Thermolec ACU-STEAM User manual

User and Maintenance Manual
for the Homeowner
and
Installation Instructions
for the Contractor
ACU-STEAM™ Humidifier
by Thermolec
Please read this manual carefully before beginning installation.
Important Notice to the Contractor :
Once the installation is complete, please leave this manual with the customer for future reference.
JANUARY 2014 V2.0 US
!
ACU STEAM

Page 1
HOME OWNERHOME OWNER
1. Warnings and Disclaimer – Installation Precautions and Recommendations
Please read and understand the warnings and provided instructions fully before you begin this installation and
keep them handy for future reference.
The manufacturer will assume no responsibility and the warranty will be void if the installer or the user does not
adhere to the following precautions/recommendations :
1.1 Water quality and hardness can significantly affect the maintenance frequency of your Acu-Steam
humidifier. If the cold water supply as measured by grains per gallon (gpg) exceeds 7.0 gpg, the water
is classified as hard and excessive scaling inside the tank reservoir is possible. If the water supply
exceeds 7.0 ppg, a water conditioner/softner is recommended to minimize the maintenance
frequency (see section 8.). Other known benefits of whole house water conditioners/softeners are
improved operation and longevity of plumbing appliances and fixtures.
1.2 This humidifier will be connected to and used under water pressure and it must be installed in such
a way that if a leak occurs, the water will not cause any damage to the property. Make sure all water
connections are properly installed or a water leak could occur.
1.3 This humidifier is intended for use on ducted forced air furnaces and heat pumps as well as multi-
fuel furnaces, which have at least one supply duct connected to the furnace and where a positive air
pressure can be measured.
1.4 Do not install a humidifier where the surrounding temperature may be 32ºF (0ºC) or colder. Freezing
water will damage the humidifier.
1.5 Do not install the humidifier directly on the furnace housing.
1.6 Always check that you are not about to cut or drill into an air conditioning coil or electrical accessory
during installation.
1.7 Do not install a humidifier if the city water pressure exceeds 90 psi. Check the local codes related to
pressure reduction.
1.8 Do not install the diffuser in the supply duct if the pressure exceeds 0.5” Water Column (0.125 kPa).
1.9 The installation, wiring and plumbing of the humidifier must comply with national and local electrical,
plumbing and building codes.
1.10 Electrical wiring and water tubes must not come in contact with sharp edges or hot surfaces.
1.11 Make certain an appropriate drain system is installed and there is no resistance to the flow of the
discharged water.
1.12 Do not set the humidity level higher than that recommended or condensation damage could occur.
1.13 Please beware of sharp edges when you cut into a metal duct.
1.14 Always shut the power off before you start the installation or when doing maintenance.An electric
shock from 120 or 240 volts could cause serious injury or death.
1.15 Caution: when you perform maintenance, please be careful because the unit can be extremely hot.
Always allow enough time for the unit to cool down.
1.16 To prevent electric shock or injuries, never operate the humidifier without the covers as there are high
voltage and hot components inside.
1.17 This humidifier will only work with non demineralized water. The maximum water supply temperature is
86 ºF (30 ºC)
CONTRACTOR

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HOME OWNERHOME OWNER
Instructions and User Manual for the Homeowner
2. View of the unit
2.1 External view of the humidifier. Fig. 2a
2.2 Water Tank Top View. Please see Fig. 2b.
2.3 Water tank Side View. Please see Fig. 2c.
!
ACU STEAM
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6QR8KGY
5VGCO1WVNGV
*GCVKPI'NGOGPV
9CVGT6CPM
(CEVQT[KPUVCNNGFYKVJJQUG
+PVGTPCN&TCKP1WVNGV
'NGEVTKE8CNXG
6CPM%QXGT
6CPM.CVEJ
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Fig. 2c
Fig. 2b
*
*
*Acu-15 model has
two steam outlets

