Residential humidifiers are designed to send periodic sprays of mist into the air to raise the humidity of a room or several rooms in the house. The humidifier is a storage container of water until it is close to evaporation to make the transfer into water vapor more effective. However, sometimes white dust and crusts can build up in the humidifier, a sign that you may need to add demineralization tablets to the water to keep it clean and fresh.
When the humidifier heats up the water in preparation for spraying, it is also changing the chemical relationship that the water molecules have with other particles that may be attached to them. Hard water contains a high number of these mineral bonds, which are weakened by the heat. The minerals precipitate from the water and collect on the sides and in the nozzle of the humidifier. The tablets are designed to keep the process from damaging the humidifier.
The primary ingredient in the tablets is sodium chloride, a basic form of salt. Salt is also used to create the resin household water softeners use. When combined with an electrical current, water softeners can exchange the mineral ions with sodium ions from the salt. The sodium does not interact with heat in the same way and deposits are not formed. The only downside is high levels of salt in the water. The tablets are designed to encourage a similar process, only on a much smaller scale.
Sometimes the demineralization tablets are made of potassium chloride instead of sodium chloride. Potassium chloride has many of the same characteristics as salt when it comes to replacing mineral ions. But as a metal halide salt, the tablets may be easier for some manufacturers to produce -- depending on their location and access to resources -- and do not raise the salt level of the humidifier spray.
Some humidifiers have demineralization cartridges instead of tablets, which may be more effective at getting rid of hard water problems. You should also note that if your humidifier is showing hard water effects, your boiler pipes probably are as well. It may be worthwhile to invest in a whole house water softener, which would solve both problems at once.
- Photo Credit Hemera Technologies/PhotoObjects.net/Getty Images