ASHRAE WILL GIVE YOU THE WORLD - nccashrae.org · ASHRAE Standard 90.1-2010 2. Select the appropriate unit efficiency for a project and adjust a ... ASHRAE 62.1 1989 ASHRAE 62.1 2010

ASHRAE WILL GIVE

YOU THE WORLD

This ASHRAE Distinguished Lecturer is brought to you by the Society Chapter Technology Transfer Committee

Complete the Distinguished Lecturer

Event Summary Critique

CTTC needs your feedback to continue to improve the DL Program

Distribute the DL Evaluation Form to all attendees

Collect at the end of the meeting

Compile the attendee rating on the Event Summary Critique

Send the completed Event Summary Critique to your CTTC RVC and ASHRAE Headquarters

Forms are available at:

www.ashrae.org/distinguishedlecturers

http://www.ashrae.org/distinguishedlecturers

BECOME A FUTURE LEADER IN ASHRAE – WRITE THE NEXT

CHAPTER IN YOUR CAREER

YOU ARE NEEDED FOR:

Membership Promotion

Research Promotion

Student Activities

Chapter Technology

Transfer Technical

Committees

Find your Place in ASHRAE! Visit www.ashrae.org

ASHRAE Members who attend their monthly chapter meetings become

leaders and bring information and technology back to their job.

http://www.ashrae.org/

Julian R. de Bullet

ASHRAE Distinguished Lecturer

deBullet Consulting

SESSION OBJECTIVES

At the end you should be able to:

1. Explain why a mechanical engineer should understand

ASHRAE Standard 90.1-2010

2. Select the appropriate unit efficiency for a project and adjust a

chiller for non-standard conditions

3. Explain when an economizer must be used

4. Describe when reheat is allowed

5. Use the fan system limitation calculation

6. State when heat recovery must be used

ASHRAE 90.1-2010 BECOMES CODE

As a result of DOE’s ruling, and by the

authority provided through the Energy

Conservation and Production Act, as

amended, states are required to certify

by Oct. 18, 2013 that they have reviewed

the provisions of their commercial build-

ing code regarding energy efficiency and

updated their code to meet or exceed

Standard 90.1-2010. States may request

extensions of this deadline from DOE if

a state can demonstrate that it has made

a good faith effort to comply with this

code update.

STANDARDS AND RATING PROGRAMS

Move to High Performance Buildings

ASHRAE 189.1 2010 LEED® 2012

ASHRAE 90.1 2010

LEED® V3 2009

LEED® V2.2 2005

LEED® V2.0 2000

LEED® V1.0 1998

LEED® V2.1 2002

LEED is a registered trademark of the U.S. Green Building Council.

ASHRAE 90.1 1975

ASHRAE 90.1 1980

ASHRAE 90.1 1989

ASHRAE 90.1 1999

ASHRAE 90.1 2004

ASHRAE 90.1 2007ASHRAE 62.1 2007

ASHRAE 62.1 2004

ASHRAE 62.1 1973

ASHRAE 62.1981

ASHRAE 62.1 1989

ASHRAE 62.1 2010

Used as baseline

Codes in Effect

8

Projected Code Adoption Dates

9

ASHRAE 90.1-2007 ASHRAE 90.1-2010

109 Addenda included, 52 affect HVAC

ESTIMATED SAVINGS 2007 TO 2010

11

1. Scope expanded to cover plug and process loads

(data centers)

2. Building envelope more stringent and high albedo roofs

included

3. Interior Lighting Power Densities lowered,

mandatory daylight controls and exterior lighting zones

4. Expanded equipment efficiencies, new energy

recovery requirements, additional control

requirements

5. Expanded energy modeling requirements (LEED)

MAJOR CHANGES IN 90.1-2010

12

LEED is a registered trademark of the U.S. Green Building Council.

