[Amps] 8877 blower requirement...TXN ! Now..Airflow sensing ?

[Peter Chadwick]

Peter said:
> instead using a simple microswitch in the airflow path
There is nothing as simple and reliable as that.<
Provided that you can get a big enough vane for the airflow to provide the necessary force to operate the microswitch, and the vane doesn't add so much resistance to the airflow path that you need a bigger and noisier blower. The pressure differential with 1 inch water gauge is roughly 3grams/sq.cm, so you need  a very sensitive microswitch. Possibly you could make something with a big vane and a reed relay.
73
Peter G3RZP