The H8908B Humidistat and H8908C Deh um idi stat
(humidity controllers) provide automatic low voltage
control of humidifiers and dehumidifiers or venti lator s,
respectively, in central heating and air conditioning systems. They have a spst, snap-acting, dust-proof switch
and are designed for wall or surface duct mounting.
INSTALLATION
When Installing this Product...
Read these instructions carefully. Failure to follow
1.
them could damage the product or cause a hazardous condition.
Check the ratings given in the instructions and on
2.
the product to make sure the product is suitable
for your application.
Installer must be a trained, experienced service
3.
technician.
After installation is complete, check out product
4.
operation as provided in these instructions.
CAUTION
Personal Injury Hazard.
Power supply can cause electrical shock.
Disconnect power supply before beginning
installation.
Location and Mounting
The styling of the H8908 is designed to blend with the
latest T8600 family of Honeywell Chronother m ® IV
Deluxe Programmabl e Thermostat s . A mounting template is included for mounting the H8908 next to the
T8600. The H8908 can also be mounted at any other
convenient location in the living area or equipment
room. See Fig 1.
NOTE: The H8908 electrical connections are not
shared with the thermostat.
H8908B Humidistat
H8908C Dehumidistat
INSTALLATION INSTRUCTIONS
Fig. 1. H8908B Humidistat.
Wall Mounting
IMPORTANT
Mount the control in an area with average
room temperature and average relative
humidity.
The following mounting instructions are for mounting
the H8908 on the wall next to the T8600. When installing the H8908 at another location, modify the procedure
to fit the installation.
Hold the mounting template (included) next to the
1.
T8600. Select the mounting side for the H8908.
The template is rever sib le f o r moun ting on either
the left or right side of the T8600. See Fig. 2.
Mark the holes for the two mounting screws
2.
(included). Then mark the hole for the low voltage
wiring on the template that corresponds with the
side sel ected in st ep 1.
Remove the te mplate and dr ill the holes.
3.
Run low voltage wiring to the location and pull
4.
about 6 in. (152 mm) of wire through the hole.
Plug the hole with nonflammable insulation to
5.
prevent drafts from affecting the control operation.
Fig. 1.
Position the base on the wall with the arrow up.
7.
Use the two 1 in. (25 mm) mounting screws to
8.
secure the base to the wall.
THERMOSTAT
WALLPLATE
MOUNTING
TEMPLATE
RETURN
AIR
6 in. (152 mm)
MINIMUM
BEST
LOCATION
ALTERNATE LOCATION
15 in. (381 mm)
MINIMUM
RETURN
AIR
MOUNTING
WIRING HOLES FOR MOUNTING ON RIGHT.
USE LEFT HOLES FOR MOUNTING ON LEFT.
HOLES (2)
Fig. 2. Positioning mounting template.
IMPORTANT
Use 18- to 22-gauge wire for proper wiring.
Connect the low voltage wires to the leads on the
9.
H8908.
Replace the H8908 case.
10.
Duct Mounting
IMPORTANT
When mounting near an elbow area, locate the
control 6 in. (152 mm) upstream from the
elbow so the element is exposed to the normal
airflow (Fig. 3).
4X DRILL 7/64 IN. DIAMETER
PERCER 4 X 7/64 PO.
CAUTION
Equipment Damage Hazard.
Be careful when selecting control
location and cutting hole in ductwork.
Do not cut or drill into air conditioning
or electrical accessories.
Do not install control on supply (hot air) ductwork.
To use template:
1. Remove backing and apply template to duct.
2. Cut along template dotted line and drill the
MISE EN GARDE
Risque d'endommager le matériel.
Faire attention au moment de choisir
l'emplacement du régulateur et de percer les
trous dans la gaine.
Ne pas couper ou percer les accessoires
électriques ou de climatisation.
Ne pas installer le régulateur sur la gaine
d'alimentation (air chaud).
Utilisation du gabarit:
1. Retirer l'endos du gabarit et placer le gabarit
2. Couper le long de la ligne pointillée du gabarit
M13370
1.
2.
3.
4.
5.
6.
7.
8.
9.
IMPORTANT
DUCT TEMPLATE
GABARIT DE GAINE
mounting holes.
sur la gaine.
et percer les trous de fixation.
RETURN AIR DUCT
M13369
Fig. 3. Selecting duct location for control.
Locate the control at least 8 in. (203 mm)
upstream from the humidifier (or dehumidi fier /
ventilator supply) in the return air duct. See Fig. 3.
Apply the duct template to the duct location.
Use the duct template, Fig. 4, to make the opening and mounting holes for the H8908.
Remove the H8908 case from the base. See
Fig. 1.
Position the foam gasket on the H8908 base.
Position the base on the duct with the arrow up.
Use the four 1 in. (25 mm) mounting screws to
secure the base to the duct.
Connect the low voltage wires to the leads on the
H8908.
Replace the H8908 case.
Use 18- to 22-gauge wire for proper wiring.
Fig. 4. Positioning return air duct template.
69-13412
M13373
WIRING
M13386
L1
(HOT)
L2
1
2
1
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
24V WIRING.