To provide minimum energy efficient requirements of

buildings other than low-rise residential for:

1. Design, construction and a

plan for operation & maintenance

2. Utilization of on-site renewable

energy resources

ASHRAE 90.1 PURPOSE- CHANGES

Applies to:

1. New Buildings and systems

2. New portions of buildings or systems

3. System & equipment additions in

existing buildings

4. Covered portions of

manufacturing facilities

Does not apply to:

1. Single family, residential less than

3-story above grade or modular houses

2. Buildings that do not use

electricity or fossil fuel

ASHRAE 90.1 SCOPE

Where required

• Mandatory

‒ These provisions must be met under all circumstances

and performance can not be traded

Example – HVAC equipment efficiency

• Prescriptive

‒ These provisions are met by using the prescriptive

value or using the performance method

Example – Air side economizer

• Energy Cost Budget (Performance)

‒ Allows trade-offs of prescriptive options if the total cost

is equal to or less than the prescriptive option

PATHS TO COMPLIANCE

• Energy Cost Budget Method

‒ Used to determine trade-off

of performance of one feature

against another feature

• Performance Rating Method

‒ Used to determine the

improvement in performance

of proposed versus baseline

building

ECB VS. PRM

Only part which is code intended

ASHRAE 90.1 – 2010 Regulated Sections

Sect. 5.4 & 5.5 Envelope Requirements

Sect. 6.4 & 6.5 HVAC Equipment

Sect. 7.4 & 7.5 Service Water Heating

Sect. 8.4 Power voltage drop

Sect. 9.4 & 9.5 Lighting control and density

Sect. 10.4 Electric Motors

* See WWW.energycodes.gov/implement/determinations_com.stm

PRIMARY SECTIONS

All of Alaska in Zone 7 except for the following

Boroughs in Zone 8:

Bethel Northwest Artic

Dellingham Southeast Fairbanks

Fairbanks N. Star Wade Hampton

Nome Yukon-Koyukuk

North Slope

Zone 1 Includes

Hawaii, Guam,

Puerto Rico,

and the Virgin Islands

Dry Moist (A)Marine (C)

CLIMATE ZONES

Zone 1

2. ASHRAE 90.1 has requirements that do not regulate the

energy use of which of the following?

a) Lighting power density

b) Plug power from computers

c) Task lighting

d) Minimum insulation values for roof

e) Power limit for pumps on an ornamental water garden

f) Maximum amount of ventilation air that can be provided

g) Data centers

h) Plug loads

EXERCISE

SECTION 6 – HVAC

6.7 Submittals

Section 6 Heating, Ventilation and Air Conditioning

6.1 General

6.3 Simplified Approach

6.5 Prescriptive PathSection 11 Energy Cost

Budget Method

6.4 Mandatory Provisions

6.2 Definition of Compliance Paths

1. Process applications added (data centers)

2. Updated efficiency tables and added equipment types

3. Liquid – to – liquid heat exchangers now covered under AHRI 400

4. Restrictions on pump head and pipe sizing

5. VAV requirement for CW and DX single zone units

6. Significant increase in insulation for ducts and pipe

7. Added radiant panel system requirements

8. Changes to airside economizer requirements

9. Changes to damper leakage requirements

10. Changes to reheat / recool minimum use and application

11. Requirement for dynamic ventilation control on VAV requirement from Std 62.1

12. Limit on use of centrifugal fan open towers

13. A climatic based requirement for energy recovery

14. New requirements for garage and kitchen ventilation

15. New requirements for laboratory exhaust

MAJOR CHANGES TO HVAC

1. Building is two stories or less

2. Gross floor area is ≤ 25,000 ft2

3. HVAC system serves one zone

4. Must have single zone VAV capability

5. Cooling system is unitary packaged or split system that meet

the required efficiencies

6. Economizer must be used if required by climate zone

7. Heating must be by heat pump or furnace that meets the

required efficiencies

8. Energy recovery if zone and outdoor air requirement are met

9. Must use a manual changeover thermostat

10. Heat pump lockout of supplementary heater required

SIMPLIFIED APPROACH

Star indicates an important change

11. Reheat and simultaneous heating and cooling is prohibited

even for humidity control

12. Units with motors greater than ¾ hp must have a time clock

with 2-hr override, and provide setback to 55⁰F and set-up to

90⁰F

13. Pipes must be insulated per requirements

14. Duct must be sealed and insulated per requirements

15. Air balance required

16. Multiple units to a space must be interlocked

17. Exhaust in a system over 300 CFM must be equipped with

gravity or motorized damper

18. Systems over 10,000 CFM must have optimum start control

SIMPLIFIED APPROACH (CONTINUED)

3. Which of the following is not a case covered by the scope

of ASHRAE 90.1 2010?

