Installation, Operation, and Maintenance Packaged Rooftop Air Conditioners Precedent Gas

48 Pages·2015·6.47 MB·English

Installation, Operation,
and Maintenance
Packaged Rooftop Air Conditioners
Precedent™—Gas/Electric
5 to 10 Tons—50 Hz
SAFETY WARNING
Only qualified personnel should install and service the equipment. The installation, starting up, and servicing
of heating, ventilating, and air-conditioning equipment can be hazardous and requires specific knowledge and
training. Improperly installed, adjusted or altered equipment by an unqualified person could result in death or
serious injury. When working on the equipment, observe all precautions in the literature and on the tags,
stickers, and labels that are attached to the equipment.
March 2015 RT-SVX38C-EN
Introduction
Read this manual thoroughly before operating or servicing
this unit. WARNING
Proper Field Wiring and Grounding
Warnings, Cautions, and Notices
Required!
Safety advisories appear throughout this manual as Failure to follow code could result in death or serious
required. Your personal safety and the proper operation of injury. All field wiring MUST be performed by qualified
this machine depend upon the strict observance of these personnel. Improperly installed and grounded field
precautions. wiring poses FIRE and ELECTROCUTION hazards. To
avoid these hazards, you MUST follow requirements for
field wiring installation and grounding as described in
The three types of advisories are defined as follows: NEC and your local/state electrical codes.
Indicates a potentially hazardous
WARNING WARNING
situation which, if not avoided, could
result in death or serious injury. Personal Protective Equipment (PPE)
CAUTIONs Indicates a potentially hazardous Required!
situation which, if not avoided, could
result in minor or moderate injury. It Installing/servicing this unit could result in exposure to
could also be used to alert against electrical, mechanical and chemical hazards.
unsafe practices. • Before installing/servicing this unit, technicians
NOTICE: Indicates a situation that could result in MUST put on all PPE required for the work being
equipment or property-damage only undertaken (Examples: cut resistant gloves/sleeves,
accidents. butyl gloves, safety glasses, hard hat/bump cap, fall
protection, electrical PPE and arc flash clothing).
Important Environmental Concerns ALWAYS refer to appropriate Material Safety Data
Sheets (MSDS)/Safety Data Sheets (SDS) and OSHA
Scientific research has shown that certain man-made
guidelines for proper PPE.
chemicals can affect the earth’s naturally occurring
stratospheric ozone layer when released to the • When working with or around hazardous chemicals,
atmosphere. In particular, several of the identified ALWAYS refer to the appropriate MSDS/SDS and
chemicals that may affect the ozone layer are refrigerants OSHA/GHS (Global Harmonized System of
that contain Chlorine, Fluorine and Carbon (CFCs) and Classification and Labelling of Chemicals) guidelines
those containing Hydrogen, Chlorine, Fluorine and for information on allowable personal exposure
Carbon (HCFCs). Not all refrigerants containing these levels, proper respiratory protection and handling
compounds have the same potential impact to the instructions.
environment. Trane advocates the responsible handling of • If there is a risk of energized electrical contact, arc, or
all refrigerants-including industry replacements for CFCs flash, technicians MUST put on all PPE in accordance
such as HCFCs and HFCs. with OSHA, NFPA 70E, or other country-specific
requirements for arc flash protection, PRIOR to
Important Responsible Refrigerant
servicing the unit. NEVER PERFORM ANY
Practices SWITCHING, DISCONNECTING, OR VOLTAGE
Trane believes that responsible refrigerant practices are TESTING WITHOUT PROPER ELECTRICAL PPE AND
important to the environment, our customers, and the air ARC FLASH CLOTHING. ENSURE ELECTRICAL
conditioning industry. All technicians who handle METERS AND EQUIPMENT ARE PROPERLY RATED
refrigerants must be certified. The Federal Clean Air Act FOR INTENDED VOLTAGE.
