SPeCIfICaTIonS & DIMenSIonS
(ConTInUeD)
Table 2 – water quality Guidelines
Conductivity (uS/cm)
of water connected to
humidifier
estimated grains/gallon
(prior to any water
softening)
Hardness (prior to any
water softening)
Canister behavior
Solution
0-125
0-3
Naturally Soft
Humidifier does not
function .
Installation not
recommended .
125-300
3-9
Naturally Soft
Long start up time .
Power with 208/240VAC,
use constant fan to decrease
time to reach full capacity .
300-500
9-15
Slightly Hard
Optimal performance
range .
Use either hard or softened
water .
500-640
15-20
Moderately Hard
640-840
20-25
Hard
840-1250
25-36
Very Hard
Shortened canister life
due to mineral build up .
Use softened water .
above 1250
36
Extremely Hard
Canister performance
degrades quickly .
Installation not
recommended .
Minerals that are naturally found in water cause the water to be electrically conductive . Water conductivity is measured in micro Siemens per
centimeter (uS/cm) . Mineral content, also described as “water hardness” is usually measured in grains per gallon . Because of the variety of
minerals that are found in water, there is no direct correlation between water hardness and conductivity, but generally the higher the mineral
content, the higher the conductivity .
The Steam Humidifier is designed to operate on water with conductivity between 125 and 1,250 uS/cm . This correlates loosely with water with
hardness between 3 and 36 grains/gallon . Water that is considered “hard” and also softened water work well in the Steam Humidifier . The
humidifier will make steam when plumbed to low-conductivity water but it takes longer to reach nominal capacity .
with low conductivity water, it may take the Steam Humidifier one week or more of operation to reach rated capacity, especially
if it is wired to operate on 120 volts. when operating on 208/240 volts, the Steam Humidifier usually will reach nominal capacity
within a few hours, even with lower conductivity water.
As water in the canister boils and turns into steam, minerals are left behind . Minerals remaining in solution increase the conductivity of the
water . Minerals also deposit onto the submerged portions of the electrodes rendering those areas ineffective . As this occurs, the level of water
in the canister rises to expose uncoated electrode surface .
There are benefits and trade-offs to consider when the application allows a choice between hard and softened water:
Hard water:
The benefit of hard water is less frequent draining and filling than with soft water, which results in better energy and water
efficiency and more consistent steam output . However, canister replacement could be more frequent with hard water, because mineral deposits
coat the electrodes . The harder the water, the more frequent the need for a new canister .
Softened water:
The benefit of softened water is longer canister life (depending on water chemistry) than with hard water, because softened
water does not coat the electrodes nearly as much as hard water . However, softened water ions stay in solution to much higher concentrations
than hard water ions . This requires more frequent draining and filling, which results in lower energy efficiency, higher water consumption and
less consistent steam output .
waTeR qUalITy
7
