State Industries SHE50-100NE Air Pressure Switches, Normal State, Activated State, Construction

ULTRA HIGH EFFICIENCY POWER VENT/POWER DIRECT VENT - SERVICE MANUAL

AIR PRESSURE SWITCHES

Air pressure switch technical bulletins TB-A023-06 and TB-S023-06 explain air pressure switch construction and test procedures in detail. These technical bulletins are available on the manufacturers web site or by calling the technical support phone number shown on the water heater labeling. Construction and types of air pressure switches used on the water heater covered in this Service Manual are shown below.

Construction
Normal State	Activated State
(open switch contacts)	(closed switch contacts)
Switch Contacts Wiring Terminals
Internal Linkage
Vent Port
Flexible Diaphragm	Sensing Port
Application & Type
Normal State	Activated State

Blower Prover

Air Pressure Switch

Normally open contacts, close on a rise in pressure.

Blocked Intake

Air Pressure Switch

Normally closed contacts, open on a fall in pressure.

Blocked Exhaust

Air Pressure Switch

Normally closed contacts, open on a rise in pressure.

Technical Literature Department	18 of 52	Ashland City, TN © 2008
Servicing should only be performed by a Qualified Service Agent