Economizer Training

XX/XX/XX HONEYWELL - CONFIDENTIAL File Number

An Arrangement of….

Dampers

Actuators

Controls

...that allow the use of OUTDOOR AIR to achieve FREE COOLING without the use of mechanical stages.

What is an Economizer?


Components in an Economizer System

•Logic Module - The “Brains” of the system, makes the decisions based

on input from sensors

•Sensors Determine the conditions and give feedback to the logic

module

•Actuator The dumb workhorse, changes damper position based on

a signal from the logic module


Typical Economizer

OA Sensor

OA Dampers

RA Damper

Mixed Air

Sensor

RA Sensor (optional)

Fresh Air Intake

Actuator and Logic


Why Have an Economizer?

IT SAVES MONEY IMMEDIATELY

Reduce Compressor Run Time and energy usage

Prevents Excessive Outdoor Air During Heating Season

IT SAVES MONEY LONG TERM

Reduced Equipment Maintenance and Service Costs

Extends Equipment Life and Eliminates Premature Replacement Costs

THE “COMFORT FACTOR”

To Provide Fresh Air to Building Occupants

To Meet “Indoor Air Quality” Standards

Why Use an Economizer?


How Does an Economizer Work?

Thermostat

Economizer Logic Module

Rooftop Unit

Y1 Cool 1

Damper

Actuator

NO FREE

COOLING

AVAILABLE



Thermostat


Rooftop Unit

Y1 Cool 1

Damper

Actuator

FREE

COOLING

AVAILABLE



Thermostat


Rooftop Unit

Y1 Cool 1

Damper

Actuator

FREE

COOLING

AVAILABLE

Modulates

Open



Thermostat


Rooftop Unit

Y1 Cool 1

Damper

Actuator

FREE

COOLING

AVAILABLE

Modulates

Open

Y2



Thermostat


Rooftop Unit

Y1 Cool 1

Damper

Actuator

Modulates

Open

Y2

NO FREE

COOLING

AVAILABLE

Cool 2


Components in an Economizer System

•Logic Module

•Sensors

•Actuator


Economizer Sensors

C7150 Mixed Air Sensor

• Senses mixed air temperature and proportions dampers to maintain 55 degrees

• 3000 ohms at 25 deg C

C7400 Enthalpy Sensor

• Solid state humidity and temperature sensors

• Provide Enthalpy reading to economizer logic module

• Logic module uses this to determine if free cooling is available


Economizer Actuators

M7415 A and B ‘Black Motor’

• 25 Lb/in foot mounted spring return actuator

• ‘A’ model rotates CCW to open

• ‘B’ model rotates CW to open

• Motor position controlled by thermistor sensor resistance of C7150 mixed air sensor

M7215A ‘Black Motor’

• 25 lb/in foot mounted spring return actuator

• Rotates CCW to open

• Motor position controlled by 2-10VDC output from advanced economizer logic modules


W7459 Very Large installed base

Uses M7415 “black” motor exclusively

Typically mounted directly on actuator

Modulating signal based on resistance

from C7150 mixed air sensor

On board Potentiometers for min

position and enthalpy change over

W7459 Economizer Logic Module


W7212 Enhanced Economizer Logic Module

W7212 Offered the benefits of the W7459 with

added features:

Used any 0-10 or 2-10 volt actuator

Provided control of exhaust fans

Added occupancy input

Provided input for a CO2 sensor, allowed

demand controlled ventilation

Readily adopted by OEMS

Good opportunity for upgrade to

Demand Ventilation


What do Contractors say about Economizers?

• It is sometimes difficult to know if they are working properly

• They can be difficult to set up

• How do I know if the minimum position is set correctly?

• Am I providing too much or not enough ventilation to the building?

