FYI, the guys at the Filterwatch Kickstarter campaign just added a simple unit that you can connect to an Arduino to measure/alert airflow. Perfect to let you know when your A/C filter or your dryer vent is clogged (which could lead to fire).
The campaign is a bit unclear, but it’s worth it… I’ve pledged, but the campaign needs a boost if it’s going to meet its target. Search for “filterwatch” on Kickstarter, or follow this link:
I plan to use this with my Spark Cores to monitor my dryer vent (I don’t like the thought of fire), my A/C filter (so I can sneeze less), and to monitor my attic fan (last one died and smoked for a while before finally tripping the breaker).
Interesting. I wonder how it would work with modern continuously variable furnace fans like the one I have ? We get rebates here for buying furnaces with these types of fans because they use less electricity. My furnace ramps up the speed and heat if it needs to make up a big difference in temperature, or just stays on low speed to raise the temperature a degree or two.
According to kicktraq they are trending to not meet their goal which is a shame. Hopefully they will get some publicity and catch up.
I think it’s all about the algorithm… and since most filters don’t need to be changed that often… I wouldn’t think the algorithm should respond to a 25% decrease in airflow as soon as it does in that video. It should monitor the trends, peaks and valleys in air flow over periods of time. It should basically learn your system after you change the filter… and then start trying to alert you. If it’s wrong you could adjust it.
KISS method tells me a 30-day beeper would be good enough. My HVAC guy tells me just get the 30-day filters and change them every 30 days whether it looks like they need to be changed or not. Usually it doesn’t look like they need to be changed… but it’s a good routine, and keeps you inspecting the furnace for other issues too on a more regular basis.
I dig that non-moving sensor though and the concept of this is definitely useful