(Section 608) sets forth the requirements for handling, Failure to follow instructions could result in death or
reclaiming, recovering and recycling of certain serious injury.
refrigerants and the equipment that is used in these
service procedures. In addition, some states or
municipalities may have additional requirements that
must also be adhered to for responsible management of
refrigerants. Know the applicable laws and follow them.
© 2015 Trane All rights reserved RT-SVX38C-EN
Introduction
Copyright
This document and the information in it are the property of
Trane, and may not be used or reproduced in whole or in
part without written permission. Trane reserves the right
to revise this publication at any time, and to make changes
to its content without obligation to notify any person of
such revision or change.
Trademarks
All trademarks referenced in this document are the
trademarks of their respective owners.
Revision History
RT-SVX38C-EN (15 March 2015)
• General data 6 to 10 ton updates
RT-SVX38C-EN 3
Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . .38
Warnings, Cautions, and Notices . . . . . . . . 2 ReliaTel™ Control . . . . . . . . . . . . . . . . . . . . .38
Copyright . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 System Status Checkout Procedure . . . . . .38
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . 4 Zone Temperature Sensor (ZTS) Service Indi-
cator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Model Number Description . . . . . . . . . . . . . . 5
Clogged Filter Switch . . . . . . . . . . . . . . . . . .40
General Information . . . . . . . . . . . . . . . . . . . . . 6
Fan Failure Switch . . . . . . . . . . . . . . . . . . . . .40
Unit Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 10
Condensate Overflow Switch . . . . . . . . . . .40
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Zone Temperature Sensor (ZTS) Test . . . .40
Pre-Installation . . . . . . . . . . . . . . . . . . . . . . . 16
Unit Economizer Control (ECA) Troubleshoot-
Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Foundation . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Resetting Cooling and Ignition Lockouts . .42
Ductwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Unit Wiring Diagrams Numbers . . . . . . . . . . .43
Roof Curb . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . .44
General Unit Requirements . . . . . . . . . . . . 19 Combination Gas Electric Air Conditioner .44
Horizontal Discharge Conversion (5 Ton Units) Combination Gas Electric Air Conditioner .44
20
Horizontal Discharge Conversion (6 to 10 Ton
Units) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Requirements for Gas Heat . . . . . . . . . . . . 22
Condensate Drain Configuration . . . . . . . . 22
Filter Installation . . . . . . . . . . . . . . . . . . . . . . 23
Field-Installed Power Wiring . . . . . . . . . . . 23
Main Unit Power . . . . . . . . . . . . . . . . . . . . . 23
Space Temperature Averaging (ReliaTel™ On-
ly) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Pre-Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Voltage Imbalance . . . . . . . . . . . . . . . . . . . . 29
Electrical Phasing (Three-Phase Motors) . 29
Test Modes . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Unit Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Verifying Proper Air Flow . . . . . . . . . . . . . . 32
Economizer Start-Up . . . . . . . . . . . . . . . . . . 32
Compressor Start-Up . . . . . . . . . . . . . . . . . 33
Final System Setup . . . . . . . . . . . . . . . . . . . 33
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Fan Belt Adjustment—Belt Drive Units . . 34
Monthly Maintenance . . . . . . . . . . . . . . . . . 34
Annual Maintenance . . . . . . . . . . . . . . . . . . 36
Final Process . . . . . . . . . . . . . . . . . . . . . . . . . 37
4 RT-SVX38C-EN
Model Number Description
Y S C 0 6 0 E 3 R L A * *
1 2 3 4 5 6 7 8 9 10 11 12 13
Digit 1—Unit Type Digit 16—Hinged Service 7 Clogged filter switch, fan failure
T DX cooling Access/Filters switch and discharge air sensing
