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SUBMITTAL
FORM NO. 2895-10P
MicroMetl
DATE: 2/12
SUBMITTED TO
COMPANY:
Down Discharge Economizer with 100% Relief
Capability for Carrier 48/50TC A/B04-A/B07;
50TCQ A04-A07; 48/50LC,HC A04-A06; 50HCQ A04-A06;
48/50TF,TM,HJ,TFQ 004-007; 48/50HE 003-006 Units
0688-0101 Static Pressure Loss
Through Economizer
DRAWN BY:
JOB NAME:
EQUIPMENT:
NOTES:
FEATURES:
• Gear driven dampers eliminate slippage associated with
standard linkage.
• Designed specifically for down discharge applications. Easy to
install. Easy to service.
• Lower static pressure loss through economizer dampers.
• Greater barometric relief capabilities.
• Factory assembled rainhood with aluminum filters in both
outside air and relief hoods.
• Uses filter access door shipped with HVAC unit.
• Rainhoods are sloped for
water run-off.
• Hardware cloth over
relief damper.
Part Number:
0688-0101
0688-0101 Barometric Relief
ECONOMIZER PART NO.S
0688-0101-00920
Economizer w/ no controls
0688-0101-9J920
Economizer w/ fixed
dry bulb controls
0688-0101-54920
Economizer w/ modulating
enthalpy controls
0688-0101-9A920
0688-0101-9J920-A
Economizer w/ modulating
adjustable dry bulb controls
Access door
shipped with
HVAC unit
Drive gear
attached to
the motor
Side View
Filters
Economizer motor
and harness
Weight: 63 lbs
Gear driven
dampers
19 1/4"
Evaporation
coil
Sloped
Economizer includes
Honeywell W7212
controller capable of CO2,
demand control and power
exhaust control.
Rainhood ships
fully assembled
Outside
air
Aluminum water entrainment filters
Relief air
THIS DOCUMENT IS THE PROPERTY OF MICRO METL CORPORATION AND IS DELIVERED UPON THE EXPRESS CONDITION THAT THE CONTENTS WILL NOT BE DISCLOSED OR USED WITHOUT MICRO METL'S WRITTEN CONSENT.
MICROMETL CORPORATION • 3035 N. SHADELAND AVENUE, SUITE 300 • INDIANAPOLIS, IN. 46226 • 1-800-662-4822 ••• MICROMETL WEST • 905 SOUTHERN WAY • SPARKS, NV 89431 • 1-800-884-4662
INSTALLATION INSTRUCTIONS
MicroMetl
For 0688-0101, 0201
Down Discharge Economizer
INSTRUCTIONS:
STEP #1
ILL. #1
Top filter access door
shipped with HVAC
unit. This door is used
with the economizer
1A. Disconnect power to HVAC until
1B. Remove top filter door, shipped on
HVAC unit. Set aside for use later.
Remove and discard the lower panel
shipped with HVAC unit.
Save
HVAC unit’s
lower panel.
Remove and
discard.
STEP #2
this
pane
l
Disc
ard t
pane his
l
2A. Unpack the MicoMetl economizer.
2B. Remove discharge air sensor (yellow)
from economizer and install in supply air
chamber/duct. (page 2, ILL. 10)
2C. Slide economizer into return air chamber,
being sure not to pinch harness (ILL. 2).
Rear flange of economizer slides under
tab on duct flanges. (See Rear Flange
Detail.) Secure economizer in place
through mating holes.
ILL. #2
Unit
STEP #3
3A. The 0688-0201 hood requires field
assembly of the divider/base to the sides
using the provided pre-punched holes.
The 0688-0101 is factory assembled.
3B. Install rain hood per (ILL> 2 & 4). Line up
pre-punched holes in hood with holes in
HVAC unit and install screws. Install
aluminum filter in hood. (ILL. 5)
Economizer Specification (in inches)
MicroMetl
Part No.
A
3-6 ton
0688-0101
19 1/4
7½-12½ ton
0688-0201
29 3/8
Unit Size
3C. Install HVAC unit filter access door over
rain hood.
3D. Motor and logic access provided behind
filter access door.
Rear Flange Detail
ILL. #3
Filter
Rain hood
Economizer
Slide economizer
rear flange into tab
Slide filter
under screws
Rain Hood
Use clips
to hold
filter in place
Economizer
Unit base
MMC
Economizer clip
on HVAC unit
Installation hook
on the hood
Hood Latch Detail
ILL. #4
3035 N. Shadeland Ave, Suite 300 Indianapolis, IN. 46226
MMC WEST
ILL. #5
202 South 18th. St. Sparks, NV. 89431
Manufacturer reserves the right to discontinue, or change at any time, specifications,
designs and prices without notice and without incurring obligations.
