Easy 3L Power Block logs are recording a temperature out-of-tolerance alarm or over temperature

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Issue:
During normal operation with a load between 50 to 100% load and due to low fan speed or other causes, it is possible to get the temperature out of tolerance alarms
Environment:
Startup phase, FSR testing UPS with load, HVAC design and implementation, Break Fix, Temperature alarms activated in the UPS or UPS room. Normal operating status with loads. Loads from 40% to 100%, typically 50% to 75% if the fan speed is low.
Possible Cause:

The power block inverter heatsink temperature is out of tolerance
The power block PFC heatsink temperature is out of tolerance
The temperature sensor could be faulty inside the power block.

These alarms can be pre-activated for the following reasons or a combination of reasons:

The UPS has two ambient temperature sensors. The first is installed on the back of the front panel, and the second is installed on the bypass block control board as a backup.
If the temperature is over 35℃, the ambient temperature sensors monitor the ambient temperature and control the cooling fan's speed.
The placement of the HVAC system and back pressure affect the UPS fans' ability to pull air from the front.

Resolution:

Check for airflow restrictions in front of each power block.
Verify all fans are working and pushing air toward the Power Blocks.
As a contributing factor, check the room's ambient temperature and load percentage.
Verify the HVAC room's back pressure condition as the main contributor or as an additional contributor.
Check the UPS exhaust sections for restrictions and turbulent airflow.

Caution: If the ambient temperature in the UPS room crosses 40°C, the UPS load will shift to bypass operation.

Note: If the above conditions meet, then an FSR visit is required to check the UPS parameters and Event logs. Please contact Schneider Electric.