Air Control Considerations For Energy Conservation & BMS Integration

Presenter: James Livingston,

Ruskin Company

� Control Damper Basics

� Control Damper Leakage

� Control Damper Design For Energy

Conservation

� Fire/Smoke Damper Acutators For

Energy Conservation

We Will Discuss

What is a Control Damper?

One or more movable blades

Mounts in ducts or openings

Regulates the flow of air

Control Damper Applications

� Air Handling Units (AHU)

� Mixing Boxes

� Fresh Air (FA)

� Return Air (RA)

� Backdraft Dampers (BD)

� Zone Mixing Dampers (ZMD)

Parts of a Control Damper

Frame

Blade

Linkage

Jamb Seals

Blade Seals

Galvanized

V-Groove Blades

Airfoil Blades

Aluminum

Frames

Damper Construction

V-Groove Blade Dampers

• Velocities less than 1500 FPM

• 3”- 4” Static Pressure

• Noise not a factor

Airfoil Blade Dampers

• Velocities above 2000 FPM

• Above 3”- 4” Static Pressure

• Noise is a concern

• Lowest Pressure Drop Required

How Are Fire, Fire/Smoke and Smoke Dampers Different?

� Maintains fire or

smoke walls

� Fire dampers - steel

construction

� Often have sleeves

� Usually not controlling

air

� That is changing!

Damper Leakage – What is it?

Per AMCA Publication 502, Damper

Application Manual for Heating,

Ventilating and Air Conditioning:

“The Air Leakage, or Sealing

Performance, of a closed damper is

the airflow leakage rate through the

damper for a given pressure

differential across the damper.”

Leakage

Why Are We Concerned?

� Code requirements

� Energy losses due to

escaping conditioned air through closed damper

� Maintaining pressure in system with closed

damper

Control Damper Leakage Classes

Smoke & Fire/Smoke Damper Leakage Classes

Damper Leakage Notes

� Leakage is a function of Pressure, not Airflow

� Generally expressed or plotted as:

� Cfm/ft² of damper face area at a certain pressure

and with a certain seating torque

� Metric: m³/second per m²

� Example for a 24” x 24” opposed blade

damper:

� 32 cfm/ft² @ 4” w.g. pressure with 5 inch-pounds/ft² torque applied holding damper closed

Calculating Leakage

� Most dampers have published leakage at 1”

w.g.

� Multiply the cfm leakage at 1” times the

square root of the desired pressure

� Example

� 10 cfm @ 1” w.g. = 20 cfm @ 4” w.g.

� Be sure the damper is rated for the higher pressure!

17

International codes have been adopted in International codes have been adopted in

All 50 states, D.C. & Puerto RicoAll 50 states, D.C. & Puerto Rico

One or more International Codes currently enforced statewide

www.iccsafe.org

International CodesInternational Codes

International CodesInternational CodesInternational codes mandate…

� Occupancy-based ventilation (IMC 403.3)

� VAV systems shall have controls to monitor and maintain O.A. flow based on 403 requirements, through the entire range of the system (IMC403.3.3)

� All dampers penetrating the building envelope shall be class 1 leakage rated, not to exceed 4cfm/sf @ 1”w.c. (IMC301.2, IBC1301 & IECC)

� Motorized dampers required on building envelope penetrations (IECC 502.4.4 & 503.2.4.4)

D.O.E. mandates ASHRAE 90.1 as a minimum for all

Federal buildings. (IECC 4 CFM Supersedes)

“The occupant load utilized for design of the

ventilation system shall not be less than the

number determined from the estimated maximum

occupant load rate indicated in Table 403.3”

International CodesInternational Codes

International Mechanical CodeInternational Mechanical Code

Regard

ing Ene

rgy

Conser

vation

International Mechanical CodeInternational Mechanical Code

Regard

ing Ene

rgy

Conser

vation

International Building CodeInternational Building Code

International Energy Conservation CodeInternational Energy Conservation Code

• Required in all states that have

adopted the IBC or IMC.

• Addresses OA & EA Damper

leakage

4 cfm/ft2@ 1” w.g.

• Economizers Required (503.3.1 &

503.4.1)

• Refers to 90.1 for climate zones

and as a standard for

applications not covered in the

code.

International Energy Conservation CodeInternational Energy Conservation Code

ASHRAE 90.1

6.4.3.3.3 Motorized dampers

required on OA & EA applications

6.5.1.1 Economizers required

Specifying Low Leakage Dampers

� AMCA 511 Certification

� Independent testing

� Verified catalogs

� Periodic Check Tests

27

Certified Ratings Program…

How do you know the product you specified is licensed by AMCA International?

There are basically four ways to determine if a product is participating in AMCA International’s Certified Ratings Program. They are:

� WWW.AMCA.org

� Manufacture

� Model #

� Manufacture’s Catalog (most are online)

� Certified Ratings Seal on the product (could be too late)

� Contact AMCA International

� Phone 847-394-0150

� Fax 847-253-0088

� Email crp@amca.org

AMCA International

AMCA 511 Damper Air Leakage

� At least two sizes tested

� 12” x 48”

� Max width x 36”

� Up to two more sizes can be tested, 36” max tall

� AMCA configs 5.4, 5.5 or 5.6

� Round dampers

� Min & Max sizes tested

� AMCA 500 Test Standard

Figure 5.5

Leakage &

Pressure

AMCA 511 Damper Air Leakage

Damper Leakage Chart

Damper Leakage Performance

Air Leakage Certification

Not the same!

