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A2L Pairing B Wiring and Setup: Symbio Condenser or Heat Pump with SZVAV / 2 Speed Air Handler with R-454B

Equipment

Condenser: Odyssey A2L Condenser with Symbio 700 Controls

AHU: Odyssey A2L AHU with Symbio control boards and model number digit 15 = D

 

Field Wiring

A2L Symbio Condenser or Heat Pump with SZVAV / 2 Speed Air Handler with R454B

 

💡 Note: Look at the bottom of the link for a downloadable copy of this article.

 

Symbio 700 Quick Links

 

How many wires do I need? 

1 - Up to 7 conductor thermostat wire between the thermostat OR zone sensor and condenser

1 - Up to 6 conductor control wire between the AHU and condenser

2 - 2-conductor twisted, shielded, stranded communication wires between the AHU and condenser. 

 

Cable Identification

 

 

AHU Wiring to Condenser
Cable #1 Modbus Communication

Cable #1 is a Modbus communication link between Symbio 700 and the AHU VFD. It is required for Pairing B as the AHU uses a communicating VFD. This cable must be a 2-conductor, twisted, shielded, stranded cable intended for 2 wire communications. We recommend Trane Purple Comm wire (Windy City Wire Spec #0523003) or any 2 conductor comm wire. 3 Conductor comm wire is also acceptable for Cable #1.  Symbio Communication Wire

 

***DO NOT USE THERMOSTAT, ETHERNET OR NON-COMMUINCATION RATED WIRE FOR COMMUNICATIONS***

 

AHU Wiring to Condenser
Cable #2 Control Wiring

 

AHU Wiring to Condenser
Cable #3 IMC Communications

Cable #3 is an IMC communication link between Symbio 700 and the Indoor Option Module. It is required for electric heat operation and VVZT configuration. This cable must be a 2-conductor, twisted, shielded, stranded cable intended for 2 wire communications. We recommend Trane Purple Comm wire (Windy City Wire Spec #0523003) or any 2 conductor comm wire.  Symbio Communication Wire

***DO NOT USE THERMOSTAT, ETHERNET OR NON-COMMUINCATION RATED WIRE FOR COMMUNICATIONS***

 

Wiring Thermostat to Condenser
Cable #4A Thermostat Wiring

Cable #4A is for conventional thermostat use or when the condenser is controlled by relays. Unit will only use Cable #4A or 4B, not both. 

 

Wiring Zone Sensor to Condenser
Cable #4B Thermostat Wiring

Cable #4B is for zone sensor use and required when VVZT (SZVAV) operation is desired. Zone sensors are commonly used with BAS or can be standalone. Unit will only use Cable #4A or 4B, not both.

*Zone sensor wiring shown for BAYSENS135, other mechanical zone sensors similar. 

 

Emergency Stop Wiring 
From Stop Devices to Symbio 700

 

The wiring above reflects normally closed safeties. Typically, condensate overflow switches (or pan switches) are normally closed devices. If using normally open devices, they can be wired in parallel, and the Customer Connection Polarity does not need to be changed.

For more information see the links below:

 

Configuring the Symbio 700

Odyssey condensers can be paired with many different Odyssey AHUs, 3rd party AHUs and indoor coil assemblies. Due to this, Symbio 700 must be configured for the connected AHU, installed accessories, and controlling sensor/thermostat.

 

Here is an article on accessing and editing the Configuration through the Mobile Phone App:

Symbio™ 700 - Precedent or Odyssey - How to configure or edit configurations using the Mobile Phone App

 

 

For Variable Volume Zone Temperature (VVZT or formerly known as SZVAV) operation, set the configuration as follows:

  • System Type = VVZT (requires zone sensor for actual VVZT operation, conventional thermostat will operate as CVZT)
  • Efficiency = Standard B
  • Indoor Fan Type = Variable Speed (should set automatically)
  • Space Controller = Conventional Thermostat, Single Setpoint Zone sensor, or Dual Setpoint Zone Sensor (zone sensor will use DAT logic for compressor staging)
  • Frostat = Installed (should install automatically)
  • Discharge Temperature Sensor = Installed (should install automatically)
  • Field installed electric heat only
    • TTA condenser
      • Primary Heating Source = Electric
      • Primary Heating Stages = 1 or 2 (depending on electric heat kit stages)
    • TWA condenser
      • Secondary Heating Source = Electric
      • Secondary Heating Stages = 1 or 2 (depending on electric heat kit stages)

 

For Multispeed fan operation, set the configuration as follows:

  • System Type = CVZT (thermostat or zone sensor)
  • Efficiency = Standard B
  • Indoor Fan Type = Multi Speed
  • Space Controller = Conventional Thermostat, Single Setpoint Zone sensor, or Dual Setpoint Zone Sensor
  • Frostat = Installed
  • Discharge Temperature Sensor = Installed (Not required for operation, but it is already installed in the air handler. Zone Sensor will use DAT logic for compressor staging) or Not Installed
  • Field installed electric heat only
    • TTA condenser
      • Primary Heating Source = Electric
      • Primary Heating Stages = 1 or 2 (depending on electric heat kit stages)
    • TWA condenser
      • Secondary Heating Source = Electric
      • Secondary Heating Stages = 1 or 2 (depending on electric heat kit stages)

 

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.

 

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