• They tend to get broken or damaged easily, don’t tend to last too long


JADE™ Economizer System Components


W7220 Economizer Interface and Programming

2 LINE LCD

16 CHARACTERS/LINE

SELECT (ENTER)

BUTTON SCROLL(UP/DOWN)

BUTTONS

MENU UP (EXIT)

BUTTON


Economizer System Sensors

C7400S Sylkbus sensors

C7250A 20k temperature sensors

3 position DIP switch


Kit part number:

50053060-001

Economizer Sensors Duct Mounting


W7220 Inputs / Outputs

Mixed Air Temperature

Outdoor Air Temperature

(when not using enthaply)

Enthalpy Sensor for MA/OA/RA

CO2 Sensor Inputs for DCV

2-10 vdc to actuator


W7220 Inputs / Outputs

Shut Down (Conventional)

O/B (Heat Pump

Auxiliary Output: -Exhaust 2

-ERV Enable

-System Alarm Output

Y1 In from Thermostat / Out to Equipment

24Vac System power

Y2 In from Thermostat / Out to Equipment

Occupancy Input

Exhaust 1

Earth Ground


W7459 Enthalpy Change Over Settings


W7220 Single Enthalpy Boundaries


Enthalpy Based System

Y2 in

Y2out

Y1out

Y2 in

Y2out

Y1out

Y1 in

Y1 Y2

Y1

N

Y2

OCC


Enthalpy Based System ~ No Free Cooling

Y2 in

Y2out

Y1out

Y2 in

Y2out

Y1out

Y1 in

Y1 Y2

Y1

N

Y2

OCC

No Free Cooling


Enthalpy Based System ~ No Free Cooling

Y2 in

Y2out

Y1out

Y2 in

Y2out

Y1out

Y1 in

Y1 Y2

Y1

N

Y2

OCC

No Free Cooling

Stage 1

Stage 2

1st Stage Cooling

2nd Stage Cooling


Enthalpy Based System ~ Free Cooling Avail

Y2 in

Y2out

Y1out

Y2 in

Y2out

Y1out

Y1 in

Y1 Y2

Y1

N

Y2

OCC

Free Cooling

Modulates Open...

...based on MA Setpoint

1st Stage Cooling

2nd Stage Cooling

Stage 1

After a predetermined

Amount of time

With Y2 calling...

Stage 2


JADE™ Economizer Efficiency is simply a breeze


•Top 5 Selling Points

-Simple to use

-Easy setup and maintenance

-Meets codes for maximum energy efficiency

-Enhanced quality for long life

-Lower total installed cost

The Value of JADE


JADE: Simple to Use

• Simplified installations - ‘Plain English’ used throughout

• Expanded information eliminates guessing - Damper ventilation settings are clear & readily available

• Elimination of added components – System Cost Savings - Ability to stage exhaust fans without extra hardware

- Less inventory for different models/ SKUs


JADE: Easy Setup & Maintenance

• Fault detection and diagnostics

- No more guessing

- LCD screen delivers clear fault messages and key diagnostic information

• Auto commissioning

- Saves valuable labor time and checks for wiring accuracy

- Eliminates tooling expense

• Simplified Wiring

- Removable connectors save time and eliminate wiring errors

- Sylkbus allows multiple sensors to sit on the same 2 wire pair


JADE: Meets Code Requirements

• Meets the new 2010 codes with the base model, and will be able to address future codes

• Code Adherence: CEC Title 24

- Level 1 - Min requirement to be sold in CA

- Level 2 - Energy Star

- Level 3 - Maximum Energy Efficiency Economizer self test or protocol for field test – Keypad or PC

Verification of initial operation at OEM or during commissioning – PC interface

- 15 year MTBF for economizer and economizer sensors


• No potentiometers; rugged push buttons

• Conformal coated for environmental protection

• Five year warranty for complete system

JADE: Enhanced Quality for Long Life


• Modular platform

- Saves equipment cost

- Enables more applications for less SKUs

• Advanced applications eliminates the need for additional components

- Additional cooling capacity and energy savings

- Elimination of freeze stat

- Ability to stage exhaust fans without extra hardware

JADE: Lower Total Installed Cost


How do I get JADE?

• Available as individual components

• Available as a ‘Retrofit Kit’

- Y7220S7215

Economizer module

Temperature and Enthalpy sensor

M7215 actuator

• Good Targets for Upgrade:

W859 T7400

Legacy Honeywell

Economizer Systems

Competitor’s

‘Orphaned’ systems

Systems that have been

neglected or aren’t working

H205


Building Ventilation

Why do we Ventilate Buildings?


