AirHumidifiers 01 2015 V2

with single heating coil

DV Air handling unit

DV Air handling unit with single heating coil

The performance control can be achieved by an ON-OFF

hygrostat acting on the pump motor contactor.

The evaporative process into the Mollier chart

The illustration on page 5 shows an example of the usual

design process for humidification into the Mollier chart:

Starting from outside air at -3 ºC and 40% RH to achieve

air at 22 ºC and 50% RH.

Single heating coil + humidification

See illustration with 1-2-3 on page 5.

This example has absolute humidity increase

from 1.5 g/kg to 8 g/kg.

With a single heating coil you will need to heat up the air

to a high starting temperature before the humidification.

This will allow you to end up with the desired air condi-

tions.

1. The air is heated up from -3

C and 40% RH through

the rotary heat exchanger and furthermore through the

heating coil until the desired temperature is reached.

Now the air has a RH of 3% and a temperature of 40 °C.

As the air passes through the humidifier, the saturated

pads of the humidifier pass on the moisture to the air.

This changes both the humidity of the air as well as the

temperature.

3. Ending with 22 °C and 50% RH by following the

enthalpy lines in the Mollier chart.

How to choose in SystemairCAD

When choosing the design with one heating coil, it can be

difficult to reach 100% accurate end temperature and

humidity. If this is the chosen solution you may have to

change the CelPad thickness of the HU-CELL material. This

will always be a balance of choosing the correct

humidifier thickness and the correct starting temperature

before humidification. The selection can be made in the

SystemairCAD and calculated instantly to find the leaving

air conditions of the AHU.

| Air Humidifiers