Y DX cooling, gas heat 0 Standard panels/standard filters tube
W Packaged heat pump A Hinged access panels/standard A Condensate drain pan overflow
switch
Digit 2—Efficiency filters B Clogged filter switch and condensate
B Standard panels/2" MERV 8 filters
S Standard Efficiency drain pan overflow switch
C Hinged access panels/2" MERV 8
C Fan failure switch and condensate
Digit 3—Airflow filters drain pan overflow switch
C Convertible D Standard panels/2" MERV 13 filters D Discharge air sensing and
E Hinged access panels/2" MERV 13
Digit 4,5,6—Nominal Gross filters condensate drain pan overflow
switch
Cooling Capacity (MBh)
Digit 17—Condenser Coil E Clogged filter switch, fan failure
060 5 ton (17.6 kW) Protection switch and condensate drain pan
072 6 ton (21.1 kW) overflow switch
090 7½ ton (26.4 kW) 0 Standard coil F Clogged filter switch, discharge air
102 8½ ton (29.9 kW) 1 Standard coil with hail guard sensing tube and condensate drain
120 10 ton (35.1 kW) 2 Black epoxy pre-coated condenser pan overflow switch
coil
Digit 7—Major Design Sequence 3 Black epoxy pre-coated G Fan failure switch, discharge air
sensing tube and condensate drain
E R-410A refrigerant
4 ComndpelnetseeCr ocaoti™l w citohn hdaeinl sgeura crodil9 pan overflow switch
Digit 8—Voltage Selection 5 CompleteCoat™ condenser coil with H Clogged filter switch, fan failure
D 380-415/50/3 hail guard9 switch, discharge air sensing and
condensate drain pan overflow
Digit 9—Unit Controls Digit 18—Through the Base switch
R ReliaTel™ microprocessor Provisions Digit 26—System Monitoring
K European 0 No through-the-base provisions
Controls
Digit 10—Heating Capacity Digit 19—Disconnect/Circuit 0 No monitoring controls
0 No electric heat7 Breaker (three-phase only) A Demand control ventilation (CO2)10
L Low heat8
H High heat8 0 No disconnect/no circuit breaker Digit 27—Unit Hardware
Digit 20—Convenience Outlet Enhancements
Digit 11—Minor Design
Sequence 0 No convenience outlet 01 SNtoa iennlehsasn scteemele dnrtasin pan
A First sequence Digit 21—Communications
Model Number Notes
Options
Digit 12,13—Service Sequence
0 No communications interface 1. Manual outside air damper will ship
** Factory assigned
1 Trane communications interface factory supplied within the unit, but
Digit 14—Fresh Air Selection 2 LonTalk® communications interface must be field installed.
0 No Fresh air Digit 22—Refrigeration System 2. High pressure control crankcase
A Manual outside air damper 0–50%1
Option heaters are standard on all units.
B Motorized Outside air damper 0–50%
C Economizer, dry bulb 0–100% 0 Standard refrigeration system5 3. Belt drive is standard on all units.
without barometric relief4 Digit 23—Refrigeration Controls 4. Economizer with barometric relief is
D Economizer, dry bulb 0–100% with for downflow configured units only.
E Ebcaoronmometirziecr ,r erelifeefr4ence enthalpy N0 otNe:o rAepfrpigliecraabtlieo nto c odnigtirto 7l2 = E Order economizer without barometric
0-100% without barometric relief3,4 1 Frostat™6 relief for horizontal configuration.
Barometric relief for horizontal
F E
0-c1o0n0o%m wizietrh, rbeafreormenecteri ce nrethliaelfp3y,4 Digit 24—Smoke Detector configured units must be ordered as
G Economizer, comparative enthalpy 0 No smoke detector field-installed accessory.
0–100% without barometric relief3,4 Digit 25—System Monitoring 5. Standard metering devices are TXVs.
H
0E–c1o0n0o%m wizeitrh, cboamropmareatrticv er eelnietfh3a,4lpy Controls 6. Frostat is available as
0 No monitoring control factory-installed option only.
Digit 15—Supply Fan/Drive Type/ 1 Clogged filter switch
7. Electric heaters are available only for
Motor 2 Fan failure switch
0 Standard drive3 3 Discharge air sensing tube field-installed options.
1 Oversized motor 4 Clogged filter switch and fan failure 8. Available only for gas heat models.
switch
9. Not available on heat pumps.
5 Clogged filter switch and discharge
air sensing tube 10. Demand control ventilation option
6 Fan failure switch and discharge air includes wiring only. The C02 sensor
sensing tube is a field-installed only option.
