Emerson PFH020A-L, User Manual

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System Testing And Maintenance
61 Liebert
®
Mini-Mate2
™
4. After a period of time, the mineral concentration in the canister becomes too high. When this
occurs, the water boils too quickly. As the water quickly boils off and less of the electrode is
exposed, the current flow decreases. When the current crosses the low threshold point (factory set
at 85%) before the end of the time cycle, the drain valve opens, draining the mineral laden water
out and replacing it with fresh water. This lowers the mineral concentration and returns the
canister to “steady state” operation and prolongs canister life. The frequency of drains depends on
water conductivity.
5. Over a period of time, the electrode surface will become coated with a layer of insulating material,
which causes a drop in current flow. As this happens, the water level in the canister will slowly
rise exposing new electrode surface to the water to maintain normal output. Eventually, the
steady state water level will reach the canister full electrode and indicate so by activating the
canister full alarm. At this point, all of electrode surface has been used up and the canister should
be replaced.
6. After the entire electrode surface has been coated, the output will slowly decrease. This allows for
maintenance scheduling. During these last hours of electrode life, the mineral concentration can
increase and arcing can occur. If the electrodes start to arc, turn off the humidifier immediately
and replace the canister with the identical part.
Replacing the Humidifier Canister
The proper procedure to replace the humidifier canister is:
1. Turn off the humidifier by lowering the humidity setpoint below the ambient humidity level.
Record the original setpoint.
2. Place the RUN/DRAIN switch in the DRAIN position to drain the water from the canister.
3. Return the RUN/DRAIN switch to the RUN position after the canister has drained.
4. Turn OFF the power at the main unit.
5. Remove the cover from the humidifier cabinet.
6. Locate the power wires to the steam canister. They are connected to the canister with 1/4" quick
connects. Make note of the wiring configuration before removing any wires. Refer to schematic on
unit. Slide the rubber boot back to expose the connections. Remove the two (2) power wires and
the canister-full wire. Do not loosen the screws that secure the electrodes.
7. Loosen the steam outlet hose clamps and slide the steam hose away from the canister fitting.
Release the canister clamp along the base of the canister.
8. Remove the canister.
9. Reverse previous steps to re-assemble humidifier, paying special attention to the following:
• When replacing the wiring, connect the red wire from terminal #1 on the interface to the red tip
terminal on the canister. Reconnect the power wires as before (#2 on the left and #1 on the right)
• When replacing the canister, always check the fill and drain solenoids for proper operation.
!
CAUTION
Risk of contact with extremely hot surfaces. Can cause injury.
Canister and steam hose may be hot. Do not attempt to replace parts until the humidifier has
cooled down to a temperature that is safe for human contact.