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Bryant Durapac Plus Series 551a User Manual

Page 15

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15

H. Ventilation Air (Minimum Position Set Up)

If ventilation air is not required, skip this section. If ventila-
tion air is required, perform the following:

1. The indoor fan must be on to set the ventilation air.

Either put the thermostat in the continuous fan mode
or jumper the R and G terminals at the rooftop unit
connection board.

2. Locate the minimum position (MIN POS) potentiome-

ter. Turn the potentiometer full CCW to fully close
the outdoor air dampers. Turn the potentiometer
gradually clockwise (CW) to the desired position. See
Fig. 16.

3. Replace the filter access panel. See Fig. 18. Ensure

the filter access panel is securely engaged.

4. Calculate the minimum airflow across the

EconoMi$er.

a. Calculate % of outside air using the following

formula.

% Outdoor air through EconoMi$er

b. Multiply total CFM by percentage outdoor air,

this gives outdoor air volume in CFM.

IX. STEP 9 — INSTALL ALL ACCESSORIES

After all the factory-installed options have been adjusted,
install all field-installed accessories. Refer to the accessory
installation instructions included with each accessory.

A. Motormaster® I Control Installation (551A155 and 180
Only)

Install Field-Fabricated Wind Baffles

Wind baffles must be field-fabricated for all units to ensure
proper cooling cycle operation at low ambient temperatures.
See Fig. 25 for baffle details. Use 20-gage, galvanized sheet
metal, or similar corrosion-resistant metal for baffles. Use
field-supplied screws to attach baffles to unit. Screws should
be

1

/

4

-in. diameter and

5

/

8

-in. long. Drill required screw holes

for mounting baffles.

% Outdoor
air

=

Mixture Temp – Return Air Temp
Outdoor Temp – Return Air Temp

WARNING:

Personal Injury Hazard. Avoid possible

injury by keeping fingers away from damper blades.

CAUTION:

To avoid damage to the refrigerant coils

and electrical components, use recommended screw sizes
only. Use care when drilling holes.

20 mA LED

1k ohm Potentiometer

2 to 10 VDC at

0 to 2000 ppm

CO2 Sensors:

Rem ote

M inim um Position

Rem ote

LED

Outdoor Air Enthalpy

CROUTENT001A00

Return Air Enthalpy

CRRETENT001A00

Line

Voltage

CO
CO
COM
DAT
COM
REM
POT
COM
LED
COM

2
2

OAT
COM
OAH
+15V
RAT
COM
RAH
+15V

C

O

M PW

O

U

T T

T

Violet

C

O

M PW

O

U

T T

T

Violet

Field-supplied W iring

W iring Included

470 ohm

5 watt

Resistor

24 VAC m ust be present

on BI for the system to be

unoccupied.

Unoccupied Control

(Part num ber on the control

m ust be AD-DM E1701-1

or AD-DM E1711-1.)

Unoccupied

Contact

Tan
Violet
W hite
Red

Tan
Violet
W hite
Red

24 V

A

C

20 V

A

NOT

USED

1

2

-

(+)

CRCDXSEN004A00

Fig. 24 — Typical EconoMi$er Sensor Wiring