Honeywell H8908B Humidistat User manual

Honeywell
Brand
Honeywell
Model
H8908B Humidistat
Category
Dehumidifiers
Type
User manual

This manual is also suitable for

® U.S. Registered Trademark
Copyright © 1999 Honeywell Inc. • •All Rights Reserved
INSTALLATION INSTRUCTIONS
69- 1341
H8908B Humidistat
H8908C Dehumidistat
APPLICATION
The H8908B Humidistat and H8908C Dehumidistat
(humidity controllers) provide automatic low voltage
control of humidifiers and dehumidifiers or ventilators,
respectively, in central heating and air conditioning sys-
tems. They have a spst, snap-acting, dust-proof switch
and are designed for wall or surface duct mounting.
INSTALLATION
When Installing this Product...
1.
Read these instructions carefully. Failure to follow
them could damage the product or cause a haz-
ardous condition.
2.
Check the ratings given in the instructions and on
the product to make sure the product is suitable
for your application.
3.
Installer must be a trained, experienced service
technician.
4.
After installation is complete, check out product
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 Chronotherm® IV
Deluxe Programmable Thermostats. A mounting tem-
plate 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.
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 install-
ing the H8908 at another location, modify the procedure
to fit the installation.
1.
Hold the mounting template (included) next to the
T8600. Select the mounting side for the H8908.
The template is reversible for mounting on either
the left or right side of the T8600. See Fig. 2.
2.
Mark the holes for the two mounting screws
(included). Then mark the hole for the low voltage
wiring on the template that corresponds with the
side selected in step 1.
3.
Remove the template and drill the holes.
4.
Run low voltage wiring to the location and pull
about 6 in. (152 mm) of wire through the hole.
5.
Plug the hole with nonflammable insulation to
prevent drafts from affecting the control opera-
tion.
Humidity Control
Régulateur d'humidité
-
2
0
°
F
-
1
0
°
F
0
°
F
+
1
0
°
F
+
2
0
°
F
O
v
e
r
2
0
°
F
1
5
%
2
0
%
2
5
%
3
0
%
3
5
%
4
0
%
H
U
M
I
D
I
T
Y
S
E
T
T
IN
G
O
U
T
D
O
O
R
T
E
M
P
E
R
A
T
U
R
E
-
3
0
°
C
-
2
5
°
C
-
2
0
°
C
-
1
0
°
C
-
5
°
C
O
v
e
r
0
°
C
M13371
CASE REMOVAL
SLOT
HOLE FOR WIRING
THE DUCT MOUNTING
INSTALLATIONS
H8908B HUMIDISTAT H8908C DEHUMIDISTAT
69-1341 2
6.
Remove the H8908 case from the base. See
Fig. 1.
7.
Position the base on the wall with the arrow up.
8.
Use the two 1 in. (25 mm) mounting screws to
secure the base to the wall.
Fig. 2. Positioning mounting template.
IMPORTANT
Use 18- to 22-gauge wire for proper wiring.
9.
Connect the low voltage wires to the leads on the
H8908.
10.
Replace the H8908 case.
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).
Fig. 3. Selecting duct location for control.
1.
Locate the control at least 8 in. (203 mm)
upstream from the humidifier (or dehumidifier/
ventilator supply) in the return air duct. See Fig. 3.
2.
Apply the duct template to the duct location.
3.
Use the duct template, Fig. 4, to make the open-
ing and mounting holes for the H8908.
4.
Remove the H8908 case from the base. See
Fig. 1.
5.
Position the foam gasket on the H8908 base.
6.
Position the base on the duct with the arrow up.
7.
Use the four 1 in. (25 mm) mounting screws to
secure the base to the duct.
8.
Connect the low voltage wires to the leads on the
H8908.
9.
Replace the H8908 case.
IMPORTANT
Use 18- to 22-gauge wire for proper wiring.
Fig. 4. Positioning return air duct template.
M13370
THERMOSTAT
WALLPLATE
MOUNTING
TEMPLATE
MOUNTING
HOLES (2)
WIRING HOLES FOR MOUNTING ON RIGHT.
USE LEFT HOLES FOR MOUNTING ON LEFT.
ALTERNATE LOCATION
RETURN
AIR
RETURN
AIR
6 in. (152 mm)
MINIMUM
