13
START-UP
Differential Enthalpy Switchover Strategy —
On cer-
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$er damper is maintained at its
current value.
0
200
400
600
800
1000 1200 1400 1600
FLOW (CUBIC FEET/MINUTE)
0.5
0.4
0.3
0.2
0.1
0
ST
A
TIC PRESSURE (IN. WG)
0
400
800
1200
1600
2000
2400
FLOW (CUBIC FEET/MINUTE)
0.5
0.4
0.3
0.2
0.1
0
ST
A
TIC PRESSURE (IN.WG)
ST
A
TIC PRESSURE (in. wg)
0.25
0.20
0.15
0.10
0.05
0.00
0
200
400
600
FLOW IN CUBIC FEET PER MINUTE (cfm)
800
1000
Fig. 41 — 3 to 6 Ton Barometric Relief Capacity
(Vertical EconoMi$er)
Fig. 42 — 7
1
/
2
to 12
1
/
2
Ton Barometric Relief
Capacity (Vertical EconoMi$er)
Fig. 43 — Barometric Flow Capacity
3 to 6 Ton
7
1
/
2
to 12
1
/
2
Ton
Fig. 44 — Outdoor Air Leakage
3 to 6 Ton
7
1
/
2
to 12
1
/
2
Ton
FLOW IN CUBIC FEET
PER MINUTE (cfm)
STATIC PRESSURE (in. wg)
0.00
0.10
0.20
0.30
0.40
0.50
80
60
40
20
0
FLOW IN CUBIC FEET PER MINUTE (cfm)
0
1000
2000
3000
4000
5000
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
ST
A
TIC PRESSURE (in. wg)
Fig. 45 — Return Air Pressure Drop
3 to 6 Ton
7
1
/
2
to 12
1
/
2
Ton
