Compatibility
The BAYSENS800 (Service P/N: X13791009001) is a full-color touchscreen programmable zone sensor designed for standalone HVAC applications using Trane Symbio™ 700 unit controllers.
IMPORTANT COMPATIBILITY RESTRICTIONS
- Incompatible Sensors: The BAYSENS924 is not compatible with the Symbio 700. Only use BAYSENS800 (X13791009001).
- System Types: Supported on Constant Volume Zone Temperature (CVZT) and Variable Volume Zone Temperature (VVZT) systems. It is not compatible with Multiple Zone VAV (MZVAV) or Variable Volume Discharge Air (VVDA) configurations.
- Standalone Operation: BAYSENS800 is intended for standalone unit control. Later hardware revisions (e.g., BAYSENS800AB) may be connected to a Building Automation System (BAS) for monitoring purposes only.
- Dedicated Bus: BAYSENS800 communicates via BACnet MS/TP. If an optional LonTalk® or Air-Fi® wireless adapter is connected to the Symbio 700, it must be disconnected.
Unit Controller License Requirements
The Symbio 700 controller must possess an Advanced License to communicate with the BAYSENS800.
| Item | Details |
|---|---|
| Model Digit Verification | Check Digit 21 of the unit model number (Odyssey™ or Precedent™): • 1 = Advanced License w/ BACnet® MS/TP • 2 = Advanced License w/ LonTalk® (Requires removal for BAYSENS800) • 3 = Advanced License w/ Air-Fi® (Requires removal for BAYSENS800) |
| App Verification | Connect via the Symbio Service & Installation App (v1.0.2 or higher). Navigate to Home > Show More > License Type to confirm Advanced. |
| Upgrade Options | If the controller has a Basic License: 1. Order Software Upgrade: Purchase license upgrade kit FRW00001 via Trane Parts. 2. Replace Controller: Order pre-licensed Advanced Controller MOD04044. |
Symbio Service & Installation App License
Screen displaying License Type: Advanced vs. License Type: Basic.
Wiring
Always disconnect all electrical power sources before making electrical connections to prevent equipment damage or personal injury.
BAYSENS800 Backplate Terminals
┌───┬───┬───┬───┬───┬───┬───┬───┐
│ A │ B │ C │ D │ E │ F │ G │ H │
└───┴───┴───┴───┴───┴───┴───┴───┘
│ │ │ │ │ │ │ │
│ │ │ │ │ │ └───┴── Remote Thermistor / Motion Common
│ │ │ │ │ └────────── Demand Shed Input
│ │ │ │ └────────────── BACnet Reference / Shield Ground
│ │ └───┴────────────────── BACnet MS/TP Comm (+ / -)
└───┴────────────────────────── 24 VAC Power / Ground
| Terminal | Description | Symbio 700 Connection | Wire Specification |
|---|---|---|---|
| A (5) | 24 VAC (Hot) | J19-6 | 18 AWG 2-conductor stranded |
| B (6) | 24 VAC Ground | J19-7 | 18 AWG 2-conductor stranded |
| C (13) | BACnet (+) | J17-1 | 22–18 AWG shielded twisted pair (100–130 Ω impedance) |
| D (14) | BACnet (-) | J17-2 | 22–18 AWG shielded twisted pair (100–130 Ω impedance) |
| E | BACnet Reference (Shield) | Chassis Ground / Earth | Continuous shield tied to ground at one end only |
| F | Demand Shed | External Contact | Low-voltage discrete signal (optional) |
| G | Remote Thermistor / Motion | Remote Sensor Lead 1 | 18 AWG twisted pair (optional) |
| H | Input Common | Remote Sensor Lead 2 | 18 AWG twisted pair (optional) |
Image details: Point-to-point schematic illustrating Terminals A & B routed to Symbio 700 plug J19 (pins 6 & 7) and Terminals C & D routed to plug J17 (pins 1 & 2), with shield grounded at J21-9
Basic Wiring to Symbio 700 (UC)
Option A: Remote Sensor(s) Connected to Symbio 700 (Preferred)
- Land thermistor leads across the designated zone temperature input terminals on the Symbio 700 board (J16).