RT-SVX38C-EN 5
General Information
Unit Inspection Compressor Nameplate
As soon as the unit arrives at the job site The nameplate for the compressors are located on the side
of the compressor.
• Verify that the nameplate data matches the data on the
sales order and bill of lading (including electrical data).
Unit Description
• Verify that the power supply complies with the unit
Before shipment, each unit is leak tested, dehydrated,
nameplate specifications.
charged with refrigerant and compressor oil, and run
• Visually inspect the exterior of the unit, including the tested for proper control operation.
roof, for signs of shipping damage.
The condenser coils are either aluminum fin, mechanically
If the job site inspection of the unit reveals damage or bonded to copper tubing or all aluminum microchannel.
material shortages, file a claim with the carrier
Direct-drive, vertical discharge condenser fans are
immediately. Specify the type and extent of the damage on
provided with built-in thermal overload protection.
the “bill of lading” before signing.
There are two control systems offered for these units. The
• Visually inspect the internal components for shipping
electromechanical control option uses a thermostat to
damage as soon as possible after delivery and before
perform unit functions. The ReliaTel™ control module is a
it is stored. Do not walk on the sheet metal base pans.
microelectronic control system that is referred to as
• If concealed damage is discovered, notify the carrier’s “refrigeration module” (RTRM). The acronym RTRM is
terminal of damage immediately by phone and by used extensively throughout this document when
mail. Concealed damage must be reported within 15 referring to the control system network.
days.
These modules through proportional/integral control
• Request an immediate joint inspection of the damage algorithms perform specific unit functions that govern unit
by the carrier and the consignee. Do not remove operation in response to zone temperature, supply air
damaged material from the receiving location. Take temperature, and/or humidity conditions depending on
photos of the damage, if possible. The owner must the application. The stages of capacity control for these
provide reasonable evidence that the damage did not units are achieved by starting and stopping the
occur after delivery. compressors.
• Notify the appropriate sales representative before The RTRM is mounted in the control panel and is factory
installing or repairing a damaged unit. wired to the respective internal components. The RTRM
receives and interprets information from other unit
Storage
modules, sensors, remote panels, and customer binary
Take precautions to prevent condensate from forming contacts to satisfy the applicable request for cooling.
inside the unit’s electrical compartments and motors in the
following situations: Economizer Control Actuator (Optional)
• The unit is stored before it is installed. ReliaTel™ Control
• The unit is set on the roof curb, and temporary heat is The ECA monitors the mixed air temperature, return air
provided in the building. Isolate all side panel service temperature, minimum position setpoint (local or
entrances and base pan openings (e.g., conduit holes, remote), power exhaust setpoint, CO2 setpoint, CO2, and
Supply Air and Return Air openings, and flue ambient dry bulb/enthalpy sensor or comparative
openings) from the ambient air until the unit is ready humidity (return air humidity against ambient humidity)
for start-up. sensors, if selected, to control dampers to an accuracy of
Note: Do not use the unit’s heater for temporary heat +/- 5% of stroke. The actuator is spring returned to the
without first completing the start-up procedure closed position any time that power is lost to the unit. It is
detailed under “Unit Start-Up,” p. 32. capable of delivering up to 25 inch pounds of torque and
is powered by 24 VAC.
The manufacturer will not assume any responsibility for
equipment damage resulting from condensate RTCI—ReliaTel™ Trane Communication
accumulation on the unit’s electrical and/or mechanical Interface (Optional)
components.
