Installation directions for Duct Stat Plug in Thermostat.



*With the use of any electrical appliance, it is important to observe all basic precautions to minimize the risk associated with use, such as electrical shock, fire, or injury to persons. Read these instructions before using your Ductstat® Plug-In Thermostat™.If you have doubts or are unfamiliar with this type of installation work, seek the services of a qualified electrician.  ESPEnergy, LLC. assumes no responsibility for installation of the Ductstat®. For your safety and protection follow all instructions and adhere to applicable building and/or electrical codes.*


In order to prevent excessive stress on the mounting screws support the Ductstat® unit when unplugging connected devices.

Do NOT use the Ductstat® outdoors or in damp locations.

The Ductstat® is intended to control the automatic On/Off operation of In-Line Duct Fans™ installed in the ductwork of forced air distribution systems.

The Ductstat® can also control the line voltage to any electrical device with a maximum 5 Amperes for inductive loads. All Suncourt In-Line Duct Fans™ are inductive loads.

The Ductstat® is equipped with an external, replaceable 5 AMP fuse to protect the electronic circuitry from overload or short circuits.


1. Locate the position between the In-Line Duct Fan™ and the register where you wish to mount the Ductstat® Mount between 1 and 10 feet downstream from the In-Line Duct Fan™.

2. Tape the template supplied with the Ductstat® to the air duct to mark the mounting holes to be drilled.

3. Drill a hole in the air duct for the Air Intake Hole shown on the template. This hole should be ˝" in diameter.

4. Drill holes in the air duct to line up with the appropriate holes located on the template. On round ducts, two screws placed through the slots in Ductstat® unit's base will be adequate (placement shown on template). On square or rectangular ducts use four screws, one at each corner of the Ductstat® (placement shown on template).

5. Tighten the supplied screws snugly in the appropriate placement for your ductwork. DO NOT OVER TIGHTEN

6.Wire a grounded power cord to the In-Line Duct Fan™ and plug into the outlet on the face of the Ductstat® unit.

7. Plug the Ductstat® power cord into a 110 volt grounded household outlet.

8. Follow Operation/Settings to adjust the Ductstat® unit.


Function switch selections: OFF to stop operation of the In-Line Duct Fan™.

ON for continuous running of the In-Line Duct Fan™.

AUTO HEAT for automatic on/off to boost warm air.

AUTO COOL for automatic on/off to boost cool air.

The Sensitivity Differential switch provides control over On/Off cycling.

FOR HEATING Position the Function switch to AUTO HEAT.

FOR COOLING Position the Function switch to AUTO COOL.


 STEP ONE  Turn counter clockwise until fan motor runs

 STEP TWO Turn clockwise to point where the fan motor stops 



STEP ONE  Turn clockwise until fan motor runs 

STEP TWO  Turn counter clockwise until fan motor stops




To shorten the length of time that your In-Line Duct Fan™ continues to run after the forced air furnace or air conditioner has shut off rotate the set point knob control slightly further as in step two.

Should you experience frequent on/off cycling move the set differential switch to max position. NEVER EXPOSE YOUR DUCTSTAT® TO TEMPERATURES OVER 160°F (71°C)


1. Make sure the blower on your furnace is not running.

2. Set the Sensitivity Differential switch to the MIN position.

3. Set the Function switch to Auto Heat (winter) or Auto Cool (summer).

4. To adjust the In-Line Duct Fan™ motor ON/OFF point rotate the Set Point knob in the proper direction for your heating or cooling application until the In-Line Duct Fan™ motor switches ON, then slightly turn the control knob in the opposite direction until the In-Line Duct Fan™ motor stops. DO NOT FORCE.

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