Soft Water Supply for Humidifiers

Introduction
Using hard water directly from running taps often kills the electronic ultrasonic humidifier. This is because hard water will form scales that will eventually damage the ultrasonic vibrator of the humidifier. This article will describe a method where one can obtain reasonably clean soft water for proper humidifier operation.

What is Hard and Soft Water ?
Water is said to be "hard" when it contains minerals such as calcium carbonates and other derivatives or metal oxides. Hard water usually comes from the ground water that contains a lot of minerals. One can turn hard water into soft water simply by boiling. The other way is to use reverse osmosis machines. But these methods will use a lot of energy. The other method is to find soft water sources. One of the many sources is rain water but it is not clean. Yet another method is to use condensate water.

How Do We Get Condensate Water?
One can get condensate water from cooling the air. When air is cooled to its dew point temperature (around 25 degree C depending on where you live), moisture in the air will condensate into water. One can get this water from a special water making machine.

or simply from any air-conditioning unit. This article will concentrate on how to obtain clean soft water from our normal air conditioning units.

Condensate Water from Air-Conditioner Units

Every air-conditioner unit will have a condensate water piping running from the cooling or evaporating coils to the nearest drain. This water is usually clean except for some dust particulates that are also collected together with the air that passes through the evaporator coil. Dirty water tray and piping can also pollute this water. To get clean condensate water, one must prepare the air-conditioner unit and install a water filter to receive and store the water. To filter and store the water, one can use the common mineral water filter shown as follows:-



Preparing the Air-Conditioner Unit

Every air-conditioner unit has a plastic water tray underneath each evaporator coil. This tray is always connected to a drain pipe. One must always ensure that this tray and the drain pipe are always clean and free from algae forming. One must also change the air filter at least once every month, depending on the usage.  Additional secondary air filter can be added to the evaporator coil for cleaner water to be produced.

Preparing the Mineral Water Filter

Mineral Water Filter (MWF) has a dome shape ceramic filter on top and a plastic cylinder that is filled with various mineral sand and stones.


To ensure the water remain soft, one must remove the cylinder of mineral sand or stones or replace them with silica sand that has no mineral content.

Making Water Overflow and Drain Pipe

One would have to make additional holes in the MWF for inserting overflow pipes in the top plastic container as well as the storage container as shown. The existing drain pipe should be cut and be diverted to fill water into the MWF. The new overflow pipes should be connected to the existing drain pipe as shown with a T-joint.

To facilitate the plumbing work, one could use 6 mm diameter PVC pipes as they can be easily cut and bent to shape for proper installation.

What about Water Borne Diseases?Legionnaire bacterias and algae pores are often found in water of cooling towers of the air-conditioning system; however, legionnaire bacteria will not thrive in air conditioning condensate water because the water temperature are usually below 16 degree C. One may found certain type of algae pores in the condensate water system if the system has not cleaned regularly. Nonetheless, legionnaire bacterias and algae pores are usually more than 3 microns in size. They will be filtered out by the ceramic filter of the WMF which has pores smaller than 0.5 microns. Should some algae or bacterias pass through the ceramic filters, it would not have survived because:

1. There isn't much nutrient in the filtered water to feed the bacterias/pore;
2. The ultrasonic vibrator of the humidifiers would have killed these bacteria/pore as it has some sterilising effects.


Other Usage of Soft Water
Soft water can be used in many areas where scaling is always a problem

a) in steam irons

b) in steamers


c) In Automobile as battery distilled and radiator water.


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