Honeywell H8908B Humidistat Users Manual 69 1341 H8908C Dehumidistat

H8908C to the manual 50348877-b036-4a06-8c81-b0a5daca3422

: Honeywell Honeywell-H8908B-Humidistat-Users-Manual-262079 honeywell-h8908b-humidistat-users-manual-262079 honeywell pdf

Open the PDF directly: View PDF .
Page Count: 4

Download
Open PDF In Browser	View PDF

H8908B Humidistat
H8908C Dehumidistat
INSTALLATION INSTRUCTIONS

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 systems. They have a spst, snap-acting, dust-proof switch
and are designed for wall or surface duct mounting.

Humidity Control
Régulateur d'humidité

OUTDOOR
TEMPERATURE
-20 °F
-30 °C
-10 °F
-25 °C
0 °F
-20 °C
+10 °F
-10 °C
+20 °F
-5 °C
Over 20 °F
Over 0 °C

HUMIDITY
SETTING
15%
20%
25%
30%
35%
40%

INSTALLATION
When Installing this Product...
1.
2.
3.
4.

Read these instructions carefully. Failure to follow
them could damage the product or cause a hazardous condition.
Check the ratings given in the instructions and on
the product to make sure the product is suitable
for your application.
Installer must be a trained, experienced service
technician.
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

HOLE FOR WIRING
THE DUCT MOUNTING
INSTALLATIONS

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.
1.

NOTE: The H8908 electrical connections are not
shared with the thermostat.

3.
4.

2.

5.

•All Rights Reserved

M13371

Fig. 1. H8908B Humidistat.

The styling of the H8908 is designed to blend with the
latest T8600 family of Honeywell Chronotherm® IV
Deluxe Programmable Thermostats. 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.

® U.S. Registered Trademark
Copyright © 1999 Honeywell Inc. •

CASE REMOVAL
SLOT

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.
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.
Remove the template and drill the holes.
Run low voltage wiring to the location and pull
about 6 in. (152 mm) of wire through the hole.
Plug the hole with nonflammable insulation to
prevent drafts from affecting the control operation.

69- 1341

H8908B HUMIDISTAT H8908C DEHUMIDISTAT
6.
7.
8.

Remove the H8908 case from the base. See
Fig. 1.
Position the base on the wall with the arrow up.
Use the two 1 in. (25 mm) mounting screws to
secure the base to the wall.
THERMOSTAT
WALLPLATE

ALTERNATE LOCATION
RETURN
AIR

MOUNTING
TEMPLATE

RETURN
AIR

6 in. (152 mm)
MINIMUM

15 in. (381 mm)
MINIMUM

BEST
LOCATION

RETURN AIR DUCT

M13369

MOUNTING
HOLES (2)
WIRING HOLES FOR MOUNTING ON RIGHT.
USE LEFT HOLES FOR MOUNTING ON LEFT.

Fig. 3. Selecting duct location for control.

M13370

1.

Fig. 2. Positioning mounting template.

IMPORTANT
Use 18- to 22-gauge wire for proper wiring.

2.
3.

Connect the low voltage wires to the leads on the
H8908.
10. Replace the H8908 case.
9.

4.
5.
6.
7.

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).

8.
9.

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.
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.

IMPORTANT
Use 18- to 22-gauge wire for proper wiring.

4X DRILL 7/64 IN. DIAMETER
PERCER 4 X 7/64 PO.

DUCT TEMPLATE
GABARIT DE GAINE
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.

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.

M13373

Fig. 4. Positioning return air duct template.

69-1341

2

H8908B HUMIDISTAT H8908C DEHUMIDISTAT

WIRING

H8908B

WATER
SOLENOID
LEAD WIRE

2

CAUTION

TRANSFORMER

Personal Injury Hazard.
Power supply can cause electrical shock and
injury.
Disconnect power supply before installation or
servicing.

L2

L1 1
(HOT)

CURRENT
LO
SENSING
RELAY
C
HI

All wiring must comply with applicable local codes, ordinances and regulations. Make wiring connections
according to humidifier (or dehumidifier/ventilator)
instructions, if available; otherwise, see typical wiring
diagrams in Fig. 5 through 12.

HUMIDIFIER

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
2 24V WIRING.

IMPORTANT
Select models of fan centers include humidifer
taps so the current sensing relay or sail switch
is not needed.

M13386

Fig. 7. Typical wiring diagram of current
sensing relay with humidifier.
SAIL
SWITCH

H8908B

If not using a current sensing relay or sail
switch, the humidifier must be energized during blower motor cycles for proper operation.

2

TRANSFORMER

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.

1

1 POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
2 24V WIRING.

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.

