Cylinder Life; Calculating Humidity Load - GeneralAire Elite Steam Manuel D'utilisation

1.2

Cylinder Life

1.2.1 Basics of the Steam Cylinder
The Steam Cylinder is the engine of the humidifier. As the humidifier operates water is evaporated and minerals are left
behind. Much of these minerals are removed through the cylinder drain. Some are deposited on the walls of the cylinder and
the cylinder electrodes. When a lower section of the electrodes develop a thick coating, the water level is raised to expose
clean electrode surface. Eventually minerals cover the electrodes' entire length with a thick coating and little electrical current
can pass between them resulting in poor steam output. The humidifier can sense the low amperage and will display the E6
Cylinder Exhausted error code. There are several factors that influence cylinder life.
1.2.2 Water
Characteristics of water influence cylinder life and can vary greatly from place to place. Total mineral content of the water is
important. Equally important is what minerals are present in the water. Most water conditions result in flaky scale that
eventually fills the bottom of the cylinder until it can no longer function. Water with high silica content can result in a thin
glass-like coating on the electrodes that is highly insulating resulting in shorter cylinder life. Only cold water is to be used.
Water conductivity that is not matched to the correct cylinder will shorten cylinder life.
1.2.3 Water Filtration
Typically additional filtration of the incoming water supply is not necessary. If, however, mineral content is known to reduce
cylinder life excessively or if cylinder life proves insufficient then water filtration can be added. In most cases the addition of a
two element water filter can improve cylinder life. The filter should contain an activated carbon element and a particulate filter
element rated for 5 microns or less. Micron is a size measurement. The filter system should have a flow rate of at least 2
GPM. The activated carbon will absorb much of the mineral content while the particulate filter will catch any granular material
or sediment. It is important to remember that the increase in cylinder life will be accompanied by the need to replace filter
elements with each cylinder change.
1.2.4 Humidity Load and Cylinder Life
Humidity load demands have an effect on cylinder life. Normal installations where humidity capacity is properly sized require
only intermittent periods where full humidifier capacity is required. This allows the water level in the cylinder to be increased
only as electrode segments become insulated. This tends to maximize cylinder life.
Extraordinary installations that require constant operation at full capacity reduce cylinder life. The water level in the
cylinder is, on average, much higher, and the electrodes become completely insulated more quickly. Installations like this
may result in cylinder life of less than 1000 hours.
The importance of providing adequate humidifier capacity should not be underestimated.
1.2.5 Maximum Production
Another factor affecting cylinder life is the maximum production setting. A higher production
rate will result in a shorter cylinder life. For this reason DS-25 and RS-25 units are preset from
the factory at 70%. Further reductions in Maximum Production will extend cylinder life.
See Figure 1.c.
1.2.6 Structures Under Construction
In high end construction projects, humidification is often required while the structure is being finished. Humidification is
necessary to protect and stabilize wood floors, trim and decoration. Humidification load, however, in an unfinished structure
may be five to eight times higher than when finished. Elite Steam humidifiers may be operated while construction is underway
but, reduced cylinder life is to be expected and budgeted for. Good practice dictates that the steam cylinders also be
replaced once the project is complete.
1.3

Calculating Humidity Load

1.3.1 Steps to Determine Humidity Load
Total Square Footage
x Average Ceiling Height
x Factor From Table 1.2
x 1.05 for each Fireplace
Humidity Load in lbs./hour
x 2.88 convert to gallons/day
Gallons per Day Humidity Load
*Based on .5 air changes per hour.
Elite Steam +030222075 Rev. 4.0 – 2 Mar. 2015
Table 1.2 Pounds of Moisture / Hour / Cubic Foot *
Indoor Air 35%
Temp °F
68 0.00015
70 0.00017
72 0.00019
* Based on .5 air charges per hour.
5
Cylinder
Life
Fig. 1.c
100%
Indoor RH%
40% 45%
0.00018 0.00021
0.00020 0.00023
0.00022 0.00025
20%
50%
0.00024
0.00026
0.00028