This module is used when the application calls for an
Unit Nameplate ICSTM building management type control system. It
allows the control and monitoring of the system through
A Mylar unit nameplate is located on the unit’s corner an ICS panel. The module can be ordered from the factory
support next to the filter access panel. It includes the unit or ordered as a kit to be field installed. Follow the
model number, serial number, electrical characteristics,
refrigerant charge, as well as other pertinent unit data.
6 RT-SVX38C-EN
General Information
installation instruction that ships with each kit when field RTOM. A diagnostic SERVICE signal is sent to the remote
installation is necessary. panel if the pressure differential across the filters is at least
0.5" w.c. The contacts will automatically open when the
RLCI—ReliaTel™ LonTalk® Communication
pressure differential across the filters decreases to
Interface (Optional) approximately 0.4" w.c. The clogged filter output is
energized when the supply fan is operating and the
This module is used when the application calls for an
clogged filter switch has been closed for at least 2 minutes.
ICSTM building management type control system that is
The system will continue to operate regardless of the
LonTalk. It allows the control and monitoring of the system
status of the filter switch.
through an ICS panel. The module can be ordered from the
factory or ordered as a kit to be field installed. Follow the Note: On units equipped with factory installed MERV 13
installation instruction that ships with each kit when field filters, a clogged filter switch with different
installation is necessary. pressure settings will be installed. This switch will
close when the differential pressure is
RBCI—ReliaTel™ BACnet™ Communications
approximately 0.8' w.c. and open when the
Interface (Optional)
differential falls to 0.7" w.c.
This module is used when the application calls for an open
Condensate Drain Pan Overflow Switch
BACnet protocol. It allows the control and monitoring of
(Optional)
the system through an ICS panel. The module can be
ordered from the factory or as a kit to be field installed.
ReliaTel Option
Follow the installation instructions that ships with each kit
when field installation is necessary. This input incorporates the Condensate Overflow Switch
(COF) mounted on the drain pan and the ReliaTel options
RTOM—ReliaTel™ Options Module (Optional) module (RTOM). When the condensate level reaches the
trip point for 6 continuous seconds, the RTOM will shut
The RTOM monitors the supply fan proving, clogged filter,
down all unit functions until the overflow condition has
supply air temperature, exhaust fan setpoint, supply air
cleared. The unit will return to normal operation after six
tempering, Frostat™ and smoke detector. Refer to system
continuous seconds with the COF in a non-tripped
input devices and functions for operation.
condition. If the condensate level causes unit shutdown
System Input Devices and Functions more than two times in a 3-day period, the unit will be
locked-out of operation requiring manual reset of
The RTRM must have a zone sensor or thermostat input in
diagnostic system through zone sensor or building
order to operate the unit. The flexibility of having several
automation system (BAS). Cycling unit power will also
mode capabilities depends upon the type of zone sensor or
clear the fault.
thermostat selected to interface with the RTRM.
Compressor Disable (CPR1/2)
The descriptions of the following basic Input Devices used
within the RTRM network are to acquaint the operator with This input incorporates the low pressure control (LPC) of
their function as they interface with the various modules. each refrigeration circuit and can be activated by opening
Refer to the unit’s electrical schematic for the specific a field-supplied contact installed on the LTB.
module connections.
If this circuit is open before the compressor is started, the
The following controls are available from the factory for compressor will not be allowed to operate. Anytime this
field installation. circuit is opened for 1 continuous second during
compressor operation, the compressor for that circuit is
Supply Fan Failure Input (Optional)
immediately turned “Off”. The compressor will not be
The Fan Failure Switch can be connected to sense indoor allowed to restart for a minimum of 3 minutes should the
fan operation: contacts close.
FFS (Fan Failure Switch)—If air flow through the unit is not If four consecutive open conditions occur during the first
proven by the differential pressure switch connected to the three minutes of operation, the compressor for that circuit
RTOM (factory setpoint 0.07" w.c.) within 40 seconds will be locked out, a diagnostic communicated to the
nominally, the RTRM will shut off all mechanical remote panel (if installed), and a manual reset will be
operations, lock the system out, send a diagnostic to ICS, required to restart the compressor.
and the SERVICE output will flash. The system will remain
locked out until a reset is initiated either manually or Low Pressure Control
through ICS.