- In the BAYSENS800 menu, set the temperature source to Remote.
Wiring with Single Remote Sensor (BAYSENS077*) connected to Symbio 700 (UC)
- Image details: Wiring diagram showing a single BAYSENS077 remote sensor connected across Symbio 700 plug J16.
Wiring with Four Remote Sensors (BAYSENS077*) for Sensor Averaging connected to Symbio 700 (UC)
- Image details: Schematic depicting 4 sensors wired in a 2×2 series-parallel network landed onto Symbio 700 plug J16.
Option B: Remote Sensor(s) Connected to BAYSENS800
- Connect thermistor leads to terminals G and H on the back of the BAYSENS800.
- In the BAYSENS800 menu, set UC17 config to Temp and set temperature source to Wired.
Wiring with Single Remote Sensor (BAYSENS077*) connected to the BAYSENS800
- Image details: Wiring schematic showing remote sensor leads connecting directly to BAYSENS800 subbase terminals G and H
Wiring with Four Remote Sensors (BAYSENS077*) for Sensor Averaging connected to the BAYSENS800
- Image details: Schematic depicting 4 sensors wired in a 2×2 series-parallel network connected to BAYSENS800 terminals G and H.
Multi-Sensor Averaging Rules
To maintain the correct 10k Ω Type II thermistor resistance curve, sensor averaging networks must utilize a square number of identical sensors wired in series-parallel:
- 4 Sensors: 2 parallel strings of 2 sensors in series.
- 9 Sensors: 3 parallel strings of 3 sensors in series.
- 16 Sensors: 4 parallel strings of 4 sensors in series.
- 25 Sensors: 5 parallel strings of 5 sensors in series.
For complete schematic wiring diagrams, refer to How to average multiple zone temp sensors.
Recommended Communication Cable
BACnet MS/TP communication requires low-capacitance, shielded twisted pair (STP) cable:
-
Approved Supplier: Windy City Wire
- Plenum-Rated: P/N 043005AL
- Non-Plenum Rated: P/N 108760
-
Alternative Cable Specifications:
- Conductor Gauge: 22 AWG to 18 AWG stranded twisted pair with shield.
- Characteristic Impedance: 100 to 130 Ω.
- Capacitance (Conductor to Conductor): <100 pF/m (<30 pF/ft).
- Capacitance (Conductor to Shield): <200 pF/m (<60 pF/ft).
Configuration
Controller Configuration
Set Physical Rotary Dials
Set the physical rotary address dials on the face of the Symbio 700 module to 001.
Configure via the Symbio Service & Installation Mobile App
- Connect to the Symbio 700 using Bluetooth via the Symbio Service & Installation App.
- Enable External Control:
- Go to Settings > System.
- Set Arbitration Method Request to Enable External BAS Control.
- Settings > System with Arbitration Method Request toggled/set to Enable External BAS Control.
Configure Space Controller:
- Navigate to Settings > View Configuration > Edit.
- Set Space Controller Type to Single Setpoint Zone Sensor.
- Verify that System Type is configured as CVZT or VVZT (VVDA and MZVAV are not supported).
View Configuration > Edit highlighting Space Controller Type = Single Setpoint Zone Sensor.
Configure BACnet Protocol:
- Navigate to Tools > Protocol Configuration > Protocol.
- Select BACnet MS/TP.
- Set the Baud Rate to 76800 bps.
- Tap Save.
- Tools > Protocol Configuration with Protocol set to BACnet MS/TP and Baud Rate set to 76800.
BAYSENS800 On-Screen Configuration
Entering Technician Configuration
- Tap the touchscreen display to wake the sensor.
- Press and hold the lower right corner (or settings icon) for 5 seconds.
- Enter the Technician Passcode: 4017.
Network Setup
Both devices must reside on the same MS/TP network with matching baud rates and unique MAC addresses/Device IDs.