Page 3
HOME OWNERHOME OWNER
3. Startup
3.1 The startup of the humidifier is done as follows :
Adjust the knob on the humidistat to the humidity level (percentage) desired.
Confirm that the water supply valve is open.
Put the main power ON at the electrical panel. The green pilot light comes ON on the LED panel. The
humidifier is ready to work.
Working Principle :
3.2 Unlike other types of humidifiers which produce humidity by passing warm air through a moist pad, Acu-
Steam produces humidity from steam dispersed directly into the supply duct.
3.3 A humidistat (installed either on the wall or the air return duct) controls the unit. You set the knob of the
humidistat according to your desired level of humidity (35-45% recommended). Please read the next section
about the Acu-Steam humidity control.
3.4 When the humidistat senses a need for humidity, it starts the humidification process.
3.5 The tank fills with water.
3.6 The electronic control starts the blower fan in the furnace to move the air as the humidifier starts boiling
water and producing steam. If the fan cannot start (i.e. there is no air movement to transport the steam or
insufficient air pressure), the humidifier stops itself. Please note that it may take a few minutes to bring the
water to a boil. The steam exits the water tank through the steam hose, moves through the steam diffuser
installed in the warm air duct and is released into the duct where it mixes with the moving air.
3.7 As water evaporates, the electric valve opens as needed to replenish the water in the tank.
3.8 When the humidity reaches the desired level, the humidifier stops producing steam. In order to remove
scale and keep the tank as clean as possible, the humidifier drains after a certain number of steam producing
cycles (see section 18.5 on page 24 of install manual for more details).If there is still a demand from the
humidistat after draining, the tank refills and starts to produce steam again. This process is part of the self-
cleaning feature.
3.9 When the humidistat is satisfied, the fan continues to run for a short period of time in order to eliminate
the steam from the ducts and the unit goes to ready mode, waiting for the next call from the humidistat.

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HOME OWNERHOME OWNER
4. How to Control the Humidity
4.1 Humidity level and comfort are personal matters but it is generally acknowledged that a Relative
Humidity of 35-45% is desirable. However, you should take the outside temperature into consideration
before setting the humidity level in order to avoid condensation on the windows. Usually, a narrow strip of
condensation around or at the bottom of the window is considered as normal.
4.2 If you installed an ACU-STEAM humidistat and an outdoor sensor, this adjustment will be done
automatically through a function called outdoor reset. The outdoor sensor automatically reduces the humidistat
setting according to the outdoor temperature during cold days; it does the opposite during mild days. Please
see Fig. 4b for the percentage of relative humidity on the electronic humidistat label. The middle of the scale
corresponds to the middle of the comfort zone, approximately 35% RH (Relative Humidity).
Note: There are no numbers printed on the Humidistat itself.
4.3 If you are using a humidistat by others, the humidity adjustment according to the outside temperature
might have to be done manually. For your information, the following table shows the recommended setting of
the humidistat according to the outside temperature. Please see Fig. 4a.
.
4.4 No matter which humidification system you are using, please do not forget that the humidity level
cannot adjust quickly. It may take some time to build up the humidity to your comfort level. Depending on the
dryness of the house, carpets, furniture, drapes and wood will absorb moisture before you can feel the change.
4.5 If the house remains unoccupied during the winter season, set the humidistat to the minimum set point
in order to prevent condensation.
Fig. 4b
!
35
30
20
40
50
Outside Temprature Recommended Setting
-22ºF (-30ºC) 15%
-13ºF (-25ºC) 20%
-4ºF (-20ºC) 25%
+5ºF (-15ºC) 30%
+14ºF (-10ºC) 35%
above
23ºF (-5ºC) 40%
Fig. 4a

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HOME OWNERHOME OWNER
5. Functions of the Electronic Circuit
5.1 The electronic board located inside the unit controls all the humidifier functions. The front LED panel is
equipped with pilot lights indicating the status of the humidifier. Please see Fig.5a.
Please refer to Article 5.2 for the description of the functions.
The red pilot light, which is a warning light, can either glow all the time or flash when activated.
In case of error, the humidifier enters standby mode. The flashing of the pilot lights indicates which error
happened. The error recognition sequence is as follows :
The green pilot light near the power button blinks once;
The red light flashes a certain number of times, this is the error code;
A pause with no light at all;
Another blink of the green light, once;
Another series of flashing of the red light;
And so on until the condition is reset or service is performed.
Shutting the power OFF at the breaker in the main panel or depressing the power button until the
green light is fully on will reset the error code.
5.2 The ACU-STEAM humidistat also has two pilot lights to indicate the current status.
The green light is lit when the humidistat is demanding for humidity, thus activating the boiling cycle. The red
light indicates a warning and reproduces the same warning code as the red light on the humidifier control
panel. If ever the red light is lit or flashing on the humidistat, you know immediately that the humidifier needs
attention.
Display Status Description
On/Standby
Green light OFF The humidifier has no power – Breaker is OFF.
Blinking The humidifier has power, but is in standby mode.
ON The humidifier has power and is functional.
White button Press to put the humidifier in standby mode.
The green light is blinking.
Press and keep depressed 3 seconds to power
or reset the humidifier. The green light is ON.
Fan
White light ON The fan control is activated.
!
On/Standby - Green
Fan
Warning
Steam
Fill
Drain
- White
- Red
- White
- Blue
- Yellow
Fig. 5a
Mode

