19
Basic definitions
Unit hand —
When facing the supply air outlet from the
front of the unit (air blowing in your face), your right hand
will be the right hand side of the unit and your left hand the
left hand side of the unit.
PIPING COMPONENTS
LEGEND
*Check all system component pressure ratings (coils, values, pumps,
etc.) with manufacturer and any applicable local or national piping
codes prior to specifying system pressure rating.
SYMBOL/SKETCH
DESCRIPTION
C
V
FACTOR
RATING*
1
/
2
3
/
4
PSI
F
MANUAL AIR VENT:
Threaded brass needle valve
with screwdriver slot for adjustment.
Application — Body brazed into high point of heat-
ing and cooling coils for bleeding air from coil. Stan-
dard item on all hydronic coils (not used on steam
or DX coils). Should not be used in lieu of main sys-
tem air vents.
N/A
N/A
400
100
AUTOMATIC AIR VENT:
Nickel plated brass valve,
fiber-disc type, with positive shut-off ballcheck and
quick vent feature via knurled vent screw.
Application — Optional replacement for manual air
vent. Automatically passes minute quantities of air
through the fiber discs which expand upon contact
with water, completely sealing the valve. As air
accumulates, the fiber discs dry and shrink, repeat-
ing the cycle. Not recommended for removing large
quantities of air encountered during initial start-up
or subsequent draining and refilling. Should not be
used in lieu of main system air vents.
N/A
N/A
125
240
SWAGE:
Copper tube end expanded to accept a
copper tube of the same size for factory or field
brazing.
Application — Used where possible for all tubing
joints for best joint integrity.
N/A
N/A
300
200
CIRCUIT SETTER:
Variable water flow balancing
valve with manual adjustment knob, pointer, per-
cent-open scale, memory stop and integral pres-
sure read-out ports.
Application — Used for close tolerance water flow
balancing. Positive shut-off ball valve feature allows
usage as combination balancing and shut-off valve.
2.12
3.9
300
250
Cv —
Coefficient of Velocity
DX —
Direct Expansion
Application data
UNIT HAND
