Herrmidifier Herrmidicool Technical Guide - Manual (Page 5)

The heart of the Herrmidicool system is the unique
patented Herrmidicool Atomizing Head, which is
designed to be self-cleaning, dripless and extremely
efficient. The internal atomization design requires only
0.12 SCFM at 30 psi for every pound of water per hour
atomized--a 100 lbs/hr system requires only 12 SCFM!
The stainless steel cleaning needle coupled with special
controls insures self-cleaning of all orifices and drying of
the head on shutdown. This self-cleaning technique
makes the head impervious to mineral content and
ambient contaminants. A special spring-loaded silicone
seat insures positive shut off of the pressurized potable
water line on shut down and eliminates any possibility of
viral or bacterial contamination. The atomizing head is
modulated through means of a modulating valve
producing a full 30:1 turndown, with droplet sizes
ranging from 0.3 to 10 microns.
An optional "blow-down" assembly completely empties
the lines of all water on shutdown - positive freeze
protection for roof top installations.
Two basic version of the control cabinet are available:
the AH-1200 (includes necessary sensor and air proving
switch) and the AH-1205 (Designed for DDC Interface).
AH-1200 Series (Stand-alone Proportional + Integral)
1.
When the relative humidity drops below the predetermined set-
point, the return air plenum sensor will send a signal to the
controller in the Herrmidifier Control Section.
2.
When a high limit duct sensor is used, a signal is transmitted to
the controller with a decreasing signal as the relative humidity in
the discharge plenum approaches the high limit set point.
3.
The controller will compare the two input signals with the
humidity setpoint and supply the appropriate signal to the
modulating water valve.
4.
If the system employs a two-stage output system, the control
logic will provide modulating signals to each water valve.
A duct airflow sensor provided with AH-1200, will shut down the
system automatically if there is no movement of air in the duct.
If so desired, the Herrmidicool system will be interlocked to preclude
simultaneous operations of mechanical cooling and evaporative
cooling.
AH-1205 Series (DDC)
1.
When the relative humidity drops below a predetermined set-
point, the Building Management System will send a signal to the
controller.
2.
When a high limit duct sensor is used, a signal is transmitted to
decrease the control signal as the relative humidity in the
discharge plenum approaches the high limit set point.
3.
The DDC controller will compare the two input signals with the
humidity setpoint and supply the appropriate demand signal to
the Herrmidicool Control Cabinet. The Herrmidicool controller will
condition the signal and transmit it to the modulating water valve.
4.
If the system employs a two-stage output system, the control logic
will provide modulating signals to both water valves.
It is recommended that a duct airflow sensor be used in the application,
it will shut down the system automatically upon a loss of airflow in the
plenum
If so desired, the Herrmidicool system will be interlocked to preclude
simultaneous operations of mechanical cooling and evaporative
cooling.
HERRMIDICOOL Technical Manual