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HOME OWNERHOME OWNER
Warning
Red light ON An abnormal condition occurred.
Please refer to the error code table in Section 7.
Steam
White light ON The humidifier is heating water to produce steam.
Filling cycle
Blue light ON The electric water valve is open thus filling the
humidifier.
Draining cycle
Yellow light ON The humidifier is in draining mode.
White button Not active on residential models.
!

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HOME OWNERHOME OWNER
6. What To Do if a Malfunction Occurs
6.1 Shut the main power OFF and restart the humidifier to see if the error code (flashing red light)
disappears.
6.2 If you see a water leak, follow the water supply tube and close the valve installed on the water pipe
located near the humidifier.
6.3 Please refer to the error code table to identify the possible cause of the malfunction and the actions that
you can take.
6.4 Should the problem persist, please call your service company for they are the best qualified to help you.
Describe the problem to them and mention the error code you observed on the front panel. They may be able
to help you solve the problem over the phone. If not, they can call our technical service department.
6.5 Should you attempt to look at the unit yourself, please apply all appropriate safety measures. - Shut the
main power OFF and wait for the unit to cool before you open it.
7. Description of Error Codes
Number of
flashes of
the red light Error Description Humidifier Status Actions to be Taken
by the Technician Reset
OFF No error The humidifier is working fine None
Countinuous
ON The flood sensor under the
tank senses water in the pan.
Humidifier immediately suspends the ongoing
operation. Heating elements and supply valve
are switched off.The power green light is
blinking.
Turn power off. Check for leaks around the
tank clamp, SW valve and drain tube. Make
sure tank arrows align and gasket is sealing
properly.
Automatic Reset
when
Overflow pan dries
up.
1The two water level sensors
are miswired or do not read
the water level properly.
Humidifier attempts to operate, then stops
because of wrong information from water level
sensors. The power green light is blinking.
Turn power off. Clean or replace HLS or LLS
water sensors. Check for proper wiring of HLS
and LLS sensors.
Automatic Reset
when switching
main power ON
3Inadequate water supply. The
supply valve was open for
more than 6 minutes.
Humidifier immediately suspends the ongo-
ing operation. Heating elements and supply
valve are switched off.The power green light is
blinking.
Turn power off. Check SW valve circuit for
24V DC at the valve. Refer to manual (p. 20)
and check for proper drain installation. Make
sure SW shut-off valve is open, SW valve is
responding and SW tube is clear of debris.
Automatic Reset
after
5 min or after
switching power
OFF and ON.
4Inadequate drainage. The
tank did not drain or the
draining cycle is too long.
Humidifier immediately suspends the ongoing
operation. Heating elements and supply valve
are switched off.The power green light is
blinking.
Turn power off. Check for proper drain setup
by referring to manual (p. 20). Check and clean
tank, SS siphon tube and silicon drain tube if
necessary.
Automatic Reset
when switching
main power ON
5
The air pressure switch
does not detect enough air
pressure OR the high limit
HSTAT (optional) senses
extremely high humidity in
the duct.
Humidifier immediately suspends the ongoing
operation. The unit goes back to normal
operation as soon as the error condition
disappears. The power green light is blinking.
Check if the FF motor is running. If not, turn
FF to continuous operation. Check flow sensor
(pitot tube) in duct for blockage, then make
sure plastic tube is connected properly from
flow sensor to PD switch under PC board in
unit (see manual). Change furnace filter if
needed.
Automatic
Reset when
error conditions
disappear
6Temperature inside the
tank exceeded the high
temperature cut-out setting.
The high temperature cut-out has tripped. The
humidifier immediately suspends the ongoing
operation. Heating elements and supply valve
are switched off.The power green light is
blinking.
Turn power off. This is a serious condition and
will likely require assistance from a service
technician. Call 888-854-0995.
After pushing on
the thermal cut-out
button, automatic
reset when
switching main
power ON
Legend: SS = stainless steel, FF = furnace fan, SW = supply water, HLS = high level sensor, LLS = low level sensor

