Furnace filter differential pressure sensing?

[baudneo]

More HVAC monitoring

I have been interested in home energy efficiency for a while so I decided to put together some sensors with an ESP8266 (NodeMCU) to monitor my home’s HVAC system performance. The sensors measure the temperature and humidity of the air on both the return and supply side of the furnace and AC. It also measures the Total External Static Pressure for the duct system. The temperature and humidity is measured with two DHT22s and for the static pressure I am using an Amphenol All Sensors DLHR-L02D-E1B…

I’m using this sensor to get TESP. A side effect is I do see when the filter starts getting clogged.