Choose one answer.

a) The area of a building being renovated if it is more that 50%

b) Refrigerant change - out with existing equipment that does

not comply

c) A new building that is heated but not cooled

d) A high rise apartment building where the tenant furnishes

their own AC unit

EXERCISE

Tables6.8.1A – Air Conditioners and Condensing Units

6.8.1B – Heat Pumps

6.8.1C – Water – Chilling Packages

6.8.1D – Packaged Terminal and Room Air Conditioners

6.8.1E – Furnaces, Duct Furnaces, and Unit Heaters

6.8.1F – Boilers

6.8.1G – Heat Rejection Equipment

6.8.1H – Heat Transfer Equipment

6.8.1I – VRF Air Conditioners

6.8.1J – VRF Air-to-Air & Applied Heat Pumps

6.8.1K – Computer Room Units

EQUIPMENT EFFICIENCIES

Air-Cooled Packaged

EQUIPMENT EFFICIENCIES-ALL CHANGED

30% Increase

17% Increase

Note: Both requirements must be met

Water-Cooled Packaged

EQUIPMENT EFFICIENCIES-CHANGES

IMPACT OF ASHRAE 90.1 – 2010-CHANGES

28

Air Conditioner ASHRAE 90.1 -- 2004

Air Conditioner ASHRAE 90.1 -- 2010

Example Unit

EQUIPMENT EFFICIENCIES

CHILLER EFFICIENCIES- CHANGES

tonkWCOP

/

516.3

Conditions:

44F LWT

85F ECWT

3 GPM/ton

Path A –

Normal duty

Path B –

Continuous duty

Assume we have a 750 ton centrifugal chiller that meets

path A requirements

Full load kW/Ton = 0.570 , IPLV = 0.539

Lvg Cond = 91.16 F

Lvg Evap = 42 F

Lift = 91.16 – 42 = 49.16 F

A = 0.0000014592 x (49.16)4 – 0.0000346496 x (49.16)3 +

0.00314196 x (49.16)2 -0.147199 x (49.16) +3.9302

A = 1.0228

B = 0.0015 x 42+ 0.934 = 0.9970

Adj Full Load kW/Ton = 0.570/(1.0228 x 0.9970) = 0.559

NPLV = 0.539 /(1.0228 x 0.9970) = 0.529

EXAMPLE CHILLER AT NON-STANDARD

1. When evaluating if a chiller with lower efficiency

can be substituted for the mandatory requirement of

ASHRAE 90.1 – 2010 for chiller efficiency which

method should be used?

Choose one answer.

a) The Appendix G Performance Rating Method

b) The Section 11 Energy Cost Budget Method

c) The prescriptive requirement from Section 6.4

d) None, since it is a mandatory requirement

EXERCISE

6.4.2.1 Load Calculations

Heating and cooling loads must be calculated

per ANSI / ASHRAE / ACCA Standard 183-2007

Peak Heating and Cooling Calculations in

Buildings Except Low-Rise Residential

6.4.2.2 Pump Head

Pump head must be calculated by the

pressure drop in the critical circuit at design

REQUIRED CALCULATIONS

Ventilation Controls

6.4.3.4.1Stair shafts and elevators must have motorized shut-off

dampers

6.4.3.4.2

1) Outdoor air and exhaust must have automatic

dampers with ability to shutoff during warm-up,

cool-down and unoccupied times

‒ Gravity dampers allowed

• For exhaust and relief if building is ≤ 3 story

• For Intakes in Zones 1,2,3

• System is less than 300 CFM

6.4 MANDATORY REQUIREMENTS


3) Damper leak rate:

