Pressure switch in gas furnace

In my experience, these are usually flow switches rather than pressure sensors per se. A lollipop-shaped metal arm extends in to the flow path of the air moved by the fan, and is connected to a simple contact switch. The moving air pushes against the broad head of the lollipop, deflecting it and putting pressure on the switch. Dead simple, cheap, and low tech. Use an off-the-shelf microswitch and a pair of tin snips to fab one in 5 minutes or less

List of Manufacturers Cleveland,Antunes, honeywell,robertshaw-white. I am talking airproving switches commonly used on power burners boilers etc. Most common are Cleveland and Antunes

thanks

do you have pricng for big quantities to Oem's ?

rgds

thanks for comments

y're right for older furnaces ; for new ones pressure switches

do you know Oem prices for both types ( price for big quantity )

for 2 stage gas furnaces where 2 pressure switches used , can you imagine if future solution could be a pressure sensor ( giving information electronically to control board ) ?

rgds