Use ACRD200s as backup

[Anonymous user]

We recently moved three ACRD200 (fluid cooled) units to a new data center that already has a cooling system. They are configured as a group, InRow mode. In our old data center, they were the primary cooling. In the new data center we'd like them to act as backups for when the primary cooling system fails. The primary system already keeps the room fairly cold (~72F without any trouble).

I have not been able to configure the setpoints so that the units do not run. Despite the cool setpoint being as high as 80-85, the units still cycle off and on. Are there any tips/tricks to accomplish this? I am aware of the risks of not running these units at all so we have a process in place to ensure they run once a week. Thanks!

[BillP · Accepted solution]

Tony,

Depending on which configuration type the units are set to, they will look at different temperatures to determine if cooling is needed.

Without knowing the exact layout/configuration, the best suggestion I can make is this.

Under Configure Group, set the units into Spot mode, with capacity control set to Discrete.  Then, set you cool setpoint to 78.8°F (the highest allowable), and set the Deadband to 10.0°F.  In this configuration, the units should not come on until the return air temperature reaches 88.8°F (your setpoint, plus your deadband).  The unit(s) will then continue to cool until the return air temperature gets down to 68.8°F (or, your cool setpoint, minus your deadband). 

This setting should, in most cases, allow the units to only come on during a failure of the primary cooling.

If you need further assistance, or want to discuss other configuration options, the best way to reach cooling technical support is calling in to 888-695-6500 and selecting the appropriate options.