Ventilation Exhaust / Relief

Gravity Motorized Gravity Motorized

Zone 4,5b,5c

< 3 Story Not allowed 10% 20% 10%

≥ 3 Story Not allowed 10% Not Allowed 10%

Zone 5a,6,7,8

< 3 Story Not allowed 4% 20% 4%

≥ 3 Story Not allowed 4% Not Allowed 4%



6.4.3.4.4

Ventilation fans greater than ¾ hp must have

automatic shutdown capability when not required

6.4.3.4.5

Enclosed parking garages shall be able to modulate

to 50% or less of design airflow if contaminate levels

are maintained


6.4.3.5:Heat Pump Auxiliary Heat Control

Supplemental heater must have controls that

prevent operation when the heat pump is capable

of meeting the load during operation and recovery-

heater operation is permitted during defrost

6.4.3.7:Humidification and Dehumidification

System must be able to prevent humidification from

working when dehumidification is active

6.4.3.8:Freeze Protection and Snow Melting Systems

Must be deactivated above 40⁰F


6.4.3.9:Ventilation Controls for High Occupancy

High occupancy is > 40 people/1000 ft2

For spaces > than 500 ft2 require DCV if system has:

Airside economizer

Automatic modulating control of outdoor air damper

Airflow > 3000 CFM

Unless:

System exhaust energy recovery (6.5.6.1)

System does not have a DDC system

System outdoor airflow is ≤1,200 CFM


6.4.3.10

1. CW AHU or fan coil with motor >5 hp must

have either 2–speed motor or VFD to reduce

airflow at 50% demand or less to either

a) ½ of full speed

b) Airflow required for ventilation per Std 62.1

2. As of 1/1/2012 DX units 110,000 Btuh or more

must have either 2–speed motor or VFD to

reduce airflow at 50% demand or less to

1) ⅔ of full speed

2) Airflow required for ventilation per Std 62.1

SINGLE ZONE VAV CONTROLS

1. All duct above 2” wg. and

upstream of VAV boxes

must be sealed to class A

2. Pressure testing of minimum

of 25% of duct area required

on duct systems over 3” wg.

DUCT SEALING

1. Select 3 mandatory requirements of ASHRAE 90.1 2010

related to HVAC units?

Pick at least three answers.

a) HVAC equipment part load efficiency

b) 20 degree differential in WSHP loop boiler off to cooling tower

on temperature

c) Pumps with over 50 HP must have a VFD

d) Reheat limited to less than 0.4 CFM / ft2

e) Motorized damper leakage at no more than 10 CFM / ft2

f) Optimum start control for systems over 10,000 CFM

g) Dead band of at least 5 F between heating and cooling setpoint

EXERCISE 4

Comfort Cooling (air or water) All zones except 1a and 1b ≥ 54,000 Btu/h

Computer Rooms

Zones 1a, 1b, 2a, 3a, 4a - Not required

Zones 2b, 5a, 6a, 7, 8 ≥ 135,000 Btu/h

Zones 3b, 3c, 4b, 5b, 5c 6b ≥ 65,000 Btu/h

Exceptions:

‒ Non-particulate air treatment required by Std 62.1

‒ Hospitals with >75% space requiring humidification above 35 F dewpoint

‒ Condenser heat recovery is used

‒ Residential spaces

‒ If internal sensible cooling at design is less that transmission at 60F

‒ System operation less that 20 hr / week

‒ Supermarkets when it will impact case

‒ If unit efficiency exceeds 42% better in 4a and 49% better in zone 5a

‒ Computer rooms in some conditions

6.5.1.ECONOMIZER REQUIREMENTS

6.5.1.1 PRESCRIPTIVE REQUIREMENTS

EconomizersAir Economizer

‒ Modulate outdoor air and return air to provide 100%

of supply air quantity – must provide relief

‒ Must be integrated with cooling and can not be controlled

only by mixed air temperature

‒ Relief that prevents recirculation must be provided

High limit cut-off Control

Zone 4a Zone 5a

Fixed Dry Bulb Not Allowed TOA > 70

Differential Dry Bulb Not Allowed TOA > TRA

Fixed Enthalpy hOA > 28 Btu/lb

Electronic Enthalpy (TOA ,RHOA)> A

Differential Enthalpy hOA > hRA

Dew-point and dry-bulb DPOA >55F or TOA > 75F

6.5.1.2 PRESCRIPTIVE REQUIREMENTS

EconomizersWater Economizer

‒ Provide 100% of capacity by indirect evaporative cooling at50⁰F DB and 45⁰F WB

‒ Pressure drop can not exceed 15 ft on primary or use a

secondary loop

‒ Must use integrated economizer

Except:

