Intelligent Fan Controller
Installation Manual

Description of Operation
The Intelligent Fan Controller monitors the outside and inside Temperature and Relative Humidity continuously in a range between 40°F to 175°F. When the inside (attic) temperature or humidity increases above a preset level, the fan will activate.
We offer three Intelligent Fan Controllers: Model IFC8a, IFC8b, and IFC8c.

Model IFC8a is designed for areas where "ice dams" or moisture is a problem. The fan will activate when the temperature in the attic (inside) is between 25°F and 175°F, and the inside temperature is 6 degrees or higher than the outside temperature.

In IFC8a, and IFC8b models, the ventilation will stop when the outside humidity is above 80%.

Venting based on the temperature difference offers several substantial improvements over the traditional fan activation based solely on the temperature in the attic.

The fan is activated only when the temperature can be brought down by ventilation (as when the outside temperature is cooler then the inside). The fan is activated for less time than would occur with fan ventilation based on an internal temperature alone. The IFC8a, IFC8b stops the fan from venting during very high humidity, therefore preventing the importation of damaging moisture into the attic. The end result is that heat build-up is prevented by starting the fan ventilation at lower temperatures

The humidity sensors will activate the fan when the inside humidity is 15% more than the outside, the external humidity is below 80% and the internal humidity is above 35%.
.The Intelligent Fan Controller behaves in a manner similar to our electronic thermostats.
Before the IFC8 will activate, the favored conditions must exist for at least 2 minutes. Once activated, the fan will stay on for at least 20 minutes. If the conditions are still present after 20 minutes, the ventilation will continue.

By venting only when the humidity is favored, your attic will stay dryer.

The IFC units contain a "Fan Test" switch, which over-rides the automatic setting.
In "Fan Test On" mode, the fan will run all the time except when the temperature measured by the inside sensor is above 175°F.
For normal operation, set "Fan Test" switch to "Off" position.

Technical Specification IFC8
AC input 120 VAC 63Hz
Maximum fan load 25A on start ups and up to 15A continuous run 120VAC
Power consumption 0.5W at standby and 2W when fan is on (cost of running up to 10c per month)
Operation temperature -40°F to 175°F,
Relative humidity sensing from 0% to 100%

Venting Based on Temperature
Models IFC8 from 25°F to 175°F, user adjustable from 25°F to 105°F, activated when inside temperature is from 6°F to 30°F, user adjustable, more than the outside temperature.
In models IFC8a and IFC8b ventilation stops when the outside relative humidity is above 80%. Model IFC8c does not contain a humidity sensor

If you leave the "Temp>Set" at 80°F and the external temperature is 78°F degrees, the internal temperature is 92°F and the Temperature Range is set to 10°F the temperature light will come on.
In order for the "Fan On" to come on a few conditions must be met:
-The internal temperature must be above the set point " Temp>Set" LED must be on
-The "Temperature" LED must be on
- The "RH <80%" LED must be on
-The above condition must exist for 2-3 minutes.

After 2-3 minutes the "Fan On" light will come on and it will stay for at least 20 minutes. If the difference between an internal and external temperature is reduced below 10 degrees the "Temperature" LED will go off. The "Fan On" light will stay for at least 20 minutes but no more than 30 minutes from the initial turn on. After 20 minutes when Temperature or Temp>Set LED or RH <80% goes off, the ventilation will stop in less than 1 minute.

Venting Based on Relative Humidity
In IFC8a models, the Intelligent Fan Controller activates the fan when the humidity inside is 15% more than the humidity outside. The venting will not start when the Inside Relative Humidity is below 35% or the Outside Relative Humidity is above 80%.

After a * "Favored Condition" is detected, the fan will be activated after two minutes and will continue running for at least 20 minutes. The fan will continue running as long as the "Favored Condition" exists.

* "Favored Conditions" are attained when: The inside humidity is 15% or more than the outside humidity, the inside humidity is above 35% and the outside humidity is below 80%.

IFC8 included: Controller -- dimension: 4"x4"x3", with mounting bracket 4"x 7 1/2"x4",
Inside black cable --10', Outside white cable -- 50', AC cord 15A 2.8", Mounting hardware, Two sensors, and Installation instruction.

Click to enlarge.

8 Light Emitting Diodes (LEDs) Display Status:


Light On Indicates:
Power -- The AC power is connected to the Intelligent Fan Controller and internal power supply is O.K.
Temperature -- Inside temperature is 6°F to 30°F more warmer than the outside temperature.
Humidity -- Inside humidity is 15% or more higher than the outside humidity.
Temp > Set -- Inside temperature is above the user set temperature from 25°F to 100°F. Temperature sensors may activate the Fan On.
Fan On -- The AC power is on at the Controller socket - Fan is running.
Humidity <80% -- Outside humidity is below 80%. Humidity and temperature sensors can activate the Fan On. (On IFC8a and IFC8b models only).
Humidity <35% -- Inside humidity is below 35%. Humidity sensors will not activate the Fan On. Temperature sensors will activate the Fan On.
High Temperature -- Red light plus audio alarm indicates inside temperature is above 175°F or error. Fan On is disabled.

Audio Alarm Messages:
**Humidity >80%, High Temperature and audio alarm: The outside sensor or outside cable is unplugged.
**Temperature >25°F, Humidity < 35%, High Temperature and audio alarm: The inside sensor or inside cable is unplugged.
**Temperature, High Temperature and audio alarm: The inside cable is plugged into the outside jack and the outside cable is plugged into inside jack.

1. The control unit should be installed in close proximity to an AC outlet. Use the screws provided to attach the IFC controller a few feet from the attic floor. If possible, place the front of the controller in front of the attic entrance for easier monitoring.

2. Plug the black inside cable to the connector marked "Inside". Plug the white cable to the jack marked "Outside". Secure the two cables inside the plastic clamp on the top of the controller.

3. Use the provided plastic clamp to attach the black sensor at the end of the black cable approximately 1' from the top of the attic. The sensor should be located away from any potential heat sources, such as a chimney or heat vents. Also, keep the cable away from fans, motors and power cables.

Inside Sensor

4. The next step is to locate a suitable place for the external sensor which is located at the end of the white cable. The sensor has to be shielded from direct sunlight and bright light. If possible, prevent the exposed sensor from wind drafts. Do not allow the sensor to touch any objects directly. One of the easiest accessible places in the attic for this purpose would be a gable. Use the provided hardware to mount the cable away from fans, motors and power cables.

5. Plug your fan into the IFC power outlet.

6. Plug the power cord into the IFC unit. Always unplug the power cord before disconnecting or connecting sensors.

Internal sensor 0.6"x 0.6"x1.75" External sensor 0.6"x 0.6"x1.75" Internal cat5 cable 10' External cat5 cable 50'

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