DOAS, energy consumption is significantly reduced (in some cases by up to 35% with certain energy efficient parallel systems) by decoupling the heating, cooling and dehumidification loads of the outdoor air from internal sensible heating and cooling loads of the space. Numerous papers have been written and compiled on the advantages of using these systems over traditional VAV designs.

Regardless of the high performance building standard or guideline, the advantages of using a Dedicated Outdoor Air System can significantly contribute to the success of a high performance building project. Dedicated Outdoor Air Solutions optimize energy performance, allow for increased ventilation and better OA modelling. DOAS can contribute to an improved indoor air quality plan during construction and prior to occupancy. In addition, DOAS can contribute to indoor pollutant and source control objectives, as well as provide better (and simpler) ability to meet requirements for thermal comfort.

Dedicated Outdoor Air Solutions also help to meet indoor air quality best practices in existing buildings, and ensure occupant comfort for the life of the building by supporting a well ventilated and well conditioned space which in turn improves satisfaction and productivity.

LEED NC Cheat Sheet
Credit Name
Points Requirement Technology
Benefit
EA Credit 1: Optimize Energy Performance 1–19 Building must beat baseline building (set by 90.1-2007) 12–48%. Detailed energy analysis required to prove energy savings.

DOAS with energy recovery
Geothermal heat pumps
VFDs
FWT

Reduction in energy costs for building owner.
IEQ Credit 2: Increased Ventilation
1
Increase ventilation rate beyond 62.1-2007 by 30%.
DOAS with energy recovery
Ensures additional outdoor air supplied to space for improved indoor air quality for building occupants.
IEQ Credit 3.1 & 3.2: Construction Indoor Air Quality Management Plan
3.1: During Construction
3.2: Before Occupancy
1–2
3.1 – Part of this credit requires the following: Use MERV 8 filters if AHUs are run during construction; replace all filtration prior to occupancy.
3.2 – This credit requires a building flush out and supplying 14,000 cfm/ft2 of outdoor air to help remove VOCs.
DOAS with energy recovery
Improves indoor air quality for building occupancy since construction dust and debris entering the AHUs are minimized.
Improves indoor air quality for building occupancy by minimizing VOCs in the occupied space.
IEQ Credit 5: Indoor Chemical and Pollutant Source Control
1
Part of this credit requires the following: use MERV 13 filtration and replace them regularly.
DOAS with energy recovery
Improves indoor air quality for building occupancy since it minimizes dust and debris from airflow.
IEQ Credit 7: Thermal Comfort
1–2
This credit requires design to ASHRAE Standard 55-2004 and verification of occupant thermal comfort.
DOAS with energy recovery
Building occupants are more likely to be comfortable in a space designed to address thermal conditions; building occupants are more productive in a thermally comfortable facility.


LEED EBOM Cheat Sheet
Credit Name
Points Requirement Technology
Benefit
EA Credit 1: Optimize Energy Efficiency Performance 1–18 Earn Energy Star rating of 71–95 for 1–18 points respectively. Perform better than national average by 21–45% for non-Energy Star eligible buildings. DOAS with energy recovery
Geothermal heat pumps
VFDs
FWT
Reduction in energy costs for building owner.
IEQ Credit 1.1–1.5: Indoor Air Quality Best Management Practices
1.1: Indoor Air Quality Management Program
1.2: Outdoor Air Delivery Monitoring
1.3: Increased Ventilation
1.4: Reduce Particulate in Air Distribution
1.5: IAQ Management for Facility Alterations and Additions
1–5 1.1: This credit requires that an indoor air quality management program be implemented; this will affect HVAC design and operation.
1.2: Use DCV in densely occupied spaces and provide direct outdoor airflow measurement with an accuracy +15%.
1.3: Increase ventilation rate beyond 62.1-2007 by 30%.
1.4: This credit requires the use of MERV 13 filtration and replace them regularly.
1.5: Part of this credit requires the following: use MERV 8 filters if AHUs are run during construction; replace all filtration prior to occupancy.
DOAS with energy recovery 1.1: Ensures delivery of outdoor air and improves indoor air quality for building occupants, reducing risk for building owner.
1.2: Reduced risk to building owner.
1.3: Ensures additional outdoor air supplied to space for improved indoor air quality for building occupants.
1.4: Improves indoor air quality for building occupancy since it minimizes dust and debris from airflow.
1.5: Improves indoor air quality for building occupancy since construction dust and debris entering the AHUs are minimized.
IEQ Credit 2.1: Occupant Comfort–Occupant Survey
IEQ Credit 2.3: Occupant Comfort–Thermal Comfort Monitoring
1–2 Survey of building occupants to determine thermal comfort needs.
Period testing of air temperature and relative humidity in occupied spaces, including testing of airflow and radiant temperature and including alarms for systems that would require repair or adjustment.
DOAS with energy recovery Building occupants are more likely to be comfortable in a space designed to address thermal conditions; building occupants are more productive in a thermally comfortable facility.

External Links

AEE
ASHRAE
DOE

CaGBC
USGBC