ReliaTel Control
Clogged Filter Switch (Optional)
When the LPC is opened for 1 continuous second, the
The unit-mounted clogged filter switch monitors the compressor for that circuit is turned off immediately. The
pressure differential across the return air filters. It is compressor will not be allowed to restart for a minimum
mounted in the filter section and is connected to the of 3 minutes.
RT-SVX38C-EN 7
General Information
If four consecutive open conditions occur during an active power is interrupted, the program is retained in
call for cooling, the compressor will be locked out, a permanent memory. If power is off for an extended period
diagnostic communicated to ICS™, if applicable, and a of time, only the clock and day may have to be reset.
manual reset required to restart the compressor. On dual
The Zone Sensor allows selection of 2, 3, or 4 system
compressor units only the affected compressor circuit is
modes (Heat, Cool, Auto, and Off), two fan modes (On and
locked out.
Auto). It has dual temperature selection with
programmable start time capability.
High Pressure Control
The occupied cooling set point ranges between 45ºF and
ReliaTel Control
98ºF. The heating set point ranges between 43ºF and 96ºF.
The high pressure controls are wired in series between the A liquid crystal display (LCD) displays zone temperature,
compressor outputs on the RTRM and the compressor temperature set points, day of the week, time, and
contactor coils. If the high pressure control switch opens, operational mode symbols.
the RTRM senses a lack of current while calling for cooling
The Option Menu is used to enable or disable applicable
and locks the compressor out.
functions, e.g., morning warm-up, economizer minimum
If four consecutive open conditions occur during an active position override during unoccupied status, Fahrenheit or
call for cooling, the compressor will be locked out, a Centigrade, supply air tempering, remote zone
diagnostic communicated to ICS, if applicable, and a temperature sensor, 12/24 hour time display, smart fan,
manual reset required to restart the compressor. On dual and computed recovery.
compressor units only the affected compressor circuit is
During an occupied period, an auxiliary relay rated for 1.25
locked out.
amps at 30 volts AC with one set of single pole double
throw contacts is activated.
Lead/Lag Control (Dual Circuit Only)
ReliaTel Control Only Status Inputs (4 Wires Optional)
The ZSM can be wired to receive four operating status
Lead/Lag is a selectable input located on the RTRM. The
signals from the RTRM (HEAT, COOL, SYSTEM ON,
RTRM is configured from the factory with the Lead/Lag
SERVICE).
control disabled. To activate the Lead/Lag function, simply
cut the wire connected to J3-8 at the RTRM. When it is Four wires from the RTRM should be connected to the
activated, each time the designated lead compressor is appropriate terminals (7, 8, 9, and 10) on the ZSM.
shut off due to the load being satisfied, the lead
Remote Zone Sensor (BAYSENS073*)
compressor or refrigeration circuit switches. When the
RTRM is powered up,e.g., after a power failure, the control This electronic sensor features remote zone sensing and
will default to the number one circuit compressor. timed override with override cancellation. It is used with a
Trane Integrated Comfort™ building management
Zone Sensor Module (ZSM) (BAYSENS106*)
system.
This electronic sensor features three system switch
Remote Zone Sensor (BAYSENS074*)
settings (Heat, Cool, and Off) and two fan settings (On and
Auto). It is a manual changeover control with single This electronic sensor features single setpoint capability
setpoint. (Cooling Setpoint Only) and timed override with override cancellation. It is used
with a Trane Integrated Comfort™ building management
Zone Sensor Module (ZSM) (BAYSENS108*)
system.
