it in ordinary household vinegar. If the pad is covered by
a heavy deposit of scale, or if the local water supply has
high sulfate or calcium content, replace the pad with a
new one. Contact your dealer for replacement part.
6. Reassemble your humidifier.
7. Turn on the electrical power and water supplies. Refer to
the start-up procedures.
P110-WTR2019A HUMIDIFIERS
1. Turn off all electrical power to the humidifier and furnace
or fan coil.
2. Turn off the humidifier’s water supply. (See Fig. 3.)
3. Drain water from the unit. Place a pail underneath the
drain plug located on the bottom of the humidifier cabi-
net. Lift the tab on the drain plug and remove the plug.
Allow all water to drain from the unit. (See Fig. 10.)
4. Remove the front door from the humidifier. Rotate the
latches one-half turn, then pull the door forward.
5. Remove and inspect the evaporator pad assembly. Lift
the bearing from its retainer. (See Fig. 9.) Pull the as-
sembly away from the motor to disengage the assembly
shaft from the motor coupling. Remove assembly through
the access opening.
Inspect the evaporator pad. If the pad is heavily loaded
with scale, or if the local water has a high sulfate content,
replace the pad. Contact your dealer for replacement part.
NOTE: For best performance, the evaporator pad should
be replaced before each heating season.
6. Inspect the float assembly. Remove the float arm from
the valve body by sliding out the pin and lifting off the
float arm. (See Fig. 11.) Inspect the rubber valve seat lo-
cated inside the float arm. If the seat appears to be nicked
or worn, invert the seat or replace it with the spare valve
seat located on the float arm. Inspect the water opening
in the valve body. If the opening is clogged, use a pin to
remove the obstruction. Remove any accumulated de-
posits from the valve body and float arm.
7. Clean the water pan and unit cabinet. Tilt the water pan
and lift it from the unit. Wash the pan with warm, soapy
water. Flex the pan to loosen accumulated scale. Wash
the unit interior, removing any accumulated deposits. In-
spect the drain line to ensure that no blockage has oc-
curred. Clean as required. (See Fig. 10.)
8. Reassemble your humidifier. Reinsert the water pan and
drain plug. Ensure that the overflow tube is inserted into
the hole at the bottom of the cabinet. Attach the float arm
to the valve body by aligning the holes on both parts and
reinserting the pin. Do not force or bend the pin. The float
arm should have free up-and-down movement. Install the
evaporator pad assembly. Ensure that the square shaft en-
gages the motor coupling and that the bearing washer is
located inside the bearing retainer. Turn the water on. Ad-
just float by rotating until water covers inside of foam
drum. Attach the access door and turn the latches.
9. Turn on electrical power supplies. Refer to start-up pro-
cedures listed on page 2.
BEFORE YOU REQUEST A SERVICE CALL
Before You Call For Service, Check For These Eas-
ily Solved Problems:
• Check the main power disconnect switch. Verify that the
circuit beakers are on and that fuses have not blown. If
you must reset breakers or replace fuses, do so only once.
Contact your servicing dealer for assistance if the break-
ers trip or the fuses blow a second time.
• If the humidity level is too low, check the humidistat set-
ting. Confirm that the saddle valve is turned on. Check the
evaporator pad, and clean or replace the pad as necessary.
Check water level in P110-WTR2019A humidifier.
• Check for sufficient airflow. Check the furnace filter or elec-
tronic air cleaner for excessive accumulations of dirt. Check
for blocked return- or supply-air grilles. Be sure grilles are
open and unobstructed.
• If water drips from the humidifier, check the drain hose
for kinks or obstructions. On P110-WTR2019A humidi-
fiers, dripping may indicate that the float valve requires
adjustment.
• If your comfort system still fails to operate properly, con-
tact your servicing dealer for troubleshooting and repairs.
Specify your apparent problem, and state the model and
serial numbers of your equipment. (You should have them
recorded where noted in this booklