Greenheck Microprocessor Controller (475595 IOM) TAP v2.10 April 2014 (RVE, ERCH-01, ERT-01) - Manual (Page 32)

T
HIS SCREEN ALLOWS ADJUSTMENT OF THE
H
OT
G
AS
R
EHEAT
PI
CONTROL LOOP
.
This screen only appears if hot gas reheat was provided with the unit.
The controller utilizes a PI loop control for reheat. This allows for less sporadic
changes in supply air temperature, resulting in a smooth reaction to changing
conditions. To speed up reaction time, decrease the integration time. For slower
reaction time, increase the integration time. When making adjustments, make
them in small increments and test the system to determine if the new setting is
adequate prior to further adjustment. The band is the range that the integration
will occur between.
Hot Gas Controller
Integration: 300s
Band: 20°F
T
HIS SCREEN ALLOWS ADJUSTMENT OF THE HOT GAS REHEAT TIMERS
.
This screen only appears if ON/OFF hot gas reheat or hot gas reheat with flush
was provided with the unit.
If equipped with ON/OFF control, the minimum ON/OFF timers prevent short
cycling of the coil, allowing for better oil distribution through the DX system.
CONSULT THE FACTORY BEFORE CHANGING THE MINIMUM ON/OFF
TIMES.
For modulating valves that require a refrigerant flush, the controller will provide
a momentary flush of the hot gas reheat system. This prevents the build up of
oil in the reheat coil. The flush sequence starts by fully opening the reheat valve
for a period of Duration (Factory Default = 1 minute). Once the flush duration
is complete, the valve resumes modulation for a period of Flush cycle (Factory
Default = 30 minutes).
Hot Gas Reheat Timers
Hot gas reheat coil minimum
on/off time:
10min
Flush cycle: 30min
Duration: 1min
T
HIS SCREEN ALLOWS ADJUSTMENT OF THE DELAY BETWEEN HEAT AND COOL
MODES
.
This time delay prevents short cycling between heating, cooling and/or
economizer modes.
Heat/Cool Delay
Time delay between heating,
cooling &/or economizer
modes. Delay:
180s
T
HIS SCREEN ALLOWS ADJUSTMENT OF THE
S
UPPLY
R
ESET
PI
CONTROL LOOP
,
FOR
R OOM T EMP C ONTROL .
This screen only appears if a Room Temp Sensor is wired to the controller.
The controller utilizes a PI loop control for supply reset based on room temp.
This allows for less sporadic changes in supply air temperature, resulting in a
smooth reaction to changing conditions. To speed up reaction time, decrease
the integration time. For slower reaction time, increase the integration time. When
making adjustments, make them in small increments and test the system to
determine if the new setting is adequate prior to further adjustment. The band is
the range that the integration will occur between.
Supply Reset Control
Integration: 1200s
Band: 10°F
Mod Hot Gas Setup
Minimum ON: 4.0vdc
Maximum ON: 10.0vdc
T
HIS SCREEN ALLOWS ADJUSTMENT OF THE MODULATING HOT GAS REHEAT
.
This screen appears if modulating hot gas reheat was provided (except heat
pump).
32 DDC Controller for Tempered Air Products
®