Why do we Ventilate Buildings?

•The reasons we ventilate buildings are:

-To ensure a healthy atmosphere for occupants by diluting indoor contaminants and providing fresh air

-To pressurize the building positively to prevent unfiltered and unconditioned air from entering the building

-To provide cooling and save energy

-To replace exhausted air (provide make-up air)


Ventilation

Ventilation removes contaminants in a space through dilution....

• You can bring in lots of fresh air through your ventilation system to do this...

• ...but it costs a lot of money to bring in fresh air

• The answer is better control of fresh air!


ASHRAE Standards... May be Seen as Conflicting

•ASHRAE 62.1-2004 Ventilation for Acceptable Indoor Air Quality

- The purpose of this standard is to specify minimum ventilation rates and indoor air quality that is acceptable to human occupants

•ASHARE 90.1-2004 Energy Standard for Buildings Except Low-Rise Residential Buildings

-The purpose of this standard is to provide minimum requirements for the energy- efficient

design of buildings except low-rise residential


Demand Control Ventilation (DCV) is growing rapidly in popularity and required in many locations...

• CO2 does a good job of determining occupancy

• When tied in with an economizer, DCV can bring in the right amount of ventilation for the actual number of occupants

• This can save energy (money!) when spaces are not occupied at design densities

Demand Control Ventilation


How Demand Control Ventilation Works…

With a traditional economizer system, the required amount of fresh air is brought in based on the minimum position setting…

Damper Position

100% Open

Min Positon

0% Open



Damper Position

100% Open

Min Positon

0% Open

With a Demand Ventilation System there are three settings:

DCV SETPOINT

VENT MAX

VENT MIN

VENT Max Position

VENT Min Position

CO2 Level

450 ppm 800 ppm 2000 ppm *



Damper Position

100% Open

Min Positon

0% Open

VENT Min Position is set to provide enough fresh air to counteract off-gassing of building components

VENT Max Position

VENT Min Position

CO2 Level

450 ppm 800 ppm 2000 ppm *

As space CO2 level rises above DCV Setpoint dampers mod open, allowing more fresh air to bring CO2 down to setpoint

Dampers modulate open up to VENT Max Position (but do not exceed this position)



Damper Position

100% Open

Min Positon

0% Open

Savings are achieved by ventilating based on occupancy rather than by the building’s design ventilation requirement .

VENT Max Position

VENT Min Position

CO2 Level

450 ppm 800 ppm 2000 ppm *

Savings


How Much Ventilation Do we Need?

Occupant Component

Category Rp Discussion

0 0 CFM per person Applies to spaces where the ventilation requirements are dominated by building related sources, e.g., storage rooms and warehouses

1 5 CFM per person Applies to spaces where primarily adults involved in passive activities, e.g., office work

2 7.5 CFM per person Applies to spaces where occupants involved in higher levels of activities but not strenuous, e.g., lobbies and retail stores.

3 10 CFM per person Applies to spaces where occupants involved in more strenuous activities but not exercise level, e.g., most classrooms and other school occupancies.

4 20 CFM per person Applies to spaces where occupants involved in very high levels of activities or high contaminant generation, e.g. beauty salons, dance floors and exercise rooms.

Building Component Ra Discussion

1 0.06 cfm/ft2 Applies to spaces where building related contaminants are generated at rates similar to office spaces, e.g., conference rooms and lobbies.

2 0.12 cfm/ft2 Applies to spaces where building related contaminants are generated at rates significantly higher than office spaces, e.g., class rooms and museums.

3 0.18 cfm/ft2 Applies to spaces where building related contaminants are generated at even higher rates, e.g., laboratories and art classrooms.

4 0.30 cfm/ft2 Last two are for sports and entertainment category where there is no people based ventilation requirement, all building ventilation.

5 0.48 cfm/ft2 Source for data: ASHRAE Standard 62.1-2004 User’s manual 2005 edition


How Much Ventilation Do We Need?