Legacy Firmware (2 Network Configuration Pages)
- Sensor Address (MAC): 2
- Unit Address (MAC): 1
- Baud Rate: 76,800
Image details: Screen capture/photo of legacy firmware Network Pages showing Sensor Address = 2, Unit Address = 1, and Baud Rate = 76,800.
Current Firmware (3 Network Configuration Pages)
-
Network Page 1:
- Sensor Address: 2
- Baud Rate: 76,800
-
Network Page 2:
- Sensor Device ID: 0000002
-
Network Page 3:
- Unit Device ID: 0000001
Image details: Screen capture/photos showing Network Page 1 (Sensor Addr: 2, Baud: 76800), Page 2 (Device ID: 0000002), and Page 3 (Unit Device ID: 0000001).
TIP: Ensure you press the Right Arrow / Next button through all pages to commit and save the parameters to non-volatile memory.
Remote Thermistor Input Setup
If an external thermistor is being utilized instead of the sensor's internal thermistor:
-
When wired to Symbio 700 (Option A):
- Go to Configuration Page 2.
- Set Temp. Sensor to Remote.
-
When wired directly to BAYSENS800 (Option B):
- Go to Configuration Page 2.
- Set UC17 config to Temp.
- Set Temp. Sensor to Wired.
Image details: Display screenshot showing Configuration
Literature Links
- How to average multiple zone temp sensors
- Legacy Firmware BAYSENS800 Manual BAS-SVN028*-EN
- Current Firmware BAYSENS800 Manual BAS-SVP080*-EN
Interactive Troubleshooting
Symbio™ 700 & BAYSENS800
Diagnostic Rules Evaluation
1. Physical Wiring & HW
OKVirtual BAYSENS800 Touchscreen
Installer PIN: 4017Symbio Service & Installation App
How to Enter Configuration Mode
The BAYSENS800 touchscreen provides access to the password-protected installer setup screens through a hidden touch gesture on the home screen:
- Ensure the sensor is powered on and displaying the Home Screen (showing indoor temperature, occupancy, and time).
- Touch and hold the top center location of the display glass for 2 seconds.
-
Release your finger when the display transitions
to the
Installer Passwordkeypad screen.
How to Enter the Password
All installer menus require the factory password:
-
On the
Installer Passwordscreen, use the numeric keypad buttons0through9. - Enter the fixed installer password: 4 0 1 7.
- Once the fourth digit is entered, the sensor automatically validates the passcode and unlocks the 1 / 2 Setup screen.
4017 and cannot be modified in
the field.
How to Configure Network Settings (1/3 Network Settings & Figure 4)
Proper MS/TP token passing requires matching communication parameters between the Symbio 700 controller and BAYSENS800:
- From the 1 / 2 Setup menu, select Network.
-
On 1/3 Network Settings (or 1/2
in legacy firmware), configure:
-
Sens. address: Set to a
unique BACnet MAC address (typically
2on a dedicated sensor link; range 0–127). -
Baud rate: Must match the
Symbio 700 baud rate exactly (default:
76800). -
Status: Displays
onlinewhen valid token frames are detected. If incorrect, it indicatesoffline.
-
Sens. address: Set to a
unique BACnet MAC address (typically
-
In older firmware, set Unit address
to match the rotary dial on the Symbio 700 (typically
1).
2/2 Network Instance / 2/3 Sensor Device ID & The [R] Button
BACnet device instance numbers must be correctly formatted to prevent network conflicts:
- Navigate to 2/2 Network Instance (or 2/3 Sensor Device ID on updated Figure 4 firmware).
-
If the displayed instance shows an unconfigured or
unexpected number:
- Press the [R] button on the touchscreen.
- Touching [R] automatically copies the sensor MAC address number into the BACnet Device ID field, resetting it to 000002 (or 0011002).
- Press the checkmark button (✓) to confirm and save the new instance value.
How to Configure 2/4 Configuration (UC17 & Temp Sensor)
Terminals 17 and 18 can be configured for auxiliary sensing or remote temperature:
- From the 1 / 2 Setup screen, tap Configuration.
