Emerson Liebert DS Series, User Manual

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Maintenance
142
Table 62 Steam generating humidifier status lamps: causes, corrective action
Unit Status Lamp
Symptom Corrective Actions Yellow Green
On On
Maximum water level
inside cylinder.
This usually happens on initial startup after replacing the cylinder
(normal).
Water is concentrated with minerals inside the cylinder.
Let unit run, yellow light will disappear when the unit is at full output.
This may take a day or two.
Off Off No power to the board.
Check for main power supply fault.
Turn power switch to DRAIN position. If drain valve is activated
(sound of solenoid), check connection to the board or board itself.
When no sound present, check fuse (replace with 3A, if needed),
transformer (voltage should be present between fuse holder and
ground screw).
One flash
sequence
Off
Excess current. Operating
amperage exceeded 130%
of rated amps. Water is
drained from the cylinder
(drain valve on for 10
min.).
Check drain valve operation, drain time, possible drain restrictions.
Check if fill valve leaks (not holding supply water).
Back-pressure may also cause very conductive water conditions.
Check for short cycling.
Water conductivity too high.
Two
flashes in
sequence
Off
No current detection for 30
minutes with continuous
call for humidity.
Check water level in the cylinder - should be more than one-quarter
full. If it is not, check the fill rate, 24VAC voltage on fill valve terminals
(unit must be on with call for humidity - green light steady on). Verify
fresh water supply to the humidifier. Leaking drain valve can be at
fault (minerals blocking the plunger).
If cylinder is more than ¼ full, check primary power, connections to
the cylinder, continuity of wires to cylinder.
Are power wires connected to proper terminals on the cylinder?
(Color coding)
Low water conductivity.
Three
flashes in
sequence
Off
No current detected with
high water sensor
activated.
Check L1 to ensure that power is properly connected.
Check that L1 wire runs through CT of main PCB.
Cylinder may be defective, check for conductivity between powered
pins and H.W.S. (should be an opened circuit). Ensure all legs are
drawing similar current.
Low water conductivity.
Are power wires connected to proper terminals on the cylinder?
(Color coding).
Foaming.
Four
flashes in
sequence
Off
End of cylinder life; change
cylinder.
Check water level in the cylinder; it should be about three-fourths full.
Check for foaming if water level lower or cylinder life shorter than
expected.
Change cylinder, clean drain valve.
Table 63 Steam generating humidifier troubleshooting guide
Symptom Possible Cause Check or Remedy
Unit in call for humidification,
humidifier will not operate Humidifier not receiving
power
Verify ON/OFF/DRAIN switch is in ON position.
Check fuses or CB's and replace or reset if necessary.
Humidifier Contactor pulled in,
but no water enters canister
No water available to unit Check external water shut-off valves.
Clogged fill line strainer Clean or replaced fill line strainer
Excessive arcing in canister
Drain valve clogged or
defective
Verify that drain valve operates freely when activated.
Clean valve and replace if defective. Flush canister
several times and replace if arcing persists.
Improper water supply
If water is commercially softened, reconnect humidifier to
raw water supply, drain canister and restart. If connected
to hot water supply, reconnect to cold water.
Insufficient drain rate
Verify that drain valve operates freely when activated.
Clean valve and replace if defective. Flush canister
several times and replace if arcing persists.
Excessive mineral
content in water Analyze mineral content of water. If mineral content is
excessive contact Liebert service.