Copyright © 1995 Honeywell Inc. • All Rights Reserved
PRODUCT DATA
C645A-E
Pressure Switches
FEATURES
•
C645A,B models are for use on natural gas, LP gas,
or air.
•
C645B1047 includes a scaleplate stop to meet
American Gas Association (AGA) requirements for
gas-fired boilers with inputs over 2-1/2 million Btuh.
•
C645C,D models are for use on air only.
•
C645E for use with distillate fuel oil.
•
Spring-loaded diaphragm actuates snap-acting
Micro Switch.
•
Switch can be wired to turn on alarm.
•
C645A,C and D models break control circuit on
pressure fall.
•
C645B models break control circuit on pressure rise.
•
Lockout and manual reset optional in A and C models.
•
Removable, zinc-plated cover protects scaleplate and
adjusting screw.
•
Lockout models have external manual reset lever.
•
Pipe tappings allow selection of positive pressure,
differential-pressure, or venting connections.
•
Optional switch position indicator available.
•
Models of C645A,B available with cover window for
setpoint visibility.
•
Buna-N fiber-reinforced material for increased control
diaphragm strength.
•
Two seal-off diaphragms for added reliability.
60-2159-8
C645A,B with Window
GENERAL
The C645 pressure switches are safety devices used in
positive-pressure or differential-pressure systems to sense
gas or air pressure changes.
C645A,B,D,E
C645C
Contents
General ...............................................................................
1
Features .............................................................................. 1
Specifications ......................................................................
2
Ordering Information ...........................................................
2
Installation ........................................................................... 4
Settings and Adjustments ...................................................
6
Operation and Checkout .....................................................
7
