High relative humidity

[Anonymous user]

I have a situation in a data center, We are using 4 InrowRC units, each rack has one Temp & a Temp Humidity sensor, the temperature shows 21c, the RH shows 70%, how to reduce the humidity?

There is a small whole under the raised floor for flood water outlet, in case of any leakage.

Regards

Riyal

[BillP]

Hi,

High Relative Humidity (RH) due to "Dew Point" (DP)and "Ambient Temperature" - mean your Rack Inlet temperature.
With them same dew point, if you have higher Rack Inlet you will have lower Relative Humidity..
(please chekc this link)
http://home.comcast.net/~herbwx/calculat.html#sec3

With the Cooling Unit, almost your DP Temp ~ Coil Temperature.

With InRow RC, quite hard to reduce the RH but you can try :
1. Change the Cooling setpoint higher (so Rack Inlet ~22oC)
2. Set the Supply Air lower and the Fan Speed on manual mode with Low Speed Ref and gain the heat load or reduce number of unit operation. (You will have the natural Reheat system ).
==> You will see RH's fast dropping.
3. Seal your room due to humidity outside come back. If not the humidity will increase faster when the unit stop (due to DP change to higher when unit stop).

[Erasmus_apc · Accepted solution]

I'm not a cooling and humidity person, but have you verified that this measurement is correct? Or, at least, fairly close to being correct based on the sensor placement? I can't tell if you are asking how to fix the issue from the standpoint of "the sensor is wrong", or if you mean you really need to lower the humidity in the room.