- Advance past 1/4 Configuration to page 2/4 Configuration.
-
Set UC17 config:
-
None: Terminals 17 and 18 are not in use (standard installation). -
Motion: Connected to a remote dry contact occupancy/motion sensor. -
Temp: Connected to an external 10k Type 2 thermistor sensor.
-
-
Set Temp. sensor:
-
Internal: Uses the sensor's high-precision on-board thermistor (default). -
Remote: Uses an external sensor wired directly to the HVAC equipment. -
Wired: Uses the external sensor landed on terminals 17 and 18.
-
How to Enter Service View 4/7 & Verify Online Status
Service View allows field technicians to monitor real-time controller telemetry and diagnostics without specialized software:
- From the 1 / 2 Setup screen, select Service View.
- Use the screen advance buttons to scroll to page 4/7 Service View.
-
Inspect the Unit status field:
- Online: Indicates active bidirectional BACnet MS/TP communication with the Symbio 700.
- Offline: Indicates broken communication. Check polarity (J17-1 to C, J17-2 to D), baud mismatch, or address collision.
-
Also verify that the sensor failure diagnostics (
DAT sensor fail,OAT sensor fail, etc.) showOff.
How to Verify Lua 1/3 (Trane_Symbio-v)
The BAYSENS800 uses custom embedded Lua scripts to translate points for specific Trane controllers:
- From the 1 / 2 Setup screen, advance to 2 / 2 Setup.
- Select Lua to enter the firmware verification menu.
- On page 1/3 Lua, verify that the top header reads: Trane_Symbio-v1. :
- Confirm the hardware part number reads X13791009001 (BAYSENS800).
-
Confirm the client description reads:
Network Client for Symbio 800 rev 1.3.8 (based on Trane rev 6.11).
Trane_ReliaTel-V
or Trane_UC400, the sensor is the wrong
model for this unit.
Wiring Needed
The Programmable Zone Sensors only support the BACnet MS/TP communication protocol for integration to either Trane or non-Trane control systems.
Communication Wire
Use the correct communication wire to ensure reliable communication between the zone sensor and the HVAC equipment.
-
Plenum rated P/N:
043005AL -
Non-plenum rated P/N:
108760
Other wire may be used if it conforms with the following physical characteristics:
- Twisted pair (2-conductor) plus shield
- Characteristic impedance: 100–130 ohms
- Distributed capacitance between conductors: <100 pF/m
- Distributed capacitance between conductor and shield: <200 pF/m
- Foil or braided shield is acceptable
- Maximum length (end to end): 4000 ft with 18 AWG conductor wires
- Maximum length (end to end): 2000 ft with 22 AWG conductor wires
Configuring the Unit (Symbio 700)
1. Connect & Enable External Control
- Connect to the Symbio 700 using Bluetooth via the Symbio Service & Installation App.
- Go to Settings > System.
- Set Arbitration Method Request to Enable External BAS Control.
Settings > System with
Arbitration Method Request toggled/set to
Enable External BAS Control.
2. Configure Space Controller
- Navigate to Settings > View Configuration > Edit.
- Set Space Controller Type to Single Setpoint Zone Sensor.
- Verify that System Type is configured as CVZT or VVZT (VVDA and MZVAV are not supported).
View Configuration > Edit highlighting
Space Controller Type = Single Setpoint Zone Sensor.
3. Configure BACnet Protocol
- Navigate to Tools > Protocol Configuration > Protocol.
- Select BACnet MS/TP.
- Set the Baud Rate to 76800 bps.
- Tap Save.
Tools > Protocol Configuration with
Protocol set to BACnet MS/TP
and Baud Rate set to 76800.
Which BAYSENS800 Manual to Use
Two different BAYSENS800 manuals are published, covering two different firmware generations of the sensor. Using the wrong one for the unit in front of you is a common source of confusion during setup and troubleshooting.
If the menu screens or wording on the physical sensor don't match what a manual describes, check the other one — it usually means the sensor is running the other firmware generation.
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.