Precedent and Voyager II SZVAV E-Flex with Conventional Thermostat interface
SZVAV E-Flex was never designed to work with or support operation with a Conventional Thermostat application
Recommended to use a zone sensor.
SZVAV operation was released in 2012 with RTRM v13.
The conventional thermostat interface works fine with CV units.
Using a Conventional Thermostat with SZVAV E-Flex, the enhanced functions of the SZVAV and E-Flex operation will be lost if you don't use a Space Temperature sensor.
A couple of options if you want to use the conventional thermostat would be:
- Remove SZVAV configuration and put the unit back to normal CV control. If this is a Precedent unit with a Plenum fan, going this route would allow for 2-step fan control based on the thermostat input request
- Use Zone Sensor Interface or BAS to provide a space temperature and setpoint to the unit, and allow the unit to perform its normal SZVAV functionality.
So while it can do some basic control for your unit, the enhanced capabilities designed into the unit will be greatly degraded. We have seen sites experience humidity issues because of this. So even though you have the choice to use it, we would not recommend it.
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.