Thermostatic Fan Control, 2-Pipe System With Safety Cycle; Thermostatic Electric Valve Control, 2-Pipe - Carrier 42 SERIES Application Data

Thermostatic Fan Control, 2-Pipe System with
Safety Cycle —
This control is used for high humidity
situations in which condensate problems can occur if fan is
turned off while chilled water is still running through the
coil.
The wiring provides fan cycling from HIGH to LOW on
the cooling cycle and from LOW to OFF on the heating cycle.
An ON-OFF toggle switch replaces the standard 3-speed fan
switch. The toggle switch can be concealed to ensure that
the unit runs on low speed when cooling. This action greatly
reduces the chance of condensation problems that exist with
other standard fan cycling controls.
For control package descriptions, see control components
section entitled Remote-Mounted Controls and Unit-Mounted
Controls.
For NOTES, see below.
Thermostatic Electric Valve Control, 2-Pipe —
A thermostatically controlled 2-position valve provides su-
perior control to fan cycling. With this control, the fan runs
continuously unless it is manually switched to the OFF po-
sition. The fan must be on before the valve can be opened to
supply water to the coil.
This system can be used for normal 2-pipe changeover
systems and can also be furnished for cooling-only or heating-
only applications by omitting the changeover and specifying
which application is intended.
NOTES:
1. Motors are thermally protected.
2. Use copper conductors only.
3. See unit nameplate for power supply. Provide disconnect means
and overload protection as required.
UNIT
LOCATION
TYPE
Vertical Unit Mounted
Vertical
or Wall Mounted
Horizontal
* Packages listed on current price pages.
For control package descriptions, see control components
sections entitled Remote-Mounted Controls and Unit-
Mounted Controls.
UNIT
LOCATION
TYPE
Unit
Vertical
Mounted
Vertical
Wall
or
Mounted
Horizontal
*Packages listed on current price pages. First 2 digits are item
numbers.
†For alternate thermostat with manual changeover. Refer to current
price pages.
5
PACKAGE CODE*
Heating and Cooling
Plus Changeover
24-R
23-17
THERMOSTAT OR
WIRING PACKAGE*
ELECTRIC
Heating and
Heating or
Cooling
Cooling
Plus
Only
Changeover†
Any 2- or
24-M,
24-L
24-N
2-position
22-C, 22-D,
22-A, 22-B
22-E, 22-F
VALVE
3-way,
valve
package.