Troubleshooting
VVT Bypass Controller
Carrier Proprietary and Confidential
CARRIER CORPORATION ©2017
Installation and Start-up Guide
All rights reserved
26
To replace the controller's battery
If the VVT Bypass Controller experiences a power outage and the control program stops functioning, replace
the battery.
You need to replace the battery if the voltage measures below 2.9 volts when the controller is not powered.
1
Verify that the VVT Bypass Controller's power is on.
CAUTION
If the controller's power is not
on
when replacing the battery, your date, time, and trend
data will be lost.
2
Remove the VVT Bypass Controller's cover.
3
Remove the battery from the controller, making note of the battery's polarity.
4
Insert the new battery, matching the battery's polarity with the polarity indicated on the controller's cover.
5
Replace the VVT Bypass Controller's cover.
6
Download the VVT Bypass Controller.
To clean the airflow sensor orifice and replace the filter
In less than .02% of installations, small particulates (micron/submicron-level) can build up in the airflow
sensor's internal orifice or clog the airflow filter, causing airflow restriction. Symptoms of airflow restriction
are:
•
Diffuser noise increases over time
•
Space overcools at minimum airflow
•
Frequency of dampers opening to maintain flow setpoint increases over time
•
AHU fan speed increases over time
To check for these symptoms, set up trending of:
•
Damper position to look for long term increase
•
AHU fan speed for maintaining static pressure
If you see these symptoms, you should clean the flow sensor and replace the filter.