1
Form No. 2901-5P
Copyright MicroMetl Corporation 2003 All rights reserved
STEP #3
-
IMPORTANT! - please read!
Use 1 of the next 2 pages to wire the economizer.
To determine which page to use, check outdoor
sensor type. Compare sensor type to wiring
instruction description at top of each page. Cycle
test and adjust.
0688-0101 Static Pressure Loss
Through Economizer
0.400
0.350
0.2
Static Pressure
Static Pressure (in. w.g.)
0.25
Return Air
0.15
0.1
Outside Air
0.05
0
0688-0201 Static Pressure Loss
Through Economizer
0.300
Return Air
0.250
0.200
0.150
Outside Air
0.100
0.050
0
500
1000
1500
2000
2500
0.000
3000
0
Airflow (cfm)
1000
2000
3000
Airflow (cfm)
0688-0100 Barometric Relief
3000
Relief Airflow (CFM)
2500
2000
1500
1000
500
0
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
Static Pressure (in w.g.)
ILL. #6
ILL. #7
Side View
Filter access door shipped
with HVAC unit. Lift up
and out to remove.
Outside air hood
Mount
discharge
sensor here
Indoor Blower
HVAC Unit Filter
Always disconnect power
before changing filters
2
4000
5000
6000
Wiring Instruction for Use with 12 Pin Plug Enthalpy and Dry Bulb
PLEASE READ CAREFULLY!
Terminal Board
9962-0305 Wiring Harness
with 12 pin plug
Follow these instruction if the economizer
wiring harness in the HVAC unit has a 12
pin plug.
Factory installed
harness
ILL. #6
Factory attached
to terminal board
Control
compartment
IMPORTANT!
Economizer
and hood
CONTROL SYSTEMS NOTES:
1. The HVAC unit has an economizer wiring harness factory installed. It attaches to the 9962-0305 economizer harness on one end
and is factory attached to the unit’s terminal board on the other end (ILL. #6).
2. The 9962-0047 pigtail and the 9962-0073 adaptor harness are available from factory for obsolete units with 9 pin plug.
9962-0305 Wiring Harness
WIRING INSTRUCTION for use with 12 pin economizer plug.
STEP #4
• Plug the economizer’s 9962-0142
wiring harness into the HVAC unit’s
harness
ILL. #6
Thermostat
Connection Board
Red
1
STEP #5
NOTE: There are (4) loose wires
available in the HVAC unit. Connect
the pink and violet wires to the
discharge sensor. Do not use the brown
and white wires.
4
4
Maintains mixed air temperature
between 50O-56O.
To compressor lockout
“1” on HVAC unit
MicroMetl discharge
sensor (mount in blower
compartment)
To compressor lockout
“2” on HVAC unit (if 2
stage is used)
Connect the pink and violet
wires to the discharge sensor. Do
not use brown or white wires
Do
not use
Brw
Plug harness installed
in HVAC units
3
Compressor lockout switch on
some models. Lockouts out
compressors at 35O F (+/- 5O)
Field wire if desired.
Remove this jumper / resistor
when using differential enthalpy.
2
• Mount the MicroMetl discharge
sensor in the unit blower
compartment. (See ILL. 6)
If using differential enthalpy,
setpoint should be at “D”.
Enthalpy or
adj. dry bulb
MicroMetl economizer
harness / plug
620 OHM
Resister
Actuator
Logic
+
SR
Exhaust Fan Set Point
Minimum Position
Setting
DCV / CO2 maximum
setpoint
Red
DCV / CO2 activation
setpoint
Power exhaust fan
connection
To optional
CO2 sensor
EF
EF1
AQ
AQ1
Black
N
24V
HOT
3
Enthalpy
changeover
setpoint
1
Fixed Dry Bulb Wiring Instruction for Use with 12 Pin Economizer Plug
PLEASE READ CAREFULLY!
Terminal Board
9962-0307 Wiring Harness
with 12 pin plug
Follow these instruction if the economizer
wiring harness in the HVAC unit has a 12
pin plug.
Factory installed
harness
ILL. #10
Factory attached
to terminal board
Control
compartment
IMPORTANT!
Economizer
and hood
CONTROL SYSTEMS NOTES:
1. The HVAC unit has an economizer wiring harness factory installed. It attaches to the 9962-0307 economizer harness on one end
and is factory attached to the unit’s terminal board on the other end (ILL. #10).
2. The 9962-0047 pigtail and the 9962-0073 adaptor harness are available from factory for obsolete units with 9 pin plug.
Fixed Dry Bulb - 9962-0307 Wiring Harness
WIRING INSTRUCTION for use with 12 pin economizer plug.