‒ Some computer room applications

‒ System where dehumidification requirements can not be metat 50⁰F DB and 40⁰F WB

6.5.1.4: All Economizer

Economizer operation can not increase the need for heating

energy at normal conditions

5. A chiller using glycol solution with a freezing point less than 27⁰ F should use which efficiency rating condition?

Select one answer

a) Full load kW / ton

b) Full load COP

c) Part load IPLV

d) None ‒ These are outside the range

e) EER rating

f) IEER rating

EXERCISE 5

6.5.2 PRESCRIPTIVE REQUIREMENTS

Simultaneous Heating and Cooling Limits

Zone controls must prevent:

Reheating

Re-cooling

Mixing of air that has been mechanically heated

or cooled by mechanical cooling or economizer

Other simultaneous operation of heating and cooling


Condition 1

Exceptions where reheat is allowed if the air reheated

is less than the larger of the following:

1. Air is no less than the required

zone ventilation air per Standard 62.1

2. Air is < 30% of peak design airflow

3. If allowed by AHJ when shown that it reduces

total energy

4. Zones requiring pressure differential or

code requirement

AHJ: Authority having jurisdiction



Condition 2

Exceptions where reheat is allowed if the zone meets

all the following:

1. Airflow rate in the dead band between heating and cooling

is not larger than:

1. 20% of the zone peak airflow

2. Required zone ventilation air per Standard 62.1

3. If allowed by AHJ when shown that it reduces total energy

2. Reheat, recooled or mixed air is less than 50% of peak

3. Airflow between dead band and full heating and full cooling

can be modulated

6.5 PRESCRIPTIVE REQUIREMENTS


Condition 3

Exceptions where reheat is allowed if:

1. Laboratory exhaust that meets Section 6.5.7.2

Condition 4

Exceptions where reheat is allowed if:

1. 75% of the reheat energy is

from site recovered energy

or site-solar assisted energy


6. New energy for reheat is allowed in which 3 of the

following situations?

Select three answers.

a) The airflow has been reduced to the minimum

ventilation air allowed by ASHRAE 62.1

b) Minimum air volume is < than 0.4 CFM/FT2

c) Reheat is only allowed if no new energy is used

d) Reheat is never allowed except in process applications

e) Air being reheated is < 30% of peak design airflow

EXERCISE

Air System Design and Control

Systems over 5 hp total system nameplate must meet the fan hp

limitation based on name plate hp

Fan Power limitation

Supply fans, return fans, relief fans, exhaust fans and fan-powered

terminal units must meet option 1 or option 2

Exceptions:

‒ Hospital and labs where pressure differential must be maintained

can use VAV fan power limit

‒ Individual exhaust fans with motor name plate of 1 hp or less

Motor nameplate can be no larger than the next available motor size

Exceptions:

If bhp is < 6 – motor can be within 50% of bhp

If bhp is ≥ 6 – motor can be within 30% of bhp


Option 1 ‒ VAV system supplying 25,000 CFM

hp limit = CFMs x 0.0015 = 25,000 x 0.0015 = 37.5 hp

Maximum is then 37.5 Nameplate hp

AHU systems with 30 hp supply and 7.5 hp exhaust

nameplate motors would be acceptable

Option 2 – Same systems full ducted and MERV 13 filters

hp limit = CFM s x 0.0013 + A

A = Pd x CFM / 4131

A duct = 0.5 x 22,000/4131 = 2.66

A MERV 13 = 0.9 x 25,000/4131 = 5.44

hp limit = 25,000 x 0.0013 +2.66 +5.44 = 40.6 bhp

Maximum is then 40.6 bhp

FAN POWER EXAMPLE

52

(Includes series fan power boxes)

‒ All motors 10 hp and larger must:

1. Be driven by a mechanical or electrical variable speed drive

2. Or use a vane-axial or variable pitch fan

3. Or have controls that will reduce motor demand to

30% of design watts at 50% flow

‒ Static pressure sensor must be placed so that the

controller setpoint is no more than 1/3 of total design static

‒ On DDC systems static setpoint must be reset by the

zone with the largest demand

6.5.3.2 VAV FAN POWER LIMITS

53

Multiple zone systems must (6.5.3.3):

