Liebert TM-10098 service manual Reheating during Dehumidification

iCOM Control Training and Service Manual

When the return air humidity level decreases to 52%RH or 50% of the dehumidification control band the second dehumidification stage is deactivated. When the return air humidity level decreases to the humidity set point of 50% or 0% of the humidity proportional band the first dehumidification stage is deactivated.

2 Stage Compressorized Dehumidification – With Dead Band

Humidity Set Point + (1/2 Dead Band +1/2 Proportional Band)
Humid Set Point: 50%
Proportional Band: 8%					Dehumid
Dead Band: 2%			Dehumid
			Stage 1 On		Stage 2 On
50	51	52	53	54	55
	DB		Dehumid
	Dehumid		Stage 2 Off
	Stage 1 Off		Increasing Humidity

Note: in the above example that the control band begins at the 50% humidity set point and has a length of 5%, which is ½ of the programmed dead band value plus ½ of the programmed humidity proportional band value.

As the return air humidity level increases, first stage dehumidification operation is activated at 53%RH or ½ of the programmed dead band value plus 50% of the dehumidification control band. If the return air humidity level continues to increase the second dehumidification stage actives at 54%RH or ½ of the programmed dead value plus 100% of the programmed humidity proportional control band.

When the return air humidity level decreases to 53%RH or ½ of the programmed dead band value plus 50% of the programmed proportional control band the second dehumidification stage is deactivated. When the return humidity level decreases to 51%RH or ½ of the dead band value plus 0% of the programmed proportional control band the first stage dehumidification deactivated.

Reheating during Dehumidification

The Parameter Electric Reheat Enabled defines how the reheats react when the return air temperature decreases below the temperature set point during the

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