HUMIDIFIER
TRANSFORMER
WATER
SOLENOID
LEAD WIRE
CURRENT
SENSING
RELAY
C
LO
HI
H8908B
M13385
L1
(HOT)
L2
1
2
1
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
24V WIRING.
HUMIDIFIER
TRANSFORMER
H8908B
SAIL
SWITCH
CAUTION
Personal Injury Hazard.
Power supply can cause electrical shock and
injury.
Disconnect power supply before installation or
servicing.
All wiring must c o mply with applica ble local codes , ordinances and regulations. Make wiring connect ion s
according to humidifier (or dehumidifier/ventilator)
instructions, if available; otherwise, see typical wirin g
diagrams in Fig. 5 through 12.
IMPORTANT
Select models of fan centers include humidifer
taps so the current sensing relay or sail switch
is not needed.
If not using a current sensing relay or sail
switch, the humidifier must be energized during blower motor cycles for proper operation.
On multispeed blower applications, do not wire
the high voltage side of the transformer to the
same power source that services the furnace
blower. Premature transformer burnout can
occur.
On HE360 fan powered humidifier models,
only the two yellow wires are connected to the
control. The remaining two red wires are only
used with electronic humidity controls.
L1
POWER
(HOT)
L2
1
2
1
FAN CONTROL
SUPPLY
FURNACE
FAN
PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION
AS REQUIRED.
24 VAC WIRING.
MOTOR
Fig. 5. Typical wiring diagram for
system with fan interlock.
H8908B
TRANSFORMER
HUMIDIFIER
2
M13368
H8908B HUMIDISTAT H8908C DEHUMIDISTAT
Fig. 7. Typical wiring diagram of current
sensing relay with humidifier.
Fig. 8. Typical wiring diagram
of sail switch with humidifier.
FAN WIRING
H8908B
1
NOTE:
TERMINALS
1
HUMIDISTAT
TERMINALS
24V WIRING.
FOLLOW THE INSTALLATION INSTRUCTIONS
INCLUDED WITH THE STEAM HUMIDIFIER
TO WIRE THE SYSTEM FAN.
1
HUMIDIFIER
TO
SYSTEM
FAN
M13387
Fig. 9. Typical wiring diagram for steam humidifiers.
H8908C
CHRONOTHERM® IV THERMOSTAT
L1
POWER
(HOT)
SUPPLY
L2
1
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
2
24 VAC WIRING.
Fig. 6. Typical wiring diagram for system
DPST
SWITCHING
RELAY
2-SPEED
HL
FAN
MOTOR
C
with 2-speed fan motor.
2
TRANSFORMER
HUMIDIFIER
B
O
HEATING
RELAY OR
VALVE COIL
COOLING
CONTACTOR
COIL
WY
FAN
RELAY
COIL
H8908BFAN CONTROL
1
PROVIDE OVERLOAD PROTECTION AND
M13384
DISCONNECT MEANS AS REQUIRED.
Fig. 10. T ypical par allel wirin g of humidity con troller
with Chronotherm® IV Thermostat for
dehumidification and mildew control.
R
G
1
M13366
369-1341
H8908B HUMIDISTAT H8908C DEHUMIDISTAT
CHRONOTHERM® IV THERMOSTAT
BO
1
Fig. 11. Typical series wiring of humidi t y c ont r ol ler
W
Y
HEATING
RELAY OR
VALVE COIL
COOLING
CONTACTOR
COIL
PROVIDE OVERLOAD PROTECTION
AND DISCONNECT MEANS AS REQUIRED.
with Chronotherm® IV Therm ost at fo r
dehumidification and m i ldew control.
H8908C
Fig. 12. Typical wiring diagram for HR150,
HR200, ER150 and ER200 Ventilator
or HD220 Dehumidifier appli cat io ns.
FAN
RELAY
COIL
VENTILATOR/DEHUMIDIFIER
G
DEHUMIDISTAT
TERMINALS
R
H8908C
1
M13383
M13367
ADJUSTMENTS
Humidity Control Adjustment
To maintain optimum humidity control without causing
condensation on cold surfaces such as windows, the
homeowner must adjust the setpoint as the outdoor
temperature changes.
To reduce the relative humidity, reduce the setpoint
approximately three percent relative humid it y ever y 24
hours. To increase the relative humidity, increase the
sepoint approximately three percent re lative humidity
every 24 hours.
Setpoint Adjustment
Set the humidity setpoint according to the prevailing
outdoor temperature. See Table 1 for recommended
settings.
Table 1. Recommended Humidity
Controller Settings.
Outdoor TemperatureRecommended
-20-2915
-10-2320
0-18 25
+10-1230
+20-735
>+20>-740
Controller Setting°F°C
Humidity
OPERATION AND CHECKOUT
Place the system in operation and observe through at
least one complete cycle to make certain that all components are functioning properly.
Home and Building ControlHome and Building Control
Honeywell Inc.Honeywell Limited-Honeywell Limitée
Honeywell Plaza155 Gordon Baker Road
P.O. Box 524North York, Ontario
Minneapolis, MN 55408-0524M2H 3N7
69-1341 G.H. 10-99 Printed in Taiwan R.O.C. www.honeywell.com
Loading...
+ hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.