Start-Up; Differential Enthalpy Switchover; Strategy; Operating Sequence - Carrier CRECOMZR 004A01 Series Installation Instructions Manual

0.5
0.4
0.3
0.2
0.1
0
0 200 400 600
FLOW (CUBIC FEET/MINUTE)
Fig. 41 — 3 to 6 Ton Barometric Relief Capacity
(Vertical EconoMi$er)
0.5
0.4
0.3
0.2
0.1
0
0 800
400
FLOW (CUBIC FEET/MINUTE)
Fig. 42 — 7 1 / to 12 1 /
2 2
Capacity (Vertical EconoMi$er)
0.25
0.20
0.15
0.10
0.05
0.00
400
0 200
FLOW IN CUBIC FEET PER MINUTE (cfm)
3 to 6 Ton
7 1 / to 12 1 / Ton
2 2
Fig. 43 — Barometric Flow Capacity
80
60
40
20
0
0.00 0.10
0.20
STATIC PRESSURE (in. wg)
3 to 6 Ton
1 1
7 / to 12 / Ton
2 2
Fig. 44 — Outdoor Air Leakage
800 1000 1200 1400 1600
1200 1600 2000 2400
Ton Barometric Relief
600 800 1000
0.30 0.40 0.50
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
1000
FLOW IN CUBIC FEET PER MINUTE (cfm)
3 to 6 Ton
1 1
7 / to 12 /
2 2
Fig. 45 — Return Air Pressure Drop
Differential Enthalpy Switchover Strategy —
tain EconoMi$er controller models, the differential enthalpy
switchover strategy must be enabled manually.
To determine the controller model, refer to the label on the
front of the controller. Models AD-DME1701-0 require no
commissioning for differential enthalpy switchover strategy.
Models AD-DME1701-1 or AD-DME1711-1 require manual
configuration.
To enable differential enthalpy: Press and hold the CONFIG
button for more than 30 seconds, then release. The light-
emitting diode (LED) flashes twice and the controller resumes
normal operation. To return to single enthalpy mode, press and
hold the CONFIG button for more than 30 seconds, then re-
lease. The LED flashes once and the controller resumes normal
operation.

Operating Sequence

COOLING — When the Outdoor Air Temperature (OAT) is
above the ECON SP set point and the room thermostat calls for
Stage 1 cooling (R to G + Y1), the indoor-fan motor (IFM) is
energized and the EconoMi$er damper modulates to minimum
position. The compressor contactor is energized starting the
compressor and outdoor-fan motor (OFM). After the thermo-
stat is satisfied, the damper modulates to the fully closed posi-
tion when the IFM is deenergized.
When the OAT is below the ECON SP setting and the room
thermostat calls for Stage 1 cooling (R to G + Y1), the
EconoMi$er modulates to the minimum position when the
IFM is energized. The EconoMi$er provides Stage 1 of cooling
by modulating the return and outdoor air dampers to maintain a
55 F supply air set point. If the supply-air temperature (SAT) is
greater than 57 F, the EconoMi$er modulates open, allowing a
greater amount of outdoor air to enter the unit. If the SAT drops
below 53 F, the outdoor-air damper modulates closed to reduce
the amount of outdoor air. When the SAT is between 53 and
57 F, the EconoMi$er maintains its position.
If outdoor air alone cannot satisfy the cooling requirements
of the conditioned space, and the OAT is above the MECH
CLG LOCKOUT set point, the EconoMi$er integrates free
cooling with mechanical cooling. This is accomplished by the
strategies below.
NOTE: Compressors have a two-minute Minimum On, Mini-
mum Off, and Interstage delay timer.
1. If Y1 is energized, and the room thermostat calls for
Y2 (2-stage thermostat), the compressor number 1 and
OFM are energized. The position of the EconoMi$er
damper is maintained at its current value.
2. If Y1 is energized for more then 20 minutes, and Y2 is
not energized (whether or not a 2-stage thermostat is
used), compressor no. 1 and OFM are energized. The
position of the EconoMi$er damper is maintained at its
current value.
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2000 3000 4000
Ton

START-UP

5000
On cer-