Ventilation

For Occupant

Comfort

+ Ventilation

For Building

Component

= Ventilation

Required in

Building

Max Number of Occupants

X

Occupant Comfort

Factor

Building Area

X

Building Component

Factor


Demand Control Ventilation

Occupant Component

Category Rp Discussion

0 0 CFM per person Applies to spaces where the ventilation requirements are dominated by building related sources, e.g., storage rooms and warehouses

1 5 CFM per person Applies to spaces where primarily adults involved in passive activities, e.g., office work

2 7.5 CFM per person Applies to spaces where occupants involved in higher levels of activities but not strenuous, e.g., lobbies and retail stores.

3 10 CFM per person Applies to spaces where occupants involved in more strenuous activities but not exercise level, e.g., most classrooms and other school occupancies.

4 20 CFM per person Applies to spaces where occupants involved in very high levels of activities or high contaminant generation, e.g. beauty salons, dance floors and exercise rooms.

Building Component Ra Discussion

1 0.06 cfm/ft2 Applies to spaces where building related contaminants are generated at rates similar to office spaces, e.g., conference rooms and lobbies.

2 0.12 cfm/ft2 Applies to spaces where building related contaminants are generated at rates significantly higher than office spaces, e.g., class rooms and museums.

3 0.18 cfm/ft2 Applies to spaces where building related contaminants are generated at even higher rates, e.g., laboratories and art classrooms.

4 0.30 cfm/ft2 Last two are for sports and entertainment category where there is no people based ventilation requirement, all building ventilation.

5 0.48 cfm/ft2

Source for data: ASHRAE Standard 62.1-2004 User’s manual 2005 edition


Example:

• 5000 Sq ft office space

• 40 employees

• 1 rooftop unit, 5000 CFM capacity

Ventilation Requirement

• Occupant Component:

- Category 1: 5 cfm/ person = 200 CFM

• Building Component:

- Category 1: 0.06 cfm / sq ft = 300 CFM

• Total Fresh Air Requirement = 500 CFM

(10% of total CFM)


The formula for setting ventilation air

( OAT – RAT ) x % Ventilation air + RAT= MAT

OAT – Outside air temperature

RAT – Return air temperature

MAT – Mixed air temperature

Important! There should be at least a 10 degree difference

between the return and outside air temperature.


The formula for setting ventilation air

(( OAT – RAT ) x % Ventilation air) + RAT= MAT

OAT – Outside air temperature

RAT – Return air temperature

MAT – Mixed air temperature

Important! There should be at least a 10 degree difference

between the return and outside air temperature.

((80 - 68) x 10%) + 68 = ?

(12 x 10%) + 68 = ?

1.2 + 68 = 69.2


80° OA

Outdoor air reading taken at fresh air inlet

80

Unit not “calling ” for cooling


80° OA

68° RA

Return air temperature taken in return duct

68



80° OA

68° RA

69.2° MA

Slowly adjust minimum position until this reading

matches your calculations.

69



“Savings Estimator” Software

Not useful as an energy audit tool for a specific building, however allows user to study the impact of the following variables:

- Climate

- Building Size

- Occupancy schedule

- Utility rates

- Equipment efficiency

- Cost of controls

http://customer.honeywell.com/Business/Cultures/en-US/Products/Applications+and+Downloads/Economizer+Logic+Module+%28W7212%29+Simulator+and+Demand+Control+Ventilation+Savings-Estimator.htm


Savings Example adding DCV and Economizer

• 20,000 square foot retail store

• Located in Toronto

• 4 Rooftop units

• $ 0.08 / KWh

• $ 0.33 / M3 natural gas

• Currently has T874 Mechanical Thermostats

Result

• Gas usage goes from 8,700 to 4,000 M3

• Electrical usage goes from 24,000 Kwh to 16,000Kwh

• Utility savings of $2,182


Savings Example adding DCV and Economizer

• 4,000 square foot Casual Dining Restaurant

• Located in Toronto

• 2 Rooftop units

• $ 0.08 / KWh

• $ 0.33 / M3 natural gas

• Currently has T874 Mechanical Thermostats

Result

• Gas usage goes from 16K to 5.5K M3

• Electrical usage goes from 48 Kwh to 36 Kwh

• Utility cost savings of $4,500 per year


The End

Economizer Training - HVAC-Talk

Documents

Transcript of Economizer Training - HVAC-Talk