It is not uncommon to have a Symbio condenser paired with a blower/fan coil unit w/ a CSTI board. In this application, the customer thermostat (or BAS using dry contacts) will interface with the CSTI through TB3 (see wiring diagram in blower/fan coil) and the CSTI will command the cooling on/off through CSTI J6-5 & J6-7. This is a powered or "wet" output so the use of a pilot relay is necessary to avoid mixing the 24vac from the blower/fan coil unit with the 24vac from the condenser.
Single Stage TTA (Cooling Only)
At this time, CSTI does not support 2 stage DX or heat pump. This article will be updated if this changes.
Be aware that if using test mode on the Symbio controller, that the indoor fan must be running prior to starting test mode.
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.