Trane EHUMD800ASM00BA Installation & Maintenance Instructions Manual page 3

MATERIALS LIST
MATERIALS FURNISHED WITH MODEL
EHUMD800ASM00BA / EHUMD800BSMLCBA
Humidifier
Manual humidistat and blower activation relay
Dispersion tube
Steam hose (6 feet)
7/8" I .D . drain tubing (10 feet)
Hose clamps
Saddle valve
Mounting screws
PRINCIPLES & SEQUENCE OF OPERATION
The Steam Humidifier delivers humidity in the form of
steam to the conditioned space via the HVAC system
duct . The humidifier generates steam by energizing two
electrodes that extend into a canister of water . Current
flowing between the electrodes causes the water to boil,
creating steam . Water is introduced to the humidifier
through a fill valve to a fill cup located in the top of the
cabinet . The fill cup serves as an overflow reservoir and
provides an air gap between the humidifier and water
source . The steam canister is filled from the bottom . The
canister is seated in a drain cup assembly which includes
a drain valve . The drain and fill valves work together to
maintain water level in the canister to deliver the rated
steam capacity based on the electrical conductivity of
the water and to temper drain water . See Figure 1 for
representation of fill and drain system and canister .
To control the Steam Humidifier as part of the HVAC
system, a Connected Thermostat Control with an integral
humidistat is installed to detect the RH level in the duct .
When the humidistat detects RH below the set point, and
the humidifier and HVAC system blower are operating,
the humidifier energizes the electrodes to provide steam .
Steam is delivered into the duct work via the steam hose
and through the dispersion tube . The dispersion tube
is fitted with opening called "Tubelets
the dispersion tube and Tubelets distribute steam over a wide area in the duct and direct any condensed moisture back into the steam hose . A
blower activation relay is included to turn on the HVAC system blower to maintain the proper RH level even when the furnace or air handler is in
stand-by mode . When using a Connected Thermostat Control with the Steam Humidifier, the provided manual humidistat and blower activation
relay are not used .
FIGURE 1 – Fill and Drain System and Canister
Inlet
Fill Valve
" . The design of
™
NOT FURNISHED
Main power disconnect switch
Wiring
1/4" O .D . supply water tubing
Boards for mounting (if required)
Overflow
Steam
Outlet
High Water Level Sensor
Fill
Drain Valve
Drain Cup
Supply
Water
Drain
Tubelets
Dispersion Tube
in Duct
Steam Hose
Electrodes
Canister
90-1522
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