7
STEAM DISTRIBUTOR PIPE LOCATION
It is critical to provide proper routing of flexible
hose and hard tubing to maximize efficiency and
effectiveness. See
Figure B-E
. Not following the
instructions in this Installation, Operation, and
Maintenance Manual could void all warranties, unless
you have consulted with the factory and have prior
written approval.
Each steam cylinder requires a separate
distributor pipe, steam hose, and condensate return line. A
cylinder may supply more than one distributor pipe by using an
accessory “T” fitting but the output cannot be controlled
separately. In a typical installation the humidifier is located
below the duct as shown in
Figure A
.
The distance between
the humidifier cabinet and the steam distributor pipe
should be the minimum distance possible
. Refer to
Table 3
for maximum length that may be installed based
on duct static pressure and pound output. Under less than
perfect conditions, (installation issues, routing problems for
steam and condensate return hose, and extreme steam
hose lengths) it is possible to lose significant amounts of
output.
The use of 90° elbows add approximately three
feet of equivalent length when hard tubing is used, thus
negatively affecting capacity, efficiency, and can cause
back pressure issues and cylinder arching.
The maximum length of steam hose that may be installed
as shown in
Figure B & B-1
is 12 feet. For a steam hose
length over 12 feet refer to
Figure D
. A drain “T” must be
used to remove condensation that occurs in steam hose
lengths over 12 feet. It is preferable to have the steam hose
rise vertically from the cabinet and then slope downward
to the distributor pipe as shown. If sufficient headroom
is not available it is possible to install with an upward
slope but the rise should be 2” in 12” to allow for proper
condensate drainage and steam flow. Carnes electrode steam
humidifiers are non-pressurized, maximum of 1/2 psi. Every
application is different. Hose lengths for small capacity units
will be considerably shorter than larger units. All variables
must be taken into consideration.
MAXIMUM STEAM HOSE LENGTH
(Table 3)
Duct Static
Pressure
“wg”
0 1 2 3 4 5
Maximum Steam
Hose Length (Ft.)
40 35 30 25 15 10
AFFECT ON CAPACITY DETERMINED BY STEAM HOSE
LENGTH
(Table 3-A)
Distance Loss
10 Ft.
1.0 lb./hr.
20 Ft.
2.0 lb./hr.
25 Ft.
2.5 lb./hr.
40 Ft.
4.0 lb./hr.
TYPICAL HOSE LOCATION
FOR LENGTHS UP TO
12 FEET
Figure B-1
Mounting plate
must be plumb.
Condensate hoses
must pitch down
continuously to humidifier
—
NO
pockets, sags
or horizontal runs.
If hose is difficult to
support within this
length, straight
copper tube should
be used and
insulation applied.
Figure B
Outer diameter of drain pipe is 1-1/4”.
Air gap fitting must be added.
Photo C
For a residential unit (HRAB) the maximum length of steam
hose that may be installed is 10 feet.