Be sure it’s rated for Air Leakage, not just Air Performance!

Energy Saving Damper Construction

Blades

Jamb Seals

Blade Seals

Galvanized

V-Groove Blades

Airfoil Blades

Aluminum

Blades

Generally not Class 1

Class 1 and 1A available

Airfoil Blades

� Advantages

� Best Torsion Performance

� No Twist

� Best Closure Seal For

All Blade Lengths

� Class 1 & 1A available

� Blade Shape Matters

� Airfoil

� 60” Span @ 3.5 w.g.

� 3000 FPM

� 3-VEE

� 48’ Span @ 2.5 w.g.

� 1500 FPM

Airfoil vs. “V” Groove Maximums

24” x 24”

Airfoil

.07 w.g. @ 2000 FPM

3-VEE

.19 w.g. @ 2000 FPM

Almost 3 times the Pressure Drop!

Airfoil vs. “V” Groove Pressure Drop

Jamb Seals

� Between ends of

blades and jamb

frames

� Metallic or synthetic

material

� Compresses when

blades close

Blade Seals

� Blade Seals

� Mechanically Locked

� Inflatable

� Wiper Type

No Adhesive or Clip On Style

Maintenance

Insulated Dampers� Reduces thermal energy loss

� Different methods

� Double airfoil damper -

expensive

� Single airfoil foam injected

blades – less expensive

� Thermal break frames available

� Class 1 leakage

� Applications down to -100°F

41

Louver & Damper in One!

Combination Louvers� Drainable fixed louver & airfoil

control damper in same frame

� Class 1 leakage

� Meets IECC building envelope

leakage requirement!

� Available w/ most electric

actuators

� Less product cost than separate

louver, damper & sleeve

� Less installation cost

Damper Electric Actuators

Electric Actuator Types

� Actuators are available in three types:

1) Two Position Spring Return

2) Modulating

3) Power Open-Power Closed

� Can be controlled by BMS

� Most Damper applications call for

Two Position Spring Return or Modulating

Two Position

� Limit to limit operation – does not float

� Open/close applications

� Spring reverses direction when power fails

� Typically 120V or 24V voltage

� Power draw for common 175 in/lb model� 120V – 60 VA driving, 13 VA holding

� 24V – 40 VA driving, 8 VA holding

Modulating� Actuator moves too any point within

its rotation limits to control airflow

� Requires a control signal� 2-10 Vdc or 4-20 mA

� Signal can come from BMS based on:� Temperature

� Pressure

� Air pollutants and/or occupancy

� Power draw for common 175 in/lb model� 24V – 16 VA driving, 5 VA holding

Actuator Installation Options

Modulating Considerations

� Airflow not linear to blade position

Modulating Considerations

Linear flow damper characteristics

From AMCA Pub 502 Damper Application Manual

Modulating Fire/Smoke and Smoke Damper Actuators

� BMS signal controls

blade position in normal

condition

� Damper closes fully

during fire

� Damper opens fully to

relieve smoke

Modulating Smoke & F/S Dampers

� Eliminates balancing

dampers

� Less pressure drop

� Less cost

� Use smoke dampers for

return air on Air Handlers

� Maintain floor pressure in

multi floor systems

Modulating Smoke & F/S Dampers

Modulating Smoke & F/S Dampers

� Advantage over

manual balancing

dampers

� Modulating actuator goes full-open for

smoke purge

� Smoke system does not have to fight semi-

closed manual dampers

Built in potentiometer to Built in potentiometer to

20% to 100% balance 20% to 100% balance

positionposition

Allows the damper to be SET at Allows the damper to be SET at Allows the damper to be SET at Allows the damper to be SET at Allows the damper to be SET at Allows the damper to be SET at Allows the damper to be SET at Allows the damper to be SET at

any position for BALANCING any position for BALANCING any position for BALANCING any position for BALANCING any position for BALANCING any position for BALANCING any position for BALANCING any position for BALANCING

AIRFLOW under normal AIRFLOW under normal AIRFLOW under normal AIRFLOW under normal AIRFLOW under normal AIRFLOW under normal AIRFLOW under normal AIRFLOW under normal

operations, open or closed for operations, open or closed for operations, open or closed for operations, open or closed for operations, open or closed for operations, open or closed for operations, open or closed for operations, open or closed for

SMOKE CONTROL and closed as SMOKE CONTROL and closed as SMOKE CONTROL and closed as SMOKE CONTROL and closed as SMOKE CONTROL and closed as SMOKE CONTROL and closed as SMOKE CONTROL and closed as SMOKE CONTROL and closed as

required in the fire arearequired in the fire arearequired in the fire arearequired in the fire arearequired in the fire arearequired in the fire arearequired in the fire arearequired in the fire area

No Control No Control No Control No Control

Signal Signal Signal Signal

RequiredRequiredRequiredRequired

3-Position Smoke & F/S Dampers

Summary

� Current building codes require low leakage

dampers

� Damper construction greatly affects leakage

characteristics

� Modulating actuators can be controlled by

BMS to adjust airflow for temperature and

IAQ requirements

� Smoke and Fire/Smoke dampers are

available w/ modulating & 3-position

actuators

Questions?

Thank You!