This electronic sensor features four system switch settings
Remote Zone Sensor (BAYSENS016*)
(Heat, Cool, Auto, and Off) and two fan settings (On and
Auto). It is a manual or auto changeover control with dual This bullet type temperature sensor can be used for
setpoint capability. It can be used with a remote zone outside air (ambient) sensing, return air temperature
temperature sensor BAYSENS077*. sensing, supply air temperature sensing, remote
temperature sensing (uncovered). Wiring procedures vary
Zone Sensor (BAYSENS110*)
according to the particular application and equipment
This electronic sensor features four system switch settings involved. Refer to the unit’s wiring diagrams for proper
(Heat, Cool, Auto, and Off) and two fan settings (On and connections.
Auto) with four system status LEDs. It is a manual or auto
Remote Zone Sensor (BAYSENS077*)
changeover control with dual setpoint capability. It can be
used with a remote zone temperature sensor This electronic sensor can be used with BAYSENS106*,
BAYSENS077*. 108*, 110*, 119* remote panels. When this sensor is wired
to a BAYSENS119* Remote Panel, wiring must be 18 AWG
Programmable Zone Sensor—(BAYSENS119*)
Shielded Twisted Pair (Belden 8760 or equivalent). Refer to
This 7-day programmable sensor features 2, 3, or 4 periods the specific remote panel for wiring details.
for Occupied or Unoccupied programming per day. If the
8 RT-SVX38C-EN
General Information
Wireless Zone Sensor (BAYSENS050)
This electronic sensor features five system settings (Auto,
Off, Cool, Heat, and Emergency Heat) as well as On and
Auto fan settings. It is a manual or auto changeover control
with dual setpoint capability. Other features include a
timed override function, lockable system settings, and
Fahrenheit or Celsius temperature display. Included with
the wireless zone sensor is a receiver that is to be mounted
inside the unit, a mounting bracket, and a wire harness.
High Temperature Sensor (BAYFRST001*)
This sensor connects to the RTRM emergency stop input
on the LTB and provides high limit “shutdown” of the unit.
The sensor is used to detect high temperatures due to a
high thermal event in the air conditioning or ventilation
ducts. The sensor is designed to mount directly to the
sheet metal duct. Each kit contains two sensors. The return
air duct sensor (X1310004001) is set to open at 135ºF. The
supply air duct sensor (X1310004002) is set to open at
240ºF. The control can be reset after the temperature has
been lowered approximately 25ºF below the cutout
setpoint.
Evaporator Frost Control
ReliaTel™ Option
This input incorporates the Frostat™ control (FOS)
mounted in the indoor coil circuit and can be activated by
closing a field-supplied contact installed in parallel with
the FOS.
If this circuit is open before the compressor is started, the
compressor will not be allowed to operate. Anytime this
circuit is opened for 1 continuous second during
compressor operation, the compressor for that circuit
immediately turns off. The compressor will not be allowed
to restart for a minimum of 3 minutes if the FOS closes.
Discharge Line Temp Switch (DLTS)
The DLTS is looped in series with HPC and LPC. It prevents
compressor from overheating (over 300Fº dome temp) in
case of indoor fan failure (cooling) or outdoor fan failure
(heating).
Phase Monitor
This sensor monitors voltage between the 3 conductors of
the 3-phase power supply. Two LED lights are provided:
• The green light indicates that a balanced 3-phase
supply circuit is properly connected.
• The red light indicates that unit operation has been
prevented. There are two conditions that will prevent
unit operation:
• The power supply circuit is not balanced with the
proper phase sequence of L1, L2, L3, for the 3
conductors of a 3-phase circuit.
• The line to line voltage is not between 180 volts and
633 volts.
RT-SVX38C-EN 9
Unit Dimensions
Figure 1 illustrates the minimum operating and service Providing less than the recommended clearances may
clearances for either a single or multiple unit installation. result in condenser coil starvation, “short-circuiting” of
These clearances are the minimum distances necessary to exhaust and economizer airflows, or recirculation of hot
assure adequate serviceability, cataloged unit capacity, condenser air.
and peak operating efficiency.
Figure 1. Typical installation clearances for single and multiple unit applications
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