Page 8
HOME OWNERHOME OWNER
8. Maintenance
WARNING : The water tank and its contents can become extremely hot. Please be careful before proceding.
As with any evaporative water device , some minerals normally dissolve in the tank water will create varying
degrees of deposits inside the tank. Even though the unit drains and cleans itself during normal operation,
it will require a minimum annual maintenance check (see sections 8.5 through 8.8) to assure all humidifier
functions and components are operating properly.
8.1 Drain the water from the tank. Most of the time there will be water in the tank even when the humidifier
is in standby mode since it only drains once per set amount of steam cycles (see section 18.5 for drain cycle
settings). First turn down the humidistat to avoid a steam cycle. Please note that when using an ACU-STEAM
electronic humidistat, if the relative humidity is extremely low the humidifier may still run with the knob at
the minimum setting because of a range limiter inside the cover. If this occurs you will need to remove the
humidistat cover by pulling it off and turning the knob completely counter-clockwise. The main power to the
humidifier (the breaker at the main panel, not the power button on the unit) needs to be turned off and then
back on. Once the power is reset the unit will start filling with water (blue LED will light) and keep filling until
draining starts (yellow LED). This process can take a number of minutes. Once draining has completed, turn
the main power off. There should be approximately one inch of water in the tank. Wait a few minutes or until
the unit has cooled before proceeding with the following steps.
8.2 After draining the tank, TURN THE MAIN POWER OFF.
8.3 Remove the cover by turning the 1/4 turn screw to the left.
8.4 Unplug the white quick connect wire connected on the overflow pan at the bottom of the unit. This wire
is connected to the overflow sensor. Please see Fig. 8a.
White Wire Main drain Tube
Overflow Pan
1. Lift 2. Pull
Overflow Tube
Rigid Drain Pipe
Overflow Sensor
Fig. 8a

Page 9
HOME OWNERHOME OWNER
8.5 Pull the plastic tube attached to the bottom of the overflow pan out of the rigid drain pipe on the wall.
You do not have to remove the plastic tube attached to the bottom of the pan. Remove the overflow pan from
the unit by lifting the front of the pan off the screw and pulling it towards you, slightly loosen the front screw if
nescessary. Please see Fig. 8a. Also remove the main drain tube from the rigid drain pipe attached to the wall
and check that both tubes are clean and clear from deposits.
8.6 CAUTION: Check that the water tank is not too hot to handle. Unfasten the latch around the water tank
and remove the tank bottom from the main body of the tank vessel by pulling it down carefully in a twisting
motion. Reminder: there should be a small amount of water in the tank. After you remove the tank, clean the
round o-ring gasket, but don’t discard it.
NOTE :This round gasket is mandatory and the tank will not seal properly without it, likely resulting in
a water leak.
8.7 There will be varying degrees of scale on the tank bottom/sidewalls and interal components which is a
normal byproduct of boiling water containing minerals. Simply discard the scale from the bottom of the tank,
leaving the scale on the tank sidewalls and elements (it will not adversely affect the operation of the unit).
Clean the scale from the bottoms of the stainless steel water discharge and water supply tubes using vinegar
or a cleaning product designed to remove scale, lime or calcium to enable unresricted water flow. If scale is
excessive, affecting the flow of water replace the drain tube and sensors when necessary (normally every 2-4
years); these replacement parts are included in a maintenance kit available from your installing contractor. DO
NOT use any acids when cleaning yourAcu-Steam humidifier.
8.8 Once completed, reinstall the o-ring gasket around the bottom tank collar. Please see Fig. 8b. Align the
two arrows located at the front of the tank and the fixed part while lifting the tank in place. Please see Fig.8c.
Apply even pressure to secure the tank properly in the tank cover. Then close the latch holding the tank in
position. The clamp should close with minimal pressure. Verify that the o-ring gasket and tank are seated
properly by checking for leaks when re-starting the humidifier.
Fig. 8b
Fig. 8c

Page 10
HOME OWNERHOME OWNER
8.9 Put the overflow pan under the tank by sliding the slot on the back screw and hooking the key hole on
the front screw.
8.10 Reconnect the white wire of the overflow sensor on the overflow pan.
8.11 Put the overflow and main drain tubes back into the rigid drain pipe.
8.12 Put the cover back on the humidifier and lock it with the quarter-turn screw.
8.13 When finished, turn the main power back “ON”.

