McQuay MicroTech II Operation & Maintenance

OM 750 Page 15 of 32
Econ State (state number 3)
The Econ state is a “normal” state that the UVC can go into when Cool
mode is active. The Econ state is typically active in the Cool mode
when primary cooling (economizer) is available and adequate to meet
the cooling requirements.
Transition (Econ = Available AND Mech Cooling
≠ Available)
into State OR
(Space ≠ High CO
2
AND Heat PI = Saturated Low
AND DAT > VCLL)
OR
((Mech PI = Saturated Low AND Econ Mech Timer =
Expired) OR (Mech Cooling ≠ Available))
Operation When the Econ state becomes active, the UVC will
within State use economizer cooling (see Economizer Operation)
as needed to maintain the effective cooling setpoint
(see Space Temperature Setpoints). The Econ Timer
(3-minutes fixed) will begin counting. The UVC will
monitor the DAT to ensure it does not fall below VCLL
(see Ventilation Cooling Low Limit) setpoint. The
CO
2
demand controlled ventilation function will be
active, if the unit is equipped for CO
2
control (see CO
2
Demand Controlled Ventilation), and the OA damper
will be adjusted as needed to maintain the CO
2
setpoint.
The UVC will remain in this state until one of the
transition out conditions become true, or until one of
the super state transition out conditions becomes true.
Transition (Econ ≠ Available AND Mech Cooling ≠ Available)
out of State OR
(Space = High CO
2
OR DAT < VCLL)
OR
(Econ Timer = Expired AND Econ PI = Saturated High
AND MechCool = Available)
OR
(Econ ≠ Available AND Mech Cooling = Available)
Figure 14. Econ State Operation (Occupied Mode and Auto Fan)
Figure 15. Econ Mech State Operation (Occupied Mode
and Auto Fan)
Econ Mech State (state number 1)
The Econ Mech state is a “normal” state that the UVC can go into when
Cool mode is active. The Econ Mech state is typically active in the Cool
mode when primary cooling (economizer) alone is not adequate to
meet the cooling requirements and both primary cooling and secondary
cooling (compressor) are available.
Transition (Econ Timer = Expired AND Econ PI = Saturated
into State High
AND Mech Cooling = Available)
OR
(Econ = Available)
Operation When the Econ Mech state becomes active, the OA
within State damper will be set to 100% open, and the UVC will use
the unit’s mechanical cooling capabilities (see
Compressor Operation) as needed to maintain the
effective cooling setpoint (see Space Temperature
Setpoints). The Econ Mech Timer (3-minutes fixed)
will begin counting. The UVC will monitor the DAT
to ensure it does not fall below MCLL (see Mechanical
Cooling Low Limit) setpoint.
The UVC will remain in this state until one of the
transition out conditions become true, or until one of
the super state transition out conditions becomes true.
Transition ((Mech PI = Saturated Low AND Econ Mech Timer =
out of State Expired) OR (Mech Cooling ≠ Available))
OR
(Econ ≠ Available)

McQuay MicroTech II Specifications

General

Brand	McQuay
Model	MicroTech II
Category	Controller
Language	English