STEP #4
• Plug the economizer’s 9962-0086
wiring harness into the HVAC unit’s
harness
ILL. #14
Thermostat
Connection Board
1
Red
2
STEP #5
• Mount the MicroMetl discharge
sensor in the unit blower
compartment. (See ILL. 6)
3
NOTE: There are (4) loose wires
available in the HVAC unit. Connect
the pink and violet wires to the
discharge sensor. Do not use the brown
and white wires.
4
5
Enthalpy changeover potentiometer not used with fixed
dry bulb
Compressor lockout switch on
some models. Lockouts out
compressors at 35O F (+/- 5O)
Field wire if desired.
If replacing the fixed dry bulb
with either an adjustable dry
bulb or enthalpy sensor, the 620
OHM resistor must be removed.
Fixed dry bulb allows for free
cooling when outside temperature is less than 70O.
Maintains mixed air temperature
between 50O-56O.
MicroMetl discharge
sensor (mount in blower
compartment)
To compressor lockout
“1” on HVAC unit
Connect the pink and violet
wires to the discharge sensor. Do
not use brown or white wires
To compressor lockout
“2” on HVAC unit (if 2
stage is used)
Do
not use
Brw
5
Plug harness installed
in HVAC units
Enthalpy or
adj. dry bulb
620 OHM
Resister
MicroMetl economizer
harness / plug
Actuator
Logic
+
SR
Red
Exhaust Fan Set Point
Minimum Position
Setting
DCV / CO2 maximum
setpoint
DCV / CO2 activation
setpoint
Power exhaust fan
connection
To optional
CO2 sensor
EF
EF1
AQ
AQ1
Black
N
24V
HOT
4
Enthalpy
changeover
setpoint
1
MicroMetl Integrated Economizers
The purpose of an economizer is to use outdoor air for cooling,
whenever possible, to reduce compressor operation.
During the unoccupied period, the actuator will override minimum
position setting and drive fully closed. On a loss of power, the
actuator will spring return fully closed.
The economizer system initially responds to a signal from the
cooling thermostat and functions as a true first stage for cooling, while providing maximum fuel economy. The economizer
automatically locked out during the heating mode and holds the
outdoor air damper at the minimum position settings.
When in heating operation, or when outdoor air temperature or
enthalpy conditions are high, economizer operation is locked out,
and actuator os held at minimum position.
The staging relay is used when the first stage compressors must
provide mechanical cooling when assisting the economizer.
During the occupied period, on a call for cooling, when outdoor
air temperature or enthalpy conditions are low, the economizer
actuator will proportion to maintain between 50O F and 56O F at
thermistor discharge sensor.
The staging relay can be omitted when the second stage
compressors can be used to assist the economizer with
mechanical cooling.
If the mixed or discharge temperature is above 56O F, actuator
will open to admit additional outdoor air until the temperature
return to the 50O to 56O F range. If the mixed or discharge air
temperature is below 50O F, the actuator will proportion closed,
shutting the outdoor air damper until the temperature returns to
the 50O to 56O F range. During the occupied period, the actuator
will not close past the minimum position. If the fully open
actuator cannot satisfy the space demand, mechanical cooling is
sequenced on.
5
Component Description
6
1
4C
3
4A
2
4B
5
1. Damper actuator ...9901-1865 provides 24v modulating
control of economizer damper, 25 in. lb. of torque,
(Honeywell M7215a-1008)
4A. Entahlpy sensor ...9901-0018 senses and combines temperature and humidity of outdoor air. And also provides the signal to the economizer logic. (Honeywell C7400A used on 1008-0100)
2. Discharge sensor ...9901-0001 provides a signal (3000
Ohms at 25O C or 77O F) to the actuator during free cooling
or economizer mode. The signal opens the economizer
damper until the discharge temperature drops below 55O.
At this time the signal causes the motor to modulate the
damper and mix outside air with return air to maintain a 50O
F to 56O F discharge temperature.
4B. Adjustable dry bulb ...9901-2251 senses temperature of outside air and provides signal to the economizer logic. (Honeywell C7660A-1001 used on 1009-0100)
4C. Fixed dry bulb ...9901-0183 senses temperature of outside air. If below 70O setpoint, allows for free cooling.
3. Economizer logic ...9901-1805 accepts input from discharge
sensor and outside air sensor. Analyzes input to control
actuator modulation and economizer switching. Logic
also houses minimum position adjustment, enthalpy or
adjustable dry bulb adjustment, power exhaust control, and
CO2 demand control ventilation adjustment. When used
with optional differential sensor in the return air, the logic is
capable of selecting the most economical air available for
cooling. (Honeywell W7212-C)
6
5.
Wire harness color coded and pre-wired to actuator and economizer logic.
6.
Compressor lockout ...9901-0252 locks out compressor when temperature falls below 35O F (+/- 5O F). Shipped with economizer, but must be field wired, if desired.