CARNES HBGH Installation, Operation And Maintenance Manual page 31

SYMPTOM: DRAINS CONTINUOUSLY
1. The most common cause is to have a
piece of mineral in the drain solenoid valve
that prevents the valve from closing proper-
ly. Simply cycling the "On-Off-Drain" switch
back and forth between "Off" and "Drain" may
dislodge the sediment. In extreme cases it
may be necessary to disassemble drain lines
to clean them. If mineral buildup is re-occur-
ring issue, make sure the "Repetitive Drain
Valve" option is enabled in the settings menu.
2. Check movement of the solenoid actuator
to verify that the plunger moves freely in
the coil. If the coil has overheated so that
movement of the plunger is restricted, it will
require replacement of the valve.
3. When the Drain Valve" LED is lit, the circuit
board is sending 24VDC to the drain valve.
If the indicator is gray but 24VDC is present
at the drain valve, the circuit board may be
defective.
Solenoid Valve
24V DC Coil
Terminals
Valve Shown In
Normally Closed
Position
SYMPTOM: WATER IN THE DUCT
Note: This is usually an installation problem. The first step
is to determine whether water is spitting from the steam
distributor pipe or if steam is condensing on some object
downstream from the steam distributor pipe.
If water is spitting from the steam distributor pipe there may
be several causes.
1. The steam hose and condensate return
line MUST have continuous slopes without
any sags or low areas where water could
accumulate. If water accumulates in the
Must Move Freely,
Clean As Necessary
Water Out,
Into Drain
Clear Plastic End Cap,
Dependent on Model, Could
Be In 3 Different Positions
2.
3.
4.
5.
Water
In - From
Cylinder
Fitting
6.
If water is condensing on an object in the duct or on the
duct itself it will be necessary to take other steps.
1.
2.
3.
31
steam hose it may be suddenly pushed
into the distributor pipe and the condensate
return line may be unable to handle the large
volume.
Make sure that the condensate return line
is not restricted anywhere. Areas where the
hose bends or where it is tied using cable ties
are often the problem.
The distributor pipe must be installed so that
far end of the distributor pipe is higher than
the incoming end where condensate return
connection is located. The mounting plate
on distributor pipes up through 36" should
be mounted on a plumb surface to automat-
ically provide proper pitch. On longer pipes,
it is necessary to support the pipe using the
bracket on the end of the pipe to insure that
proper slope is maintained.
If the condensate return line has a drop of
less than 12" from the distributor pipe to the
top of the humidifier cabinet, it may be better
to route the drain below the unit rather than
connecting at the top of the cabinet.
If the condensate return line is connected to
the fitting at the top of the humidifier cabinet,
make sure that traps have not been installed
in the return line. A trap is only needed if the
return line is routed to a separate drain and
it is necessary to prevent steam from being
discharged from the line.
It may be beneficial, particularly on longer
routes, to put a trap in the steam hose right
before the distributor pipe. In this case, it is
absolutely necessary to run the condensate
at the bottom of the trap away to a separate
drain.
The distributor pipe must be a minimum of
6 feet upstream from any elbow, split, coil,
turning vane, grille or diffuser. The lower
the air temperature is in the duct the further
upstream the pipe must be located. If the
air temperature is 60°F it may be necessary
to have 10 feet between the pipe and any
obstruction.
If it is not possible to have the required
distance from the distributor pipe to an
obstruction a drain pan may be required to
accommodate the water.
It may be that air in the duct simply can't hold
the volume of steam that is being added.
Normally the only practical solution is to
reduce the steam output of the humidifier, as
it is usually not feasible to increase the air
temperature or quantity.