• Provide reset control of supply air in response to load

or outdoor air temperature

‒ Must be capable of resetting 25% of the

difference between supply air and room setpoint

‒ Reset based on humidity is allowed

‒ Equipment rooms (data centers) must be able to fully reset

Except:

‒ Zones 1a, 2a and 3a

‒ Systems that prevent reheating, re-cooling or mixing

‒ Systems with 75% reheat energy from site recovered

or site solar

SUPPLY AIR TEMPERATURE RESET

54

7. ASHRAE 90.1 has a prescriptive requirement which limits

the fan power energy. Which of these statements is true?

Select one answer

a) The calculation only applies to the power at part load

conditions of VAV units using a variable frequency drive

b) A correction factor is applied when filters with a MERV

rating greater than MERV 8 are used

c) The calculation of fan power applies to supply, return,

and exhaust fans but not the fans in VAV fan powered

terminals.

d) The power calculation must be based on the nameplate

rating of the motor only

EXERCISE

Hydronic System Control

‒ Systems with pumps 10 hp and larger and control valves must be

capable of reduction to 50% design flow

‒ Pumps over 5 hp must have the ability to reduce to

30% power at 50% flow

‒ Controls shall function to maintain minimal pressure differential

and drive the valve with the greatest demand full open

‒ Differential pressure should be no more that required for

110% of heat exchanger flow

Exceptions:

‒ Flow less than manufactures minimum where pump hp is

75 hp or less

‒ System has no more than 3 control valves


Hydronic System Control

‒ Pumps on systems with more than one chiller must have

isolation of the used chiller (6.5.4.2)

‒ Chilled and hot water in systems > 30,000 Btu/h must reset

chilled and hot water temperature based return water

temperature or outdoor temperature (6.5.4.3)

Except:

‒ When control reset will cause improper operation

of heating, cooling, humidifying or dehumidification

‒ Hydronic systems using variable flow pumping

‒ Hydronic loops must use two-position isolation valves to stop

water flow when the compressor is off applies to WSHP and

unitary water cooled units



Energy Recovery

Exhaust air energy recovery is required if:

Exhaust Air Heat

Recovery

8. Heat recovery is required by ASHRAE 9.1 2010 under

certain conditions. Which requirements are true?

Select one answer.

a) In zone 5a the airflow is 5500 CFM and 30% is outside air

b) The energy effectiveness is less than 50%

c) An economizer is not required if an ERV with a thermal

effectiveness of 50% or better is used

d) Energy recovery is required if 75% of the lab hood are not

controlled by a demand control ventilation or schedule

EXERCISE

Hot Gas Bypass Limitation

Cooling systems can not use

hot gas bypass or evaporator pressure

control unless multiple steps of capacity

are provided and maximum hot gas

is limited to:

≤ 240,000 Btu/h 50% maximum

> 240,000 Btu/h 25% maximum

Exception:

Unitary systems less than 90,000 Btu/h

This includes screw and centrifugal machines and is based on the

system size IE: 100 ton machine can not bypass more than 25 tons


• One or more pressure sensors shall be used to vary the

pump speed and/or start and stop the pumps.

• No device shall be installed for the purpose of reducing

the pressure of all of the water supplied by any booster

system pump or booster system, except for safety

devices.

• No booster system pumps shall operate when there is no

service water flow

Conclusion

Every booster pump system will be variable flow

10.4.2 Service Water Booster Systems

61

Performance Rating MethodDemonstrate a percentage improvement above the baseline building

Note:

Based on energy costs

Must meet 90.1 mandatory requirements

Must include all project energy costs

Baseline building must comply with

Appendix G requirements

Process energy requirements

Appendix G is for modeling improvedperformance not tradeoff calculations

ASHRAE 90.1 NORMATIVE APPENDIX G

THANK YOU!

63

Documents

ASHRAE WILL GIVE YOU THE WORLD - nccashrae.org · ASHRAE Standard 90.1-2010 2. Select the appropriate unit efficiency for a project and adjust a ... ASHRAE 62.1 1989 ASHRAE 62.1 2010