Sequence Of Operation; Terminology; Power On-Control Input "Occupied - Trane RRU120 D B Series Installation, Operation And Maintenance Manual

Sequence of Operation

Terminology

Controls
RRUCM RRU Main Control Module
ROD Remote Operator Display
DES Outdoor Damper End Switch
APS Air Proving Switch
FFS Fan Failure Switch
RCC Refrigeration Capacity Controller
MGA Modulating Gas Actuator
GV Gas Valve
IGN Ignition Control Module
TNS5 Gas Ignitor
TNS6 Gas Ignitor Power Transformer
HTC High Temperature Cutout
RTRM ReliaTel Refrigeration Module
RHV Reheat Valve
SSP Space Temperature Set Point (Dial)
ODA Outdoor Air Damper Actuator
RDA Return Air Damper Actuator
R 24VAC Power - Terminal R (RTRM)
G Indoor Fan Motor – Terminal G (RTRM)
Y1 Cooling Stage 1 – Terminal Y1 (RTRM)
Y2 Cooling Stage 2 – Terminal Y2 (RTRM)
LTB Low Voltage Terminal Block
RRUTS Control Terminal Strip (Field Connections)
Relays
R1 ODR / RDR (O/Air & R/Air Damper Actuator)
R2 IDM (Indoor Fan Motor)
R3 COOL 1 (Cooling – Stage 1)
R4 COOL 2 (Cooling – Stage 2)
R5 HGRH (Hot Gas Reheat Valve)
R6 HEAT (Heat Relay)
R7 PV (Gas Valve & Gas Ignitor)
R8 MV (Gas Ignitor Disconnect)
R9 ESR (Emergency Stop Relay)
Sensors
OTS Outdoor Air Temperature (OAT)
STS Supply Air Temperature (SAT)
STC Space Temperature (ST)
ORH Outdoor Humidity (ORH)
SHC Space Humidity (SRH)
Operator Set Points
CSP Y1 – O/Air Cooling Enable
OES1 Y1 – O/Air Dehumid Enable
OES2 Y2 – O/Air Dehumid Enable
HESP O/Air Heating Enable
HSP Occupied S/Air Heating
MHSP Minimum Supply Air Heating
SLC S/Air Low Cutoff (Time)
SLT S/Air Low Cutoff (Temperature)
SHC S/Air High Cutoff (Time)
SHT S/Air High Cutoff (Temperature)
Optional—Requires Hot Gas Reheat
(HGRH)
HGRHD HGRH Control Dead Band
RRU-SVX01F-EN
Optional—Requires Space Temperature &
RH Sensors
OSSP Occupied Space Cooling
OSHO Occupied Space Heating Offset
OSRS Occupied Space Humidity
NHSP Unoccupied Space Heating
NCSP Unoccupied Space Cooling
NRSP Unoccupied Space Humidity
NSAS Unoccupied S/Air Heating
Power On—Control Input
"Occupied"
Three Phase Unit Disconnect ON
RRUCM and RTRM Initialize
Control Input Contact CLOSED at RRUTS – 7 & 8
"Occupied" Ventilation Mode
RRUCM Energizes the O/Air Damper Actuator (ODA)
through ODR / RDR Relay R1
O/Air Damper OPENS
R/Air Damper (Optional) CLOSES through ODR / RDR
Relay R1
O/Air Damper makes the Outdoor Damper End Switch
(DES)
RRUCM Energizes the Indoor Fan Motor (IDM) through
IDM Relay R2
R2 Energizes RTRM Terminal G and IDM STARTS
Fan Failure Switch (FFS) Proves Airflow
VENTILATION MODE Established
"Occupied" Conditioning Modes
Outdoor Air Temperature (OTS) and Outdoor Air Relative
Humidity (ORH) sensors located in the Outdoor Air Inlet
controls call for the following operational modes based on
Outdoor Air conditions.
COOLING MODE
Compressor 1 ON
DEHUMIDIFICATION MODE
Compressor 1 or Compressor 1 & 2 ON
HOT GAS REHEAT (OPTIONAL)
Compressor 1 or Compressor 1 & 2 ON
HEATING MODE
Modulating Heat
"Occupied" Cooling Mode
Call for cooling is based on Outdoor Air Temperature
(OAT) sensed at the Outdoor Air Temperature Sensor
(OTS). Y1 – O/Air Cooling Enable Set Point (CSP) is
operator adjustable between 68 F and 80°F.
19