Carrier 42BHC Fan User Manual


 
21
PIPING COMPONENTS (cont)
LEGEND
NOTES:
1. Motorized spring return 2-way valves have a maximum close-off differential of 25 psi.
2. Motorized spring return 3-way valves have a maximum close-off differential of 25 psi.
SYMBOL/SKETCH DESCRIPTION
C
V
FACTOR
RATING
1
/
2
3
/
4
1 PSI F
2-WAY MOTORIZED VALVE: Electric
2-position flow control valve (open/closed).
Normally closed body with manual override
lever. Installed in supply line to unit.
Application — All standard control and valve
packages are based upon normally closed
valves (valve electrically powered open and
closed by spring return when electric power
removed). Manual override lever allows valve
to be placed in the open position for second-
ary (unit) flushing, constant water flow prior to
start-up, etc. Manual override is automatically
disengaged when valve is electrically acti-
vated. Consult factory for normally open
valve applications.
3.5 5.0 8.0
300 200
SPRING RETURN
3.5 4.6 6.6
POWER ON/OFF
3-WAY MOTORIZED VALVE: Electric
2-position flow control valve (closed to coil/
open to bypass or open to coil/closed to
bypass). Normally closed with manual over-
ride lever. Installed in supply line to unit.
Application — Same comments as 2-way
motorized valve except with manual override
lever engaged the valve is open to both ports
and water flow will take the path of least resis-
tance through the valve package (not neces-
sarily 100% through the coil).
4.0 5.0 8.0
300 200
SPRING RETURN
3.8 5.9 9.0
POWER ON/OFF
Cv Coefficient of Velocity
DX— Direct Expansion