Page 11
HOME OWNERHOME OWNER
9. Preventative Maintenance
9.1 In order to avoid problems due to accumulation of deposits, we suggest that you replace the silicone
drain tube and the low and high water level sensors every 2 to 4 years. We also suggest you replace the round
o-ring gasket around the tank. All these components are available in a kit. Contact your service company for
more information.
9.2 To prepare for the Summer Season
Perform a complete maintenance as described in section 8
Shut the main power OFF
Close the water supply valve
Dry the inside of the tank

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HOME OWNERHOME OWNER
10. Warranty
10.1 Thermolec Ltd. warrants against defects in materials and workmanship of the steam humidifier and
all its components for a period of two (2) years from the date of installation. An Extended Limited Warranty
coverage applies to the following components: 10 years on the element and 5 years on the tank.
10.2 Any claim under warranty shall be considered only if the product has been properly installed, by a
certified technician, and operated in accordance with Thermolec’s written instructions.
10.3 Any misuse of the steam humidifier or any repair by persons other than a certified technician, carried
out without Thermolec’s written consent, voids the warranty.
10.4 All defective parts must be claimed within the warranty coverage period and shall be replaced at no
charge (transport included) by Thermolec. Thermolec does not cover the labor costs to execute the said
repairs.
10.5 Thermolec will not be held responsible for accidental or consequential damages, nor for operational
delays caused by the replacement of said steam humidifier.
Thermolec Ltd
2060 Lucien-Thimens St. Montreal, QC, H4R 1L1
Tel : [phone] Fax : [phone]
Web site : www.thermolec.com
Help line for technical assistance during business hours
Monday to Friday, 8:00am to 5:00 pm (Central Time)
888-854-0995

Page 13
CONTRACTOR
Detailed Instructions for the Contractor
11. Unpacking the Unit
11.1 Contents
Please inspect the carton’s contents and report any missing parts or damage immediately.
1 ea Humidifier
1 ea Main siphon tube (32” long – already installed and coiled inside the unit)
1 ea Steam hose (4 feet long x 1 inch I.D.) / 2 ea Steam hoses for Acu-15
1 ea Steam diffuser (12” or 16”, depending on the humidifier model) / 2x 16” diffuser for Acu-15U
1 ea Instruction and maintenance manual
1 ea Pressure Differential Switch (mounted inside cabinet)
1 Plastic bag containing installation material and hardware as follows:
2 ea Adjustable hose clips for the steam hose / 4 clips for Acu-15
1 ea Small bag - KIT #10S
1 ea Water supply tube (1/4” dia. x 7’ long)
1 ea Overflow tube for the overflow pan (7/16” dia. x 24” long)
1 ea Pitot tube with plastic tube (5/16” dia. X 48” long)
NOTE : The electronic humidistat and the outdoor reset sensor are optional. The humidistat can be either wall
type (RH) or duct type (DH).
11.2 Water Tank Detailed View. Please see Fig.11a.
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Fig. 11a
*
*
*Acu-15 model has
two steam outlets

Page 14
CONTRACTOR
12. Dimensions and Available Models
12.1 Humidifier dimensions Fig. 12a
12.2 Available models Fig. 12b
14”
13”
11 5/8”
9”
!
ACU STEAM
Capacity
Model Lbs/Hr Power Voltage Current
(Kg/Hr) (Kw) (V) (A)
Acu-5U 4.8 (2.2) 1.5 120 12.5
Acu-10U 9.6 (4.4) 3 240 12.5
Acu-15U 12.8 (5.9) 4 240 16.6

Page 15
CONTRACTOR
13. Detailed View and Wiring
View of the top of the unit. Fig. 13a
Green
Yellow
White
Red
Red
Black
Black
Blue Blue
Heating
Element
Electric
Valve
Steam Outlet
Acu-15 model has
two steam outlets
Level
Sensors
High Level
Low Level
Manual
Thermal
Cut-out
Overflow Pan
White

