Reddit mentions of Tjernlund PS1503 Duct Airstat Pressure Switch

years ago a customer bought an inline booster fan for a similar situation you describe and asked us to install it for him. the fan plugs into a 120v outlet and an air pressure switch with a small tubing gets inserted in the duct senses when the main blower turns on. then starts the booster fan. works the same way as all those fantech dryer booster fans that im sure everyone loves to work on lol. its a cheap and easy "fix" for what u are describing. obviously wiring is better for long term. quick google search found this guy on amazon. maybe something similar would be what ur looking for.good luck.


http://www.amazon.com/Tjernlund-Switch-Duct-Pressure/dp/B002EC1O0C

Not wireless, but doesn't require a wire back to the furnace. I have been using something like this for over a year now:

http://www.amazon.com/gp/product/B002EC1O0C/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

It senses pressure in the duct from the furnace blower and kicks the switch on. It needs to be hardwired to interrupt the power to the outlet the fan is connected to.

I ran into one strange issue. My ducts are in unconditioned space in the attic. One day, I left a single window open on the main floor of the house and the wind was blowing directly at the window. The wind increased the pressure in the house enough to pressurize the ducts and kick the fan on a few times. Otherwise, it works really well.