Pressure Sensor - minimum detectable pressure change

[jimbolaya]

I'm working on a sensor to give me the pressure drop across my furnace filter. From what I'm reading I can expect filter inlet and outlet pressures of around 1 inch of water or 2.5 hPa. The sensor spec sheet lists accuracies of around +- 1 hPa. I'm concerned the error may be more than the pressures changes I'm trying to measure. Anyone have any experience with this sensor? Any thoughts? Thx!

[flopp]

Are we talking about BMP280?

Specs for BMP280

[jimbolaya]

Oops. My bad. I thought I listed the sensor. I was looking at the BMP180 on the atmospheric pressure sensor build page. It looks like the BMP280 also has a +- 1 hPa absolute accuracy. Maybe I could take advantage of the better relative accuracy and sample pressure when the furnace is both running and not. The not running pressure would give me a good baseline.