Reznor FX05 User Manual

Form CP-MAPS-D12 with FX05, Page 6
oH1 = 68°F, Outside Air Temperature <68°F HEATING
oC1 = 62°F, Outside Air Temperature >62°F COOLING
Unit in
cooling mode -
space temperature
can change to
heating mode.
Unit in
heating mode -
space temperature
can change to
coolting mode.
FIGURE 3 - Reverse Lockout Values to switch between heating and cooling based on
space temperature (instead of outside air temperature).
If the lockout values are reversed as shown in FIGURE 3,
and a space sensor (CL53) is installed, the unit will switch
between heating and cooling modes based upon space
requirements. Example: If the outside air temperature
rises from 50ºF to 65ºF, the unit will be in cooling mode.
If the space sensor calls for heating when the outside air
temperature is 65ºF, the unit will switch to heating mode.
Once the space is satised, the unit will operate in heat-
ing mode for neutral air control. The unit will not switch to
cooling mode until the space sensor calls for cooling.
Heating Mode
When the unit is in heating mode, the unit will discharge air based upon the
neutral air discharge heating setpoint point (dHL) or the room discharge air
heating setpoint (rHP). If the space sensor is not installed, the unit will operate
to provide neutral air only.
If a local space sensor is installed, the unit will change the neutral air discharge
setpoint to the room discharge air heating setpoint (rHP) whenever the space
requires heating. Whenever the space temperature is below the setpoint by
a value greater than the space heating proportional band (SHP), then space
heating is required. The SHP default value is 1.8ºF, adjustable from 1 to 8 ºF.
Example:
Space heating setpoint = (SSP - Hso) = 75ºF - 5ºF = 70ºF
Space heating proportional band (SHP) = 1.8ºF (Range 1 to 8ºF)
Space heating active [(SSP - Hso) - SHP]: 70ºF - 1.8ºF = 68.2ºF
Room discharge air temperature heating setpoint (rHP) = 80ºF
During the Unoccupied Cycle the space setpoints will increase as follows:
Space Heating Setpoint = (SSP - Hso - SHP - nSb) = 75°F - 5°F - 1.8
- 9°F = 59.2°F
(nSb default value = 9°F; adjustable from 0 to 35°F )
When the space temperature is more than SHP above the setpoint (71.8ºF),
the unit will switch to neutral air control and space heating requirements will be
OFF. The neutral discharge air control setpoint value will be the dHL value.
It may be useful to change the neutral air setpoint if the indoor ambient comfort
conditions signicantly change based upon outdoor air conditions. The dis-
charge air setpoint can be set to automatically adjust between the dHL and the
dHH values depending upon the outside air conditions. Example: Elder care
centers tend to require higher space temperatures during the winter season
Heating and
Cooling Control
Modes (cont’d)
When the space temperature sensor is satised (or not installed), the unit will
discharge standard (neutral) air. The default cooling mode setpoint (dCH) value
is 70ºF. The default heating mode setpoint (dHL) is 70ºF. These setpoints can
automatically be adjusted by a user dened reset schedule.
The heating or cooling mode is determined by outside air conditions and mode
lockout values. If the outside air temperature value (Point AI-3) is greater than
the cooling mode lockout value (oC1, default 68°F), unit is in cooling mode. If
the outside air temperature is lower then the heating mode lockout value (oH1,
default 62°F), unit is in heating mode (gas or electric).
Unit is in Cooling Mode when outside air temperature
rises above oC1
Unit is in Heating Mode when outside air temperature
falls below oH1
NOTE: If a space sensor is not installed, this function is not available.

Reznor FX05 Specifications

General

Brand	Reznor
Model	FX05
Category	Computer Hardware
Language	English