York J Series Manual page 10

Installation
This state is maintained until the input is deactivated
(contacts open).
Contacts Closed = Smoke Purge Operation
Contacts Open = Normal Operation.
Note that 24 volts (R), terminal 16, must be used as the
24 volt AC source for switching the contact to the unit
controller Shutdown input. Use of any power source
external to the controller will result in damage to the
unit controller.
No external power source may be used
when field wiring any of the above dry
contact inputs. The 24 volt AC source
on terminal 16 (R) of the Terminal
Block CTB1 must be used as the power
source when field wiring these inputs,
as shown in Fig. 1. Failure to do so
will result in improper unit operation
and damage to the unit controller.
10
VAV Heat Relay Output
This is a field wired OUTPUT that is used to command
the VAV boxes to full open during heating mode and
smoke purge operation. This 24VAC signal should have
a maximum current draw not to exceed 20VA. If the
VA requirement of the VAV boxes approaches 20VA,
isolation relays should be field supplied and installed
to avoid overloading the unit power supply.
Note that this signal is used to drive the VAV boxes open
in heating and purge operations.
The VAV Heat Relay Output cannot
exceed a current draw of 20VA. If the
power requirement of the VAV boxes
exceed this amount, isolation relays
must be field supplied and installed
to prevent overloading the unit con-
troller power supply.
FORM 100.50-NOM7 (808)
JOHNSON CONTROLS