FAN WIRING
TERMINALS
1

1
FAN CONTROL

1
FURNACE
FAN
MOTOR

HUMIDISTAT
TERMINALS
1

PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION
AS REQUIRED.

2

24 VAC WIRING.

M13368

NOTE: FOLLOW THE INSTALLATION INSTRUCTIONS
INCLUDED WITH THE STEAM HUMIDIFIER
TO WIRE THE SYSTEM FAN.
M13387

Fig. 9. Typical wiring diagram for steam humidifiers.

Fig. 5. Typical wiring diagram for
system with fan interlock.

H8908C

CHRONOTHERM® IV THERMOSTAT

B

FAN CONTROL

HUMIDIFIER

24V WIRING.

HUMIDIFIER

1

POWER
SUPPLY

TO
SYSTEM
FAN

2

H8908B
TRANSFORMER

L1
(HOT)

M13385

Fig. 8. Typical wiring diagram
of sail switch with humidifier.

H8908B
L1
(HOT) POWER
SUPPLY
L2

HUMIDIFIER

L1
(HOT)

L2

2

O

W

Y

R

G

H8908B

L2
DPST
SWITCHING
RELAY

1

H

L
C

2-SPEED
FAN
MOTOR

TRANSFORMER

HEATING
RELAY OR
VALVE COIL

COOLING
CONTACTOR
COIL

HUMIDIFIER

1

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.

2

24 VAC WIRING.

1

M13384

Fig. 6. Typical wiring diagram for system
with 2-speed fan motor.

PROVIDE OVERLOAD PROTECTION AND
DISCONNECT MEANS AS REQUIRED.

FAN
RELAY
COIL

1
M13366

Fig. 10. Typical parallel wiring of humidity controller
with Chronotherm® IV Thermostat for
dehumidification and mildew control.

3

69-1341

H8908B HUMIDISTAT H8908C DEHUMIDISTAT

ADJUSTMENTS

CHRONOTHERM® IV THERMOSTAT

Humidity Control Adjustment
B

O

W

Y

G

R

H8908C

HEATING
RELAY OR
VALVE COIL

COOLING
CONTACTOR
COIL

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.

FAN
RELAY
COIL

Setpoint Adjustment

1

1 PROVIDE OVERLOAD PROTECTION
AND DISCONNECT MEANS AS REQUIRED.

M13367

Fig. 11. Typical series wiring of humidity controller
with Chronotherm® IV Thermostat for
dehumidification and mildew control.

Set the humidity setpoint according to the prevailing
outdoor temperature. See Table 1 for recommended
settings.
Table 1. Recommended Humidity
Controller Settings.
Outdoor Temperature

H8908C

VENTILATOR/DEHUMIDIFIER
DEHUMIDISTAT
TERMINALS

M13383

Fig. 12. Typical wiring diagram for HR150,
HR200, ER150 and ER200 Ventilator
or HD220 Dehumidifier applications.

°F

°C

Recommended
Humidity
Controller Setting

-20

-29

15

-10

-23

20

0

-18

25

+10

-12

30

+20

-7

35

>+20

>-7

40

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 Control
Honeywell Inc.
Honeywell Plaza
P.O. Box 524
Minneapolis, MN 55408-0524
69-1341

G.H. 10-99

Home and Building Control
Honeywell Limited-Honeywell Limitée
155 Gordon Baker Road
North York, Ontario
M2H 3N7

Printed in Taiwan R.O.C.

www.honeywell.com



---

Source Exif Data:

File Type                       : PDF
File Type Extension             : pdf
MIME Type                       : application/pdf
PDF Version                     : 1.3
Linearized                      : Yes
Encryption                      : Standard V4.4 (128-bit)
User Access                     : Print, Copy, Extract, Assemble, Print high-res
XMP Toolkit                     : Adobe XMP Core 4.0-c316 44.253921, Sun Oct 01 2006 17:14:39
Create Date                     : 1999:10:04 11:49:44Z
Creator Tool                    : FrameMaker 5.5.6p145
Modify Date                     : 2007:05:07 15:49:09-05:00
Metadata Date                   : 2007:05:07 15:49:09-05:00
Format                          : application/pdf
Description                     : Installation Instructions
Creator                         : H&BC Technical Communications
Title                           : 69-1341 - H8908B Humidistat H8908C Dehumidistat
Producer                        : Acrobat Distiller 4.0 for Windows
Document ID                     : uuid:3bd554b3-a3ee-461b-aeac-49fea77e74d1
Instance ID                     : uuid:745ad063-adbf-4c3a-bded-645b5dd7171a
Page Count                      : 4
Subject                         : Installation Instructions
Author                          : H&BC Technical Communications

EXIF Metadata provided by EXIF.tools