Page 16
CONTRACTOR
View and list of the wire harness by color and function. Please see Fig. 13b & Fig. 13c.
FAN
GIN24V
A
H-STAT A A
ON
1 2 3 OFF
ON
Green Blue Blue Red Red White Yellow
Fig 13b
Fan
Relay
Element
Relay
Element
Relay
Transformer
Fuse
Overflow Sensor
connection
On/Standby
Switch
On/Standby LED
Fan LED
Alarm LED
Steam LED
Fill LED
Drain LED
Ground
connection
Neutral
connection
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YJGPVJGTGKUCFGOCPFHTQOVJGJWOKFKUVCV6JGFT[EQPVCEVKU
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&+2ÄUYKVEJVQCFLWUVVJG
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YKTGFVQVJGUGVGTOKPCNU
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DQCTFCEEQTFKPIVQVJGYKTKPIFKCITCOUWRRNKGF
Description of Wire Harness
Color Function Connected to
Green Grounds the electronic board to
the tank for the level sensors Bracket of the high limit cut-out
Blue/Blue
Pair Powers the electric valve with 24 VDC Electric Valve
Red/Red
Pair Overheat signal High-Limit Cut-Out
White Reads the low water level Low Level Sensor
Yellow Reads the high water level High Level Sensor
Fig. 13c

Page 17
CONTRACTOR
Note: Please read sections 14 and 15 before proceeding.
14. Installing the Steam Diffuser and the Steam Hose
14.1 Proper installation of the diffuser and steam hose is critical for the trouble-free operation of the
humidifier. Please find an accessible location on the duct and make sure you have a minimum length of
35” of straight duct downstream (without elbows or other obstructions on which the steam could condensate),
to allow the steam to disperse easily into the airflow. Once a suitable location has been found make a 1 1/8”
middle insertion hole in the warm air duct for the steam diffuser. For a horizontal duct, make the 1 1/8” hole in
the lower third of the duct height. Please see Fig. 14a. For a vertical duct, make the 1 1/8” hole in the middle of
the duct. Please see Fig. 14b.
Note: For High Velocity systems, the diffuser should be installed in the RETURN and not the warm air duct.
Warning : Before installing anything on a duct, always check that you are not about to cut or drill into an air
conditioning coil or electrical accessories.
14.2 Insert diffuser in duct and align arrow to point up. Fasten the steam diffuser to the duct using four #8 x
1/2” screws provided in Kit #10S. Make sure the holes on the steam diffuser, where the steam exits from, are
pointing up. Please see Fig. 14c.
Note: Acu-15 models are supplied with two diffusers, hoses and clamps, if there are dual ducts install one
diffuser in each duct with equal lenth of hose on each. When installing in the same duct keep a distance of 6”
to 12” between diffusers. Please see Fig. 14d.
Fig. 14a HORIZONTAL DUCT
1/3 H
H
Fig. 14b VERTICAL DUCT
W
Air flow
Air flow
W/2
Fig. 14c
UP
Fig. 14d
6” to 12”

Page 18
CONTRACTOR
14.3 Install one end of the steam hose onto the steam diffuser using a hose clamp and tighten it.
14.4 After installing the humidifier (Section 15) use the second supplied hose clamp, to install the other end
of the steam hose (4 feet long) onto the steam outlet on the top of the water tank and tighten it.
Never try to reduce the diameter of the steam hose or any added rigid piping. It has to be the same as the
diameter of the humidifier top steam outlet fitting. The steam must flow without obstruction.
WARNING : Do not let the hose sag when it is connected to the duct. Please see Fig. 14e.
A sufficient slope with no horizontal section is mandatory to allow any condensation to flow back naturally to
the water tank. Please see Fig. 14f. If condensation water accumulates in the hose, the steam will not be able
to escape normally through the diffuser and will lead to a malfunction of the humidifier. Please keep in mind
that the hose will soften when heated and will have a tendency to sag.
NOTE : If it is not possible to get enough slope for the condensation to return properly to the water tank, then
an S-shaped steam trap (not supplied) must be installed at the lowest point of the steam hose. This steam trap
hose should have a minimum height of 4”. Please see Fig. 14g.
Warm air duct
Warm air duct
Warm air Duct

WRONG
Fig. 14e
IDEAL
Fig. 14f
Min. 12”
CORRECT
Fig. 14g
Unit must be installed a
minimum of 12” below
the bottom of the duct.
Continuous slope without
sagging is MANDATORY.
Cut hose to the shortest
length possible even
though 4 feet is
supplied.
!
A CU STEAM
!
A CU STEAM
!
A CU STEAM