McDaniel Metals DDNECNJ180240 Installation Manual

281-987-8400 • 281-987-9494 (fax)

1318 Buschong, Houston, TX 77039

www.mcdanielmetals.com

ECONOMIZER 101

Economizers are designed to provide “free” air condioning
when outside condions are appropriate. When the outside air
is cool and dry enough, the economizer automacally opens to
introduce the cool air to the interior space, thereby eliminang
the need to run the air condioning compressor.

If the outside air becomes too warm or humid, the economiz-

er automacally closes the fresh air damper and the compressor
engages to begin cooling the space mechanically.

If a two stage thermostat is used it is possible to use a combi-

naon of economizer and mechanical cooling to condion the
space.

The economizer can also be set to allow a minimum amount
of fresh air to enter the space when the equipment’s indoor

blower is operang.

Economizers are valuable tools to enhance indoor air qual-

ity, save energy and prolong the life of the air condioning

equipment.

DDNECNJ180240

DOWNFLOW JADE ECONOMIZER
FOR DAIKIN DCG180-240 AND
DCC180-240

to cool the space. (Go to step 5.)

4. Outdoor air dampers open to minimum posion and the
compressor engages to provide mechanical cooling.

5. When the thermostat is sased the outside air dampers
return to a closed posion.

INSTALLATION

1. Open the containers and inspect the contents for shortages
and damage.

2. Remove the large evaporator access panel from the package
unit and discard. Remove the smaller lter access panel.

3. Slide the base plate into the opening with the wider ange

toward the outside of the unit and place it over the return

air opening. It should be centered between the evaporator
opening side posts. (Figure 1)

4. Slide the damper rack into the large opening unl the front
ange is against the evaporator support bracket. (Figure 2)

Figure 1

SEQUENCE OF OPERATION

This sequence assumes employment of a single enthalpy

economizer using a two stage thermostat.

1. A call for cooling comes from room thermostat.

2. The enthalpy sensor determines if the atmospheric condi-
ons are conducive for using outside air for cooling. If YES,
go to step 3. If NO, or if outdoor air temperature rises above
enthalpy set point, go to step 4.

3. The outside air dampers open and modulate to maintain a

mixed air temperature (outside air + indoor air) of 53 de­grees F. If the outdoor air is insucient to sasfy the ther­mostat alone and a second stage of cooling is required, the

rst stage compressor starts and works in conjuncon with

the economizer

Figure 2

6. Slide the damper rack to the right unl the damper side
anges are even with the evaporator access panel opening
ange. The top ange of the damper rack should be even
with or just inside the top cap of the unit. (Figure 3&4)

REV. B Effective 3-28-2014

Figure 4

Figure 3

MINIMUM SET POINT EQUATION

(To X OA) + (Tr X RA) = Tm
To = Outdoor air temperature
OA= Percent of outdoor air
Tr = Return air temperature
RA= Percent of return air

Tm= Resulng mixed air temperature

Example:

Fresh air required is 10% outdoor air.
Outdoor air temperature is 60 degrees F.
Return air temperature is 75 degrees F.
(0.1 X 60) + (0.9 X 75) =

6.0 + 67.5 = 73.5

Mixed air temperature will be 73.5 degrees F when the
OA is 60 degrees F and the RA is 75 degrees F with 10%
outdoor air.

CONTENTS

Figure 5

6. Remove the mist eliminator lters from the fresh air/
barometric relief hood.

7. Install gasket material on the front of the top ange of
the hood assembly.

8. Install gasket material on the inside of the side anges
of the hood assembly.

9. Install the hood assembly taking care to slide the top
ange of the hood under the top cap of the unit.

10. Secure the hood with the screws provided.

11. Reinstall the mist eliminators and secure them using the
latches provided.

12. Locate the unit economizer 9 pin plug inside the evapo­rator secon near the lter access opening and plug it
into the corresponding 9 pin plug on the economizer.

NOTE: Ensure neither the wire nor the plugs interfere with

the movement of the dampers during operaon.

13. Remove the blower access panel on the unit and install

the mixed air sensor on the blower housing toward the
outside edge ensuring that the screws do not interfere

with the blower wheel. (Figure 5)

14. Connect the pink mixed air sensor wire to the sensor
and then feed the pink wire back to the Jade control and
connect it on the MAT terminal.

15. Seal the hood using silicone or other approved method
to ensure a water ght seal

16. Replace the blower and lter access panel.

1 Base plate
1 Damper rack w/ economizer controls
1 Fresh air hood
2 Mist eliminator
1 Screw package and control jumpers
1 Installation Instructions and Component

Manual

ACCESSORIES / CAPABILITIES

Dual Enthalpy - Requires an addional C7400 enthalpy
control installed in the return air duct.

Demand Control Venlaon - Requires a CO2 sensor.

Power Exhaust - DPE180240X power exhaust used in
applicaons where barometric relief is not sucient.

Important Notes

Please see enclosed brochure for Honeywell component

trouble shoong and conguraon instrucons.

The fresh air mist eliminator should be ushed periodi­cally with warm soapy water.

A two stage thermostat is recommended with this acces­sory.