Component Operation and Maintenance, Checks and Adjustments
60
Controls
The humidifier RUN/DRAIN switch is located in the unit low voltage compartment for most Deluxe
models (in the humidifier assembly for models FH599, 600, 739, 740C). This switch should be in the
RUN position when the humidifier is in normal operation; it should be in the DRAIN position when a
manual drain for service is required. The electronic control board for the humidifier is located in the
same area as the humidifier RUN/DRAIN switch. When the main unit is energized, power is available
to the humidifier circuits.
Figure 11 Run/drain switch
Replacing the Canister
See
Step 5
of
Operation
in
7.5.2 - Steam Generating Humidifier
for indications that a canister
may need to be replaced.
To replace the canister:
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. FOR ALL MODELS EXCEPT FH599C, 600C, 739C and 740C, refer to replacement instructions
that accompany replacement kit 153315P1 and P2.
7. For models FH599C, 600C, 739C and 740C, locate the power wires to the steam canister. 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 three power wires and the canister full
wires at terminals 1,2 and 3. Do not loosen the screws that secure the electrodes.
8. For all models, use a screwdriver to remove the hose clamps that secure the drain and overflow
hoses from the canister ports.
9. Loosen the fill line compression fitting and remove the tube from the input canister port.
10. Loosen the steam outlet hose clamps and slide the steam hose away from the canister fitting.
Release the canister clamp along the best of the canister.
!
WARNING
To avoid a shock hazard, all power to the unit must be disconnected before proceeding with
the canister replacement procedure.
!
WARNING
The canister and steam hose may be hot! Allow time for the humidifier to cool before replacing
parts.