Pneumatic Session #2 -- Thermostats and Controllers: Clip 2 of 6

[ictraining]

Sometimes buildings need to bring back the night setting to all of the stats that have been overridden (on Friday night or Saturday). One strategy that is used to return all of the stats is to switch to the day pressure for a few minutes then back to the night pressure . This way all of the stats will go to the energy saving setpoint for the remainder of the weekend.

[ictraining]

in a day night tstat, pressing the button in the day will have no effect. the button will return to the day position.

at the night inlet pressure it uses the internal pressure present in the stat to keep the over ride button in place for the higher daytime setting when the button is pressed. At day pressures, that pressure (typically the higher pressure) is not present so the button snaps back to the non-over ride position.

[odess4sd4d]

Thanks for the response. At first I didn't understand it because on my system the indexing switches didn't pop back up during day mode. I finally realized that the thermostats had been damaged by bad air at some point. As I have replaced them I see that in day mode they do pop right back up. This channel is a fantastic resource. Thanks again.

[odess4sd4d]

On the dual thermostat, if the manual override push button is depressed during the day (15 psi supply), does it have any effect? Is the push button supposed to automatically return to the up position, if so, what triggers that?