About the GFX4 Digital Humidistat
In Automatic Mode the GFX4 will adjust the humidity in your home based on the outdoor temperature, lowering the humidity in cold weather to reduce
condensation. The GFX4 can operate in Manual Mode to control humidity to a specific relative Humidity. In most homes, Automatic operation is preferred
to reduce condensation on windows and within the structure. Manual mode is necessary where the outdoor temperature sensor cannot be installed.
Manual mode may be desirable where valuable artwork, instruments or woodwork demand constant humidity. The GFX4 has a dry contact for fan control
(FAN1, FAN2 terminals). The LCD Display is backlit and easy to read. Operation and Installation are simple. The GFX4 can be mounted on an interior wall or
on the return duct of the HVAC System.
WARNING!
This Humidistat must be installed by a Qualified Technician. Always
TURN OFF POWER TO THE HVAC SYSTEM PRIOR TO INSTALLING OR SERVICING
the
Humidifier or Humidistat. Improper operation can result in over or under humidification. Over humidification can result in condensation, structural damage
or mold. Condensation within a building’s structure can cause a loss of structural strength. Condensation can also enable mold and mildew growth resulting
in personal injury and damage to building structure and contents. Older and poorly insulated structures cannot withstand the same humidity levels as
newer well insulated buildings. Read these instructions carefully. This humidistat requires a 24 volt, AC power supply. Improper voltage can cause
malfunction or damage to the control. Do not run outdoor sensor wires on or near line voltage wires. The technical specifications for this product and the
contents of the user manual are subject to change without notice.
Duct Installation
Wall Installation
Outdoor Sensor Location
YES !
North Wall
East Wall
Over Snow Line
Inlet of Air Intake
Less than 200’
from humidistat.
NO!
South Wall
West Wall
Below Snow
Deep in Intake
More than 200’
from humidistat.
YES!
YES!
YES!
YES!
GFX4 Locations
1” Hole.
Wall base has vents.
If wires are run inside wall,
cut rectangular opening.
Secure the base with the
two plastic anchors and
screws.
1” Hole.
Duct base: no vents.
If wires are run inside duct,
cut rectangular opening.
Secure the base with the
two sheet metal screws.
INSTALLATION AND
OPERATING INSTRUCTIONS
!
®
Specifications
Voltage
Switching Load
Outdoor Sensor
Auto Mode
Control Range
Outdoor Temp.
20-30 VAC, 60Hz.
1 amp max. 30 volt
max. 200 ft. 61m.
10%-60% RH.
-10°F, -23°C min.
Manual Mode
Control Range 10%-75% RH
Accuracy -RH (77°F, 25°C)
Accuracy Drift Per Year
Accuracy Indoor Temp.
Accuracy Outdoor Temp.
20%-80% ±4%RH
±0.5%RH
±2°F, ±1°C
±2°F, ±1°C
Resolution, Temp. or RH 1° or 1%.
Relay Close
Relay Open
Setting - 1%RH
S1%RH
With Furnace
Blower Motor
Control