15 in. (381 mm)
MINIMUM
BEST
LOCATION
RETURN AIR DUCT
M13369
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
mounting holes.
4X DRILL 7/64 IN. DIAMETER
PERCER 4 X 7/64 PO.
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
sur la gaine.
2. Couper le long de la ligne pointillée du gabarit
et percer les trous de fixation.
DUCT TEMPLATE
GABARIT DE GAINE
M13373
H8908B HUMIDISTAT H8908C DEHUMIDISTAT
3 69-1341
WIRING
CAUTION
Personal Injury Hazard.
Power supply can cause electrical shock and
injury.
Disconnect power supply before installation or
servicing.
All wiring must comply with applicable local codes, ordi-
nances and regulations. Make wiring connections
according to humidifier (or dehumidifier/ventilator)
instructions, if available; otherwise, see typical wiring
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 dur-
ing 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.
Fig. 5. Typical wiring diagram for
system with fan interlock.
Fig. 6. Typical wiring diagram for system
with 2-speed fan motor.
Fig. 7. Typical wiring diagram of current
sensing relay with humidifier.
Fig. 8. Typical wiring diagram
of sail switch with humidifier.
Fig. 9. Typical wiring diagram for steam humidifiers.
Fig. 10. Typical parallel wiring of humidity controller
with Chronotherm® IV Thermostat for
dehumidification and mildew control.
1
1
2
PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION
AS REQUIRED.
24 VAC WIRING.
2
HUMIDIFIER
TRANSFORMER
FURNACE
FAN
MOTOR
H8908B
FAN CONTROL
L1
(HOT)
L2
M13368
POWER
SUPPLY
1
1
HL
C
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
24 VAC WIRING.
2
HUMIDIFIER
TRANSFORMER
2-SPEED
FAN
MOTOR
DPST
SWITCHING
RELAY
H8908BFAN CONTROL
L1
(HOT)
L2
M13384
POWER
SUPPLY
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
M13387
1
1
1
FOLLOW THE INSTALLATION INSTRUCTIONS
INCLUDED WITH THE STEAM HUMIDIFIER
TO WIRE THE SYSTEM FAN.
NOTE:
HUMIDIFIER
H8908B
TO
SYSTEM
FAN
HUMIDISTAT
TERMINALS
FAN WIRING
TERMINALS
24V WIRING.
B
O
WY
G
R
HEATING
RELAY OR
VALVE COIL
COOLING
CONTACTOR
COIL
FAN
RELAY
COIL
CHRONOTHERM
®
IV THERMOSTAT
PROVIDE OVERLOAD PROTECTION AND
DISCONNECT MEANS AS REQUIRED.
M13366
H8908C
1
1
69-1341 G.H. 10-99 Printed in Taiwan R.O.C. www.honeywell.com
Home and Building Control Home and Building Control
Honeywell Inc. Honeywell Limited-Honeywell Limitée
Honeywell Plaza 155 Gordon Baker Road
P.O. Box 524 North York, Ontario
Minneapolis, MN 55408-0524 M2H 3N7
H8908B HUMIDISTAT H8908C DEHUMIDISTAT
Fig. 11. Typical series wiring of humidity controller
with Chronotherm® IV Thermostat for
dehumidification and mildew control.
Fig. 12. Typical wiring diagram for HR150,
HR200, ER150 and ER200 Ventilator
or HD220 Dehumidifier applications.
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 humidity every 24
hours. To increase the relative humidity, increase the
sepoint approximately three percent relative 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.
OPERATION AND CHECKOUT
Place the system in operation and observe through at
least one complete cycle to make certain that all com-
ponents are functioning properly.
BO
W
Y
G
R
HEATING
RELAY OR
VALVE COIL
COOLING
CONTACTOR
COIL
FAN
RELAY
COIL
CHRONOTHERM
®
IV THERMOSTAT
H8908C
PROVIDE OVERLOAD PROTECTION
AND DISCONNECT MEANS AS REQUIRED.
M13367
1
1
VENTILATOR/DEHUMIDIFIER
M13383
H8908C
DEHUMIDISTAT
TERMINALS
Outdoor Temperature Recommended
Humidity
Controller Setting°F °C
-20 -29 15
-10 -23 20
0-18 25
+10 -12 30
+20 -7 35
>+20 >-7 40
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Honeywell H8908B Humidistat User manual

Honeywell
Brand
Honeywell
Model
H8908B Humidistat
Category
Dehumidifiers
Type
User manual
This manual is also suitable for
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