INTELLI-VENT TROUBLESHOOTING GUIDE
Technical Training Department Ashland City, Tennessee © 2005
22 of 24
AIR PRESSURE SWITCHES - DIFFERENT TYPES
The switches shown here are all SPST switches. SPST = single pole, single throw. Power
Vent and Power Direct Vent residential products use the first type shown below.
SWITCH CONTACTS SWITCH ACTION
Normally Open = NO Close on a rise in pressure
Close on a fall in pressure
Normally Closed = NC Open on a rise in pressure
Open on a fall in pressure
Normal State Activated State
Normally open contacts, close on a rise in pressure.
Normally closed contacts, open on a rise in pressure.
Normally open contacts, close on a fall in pressure.
Normally closed contacts, open on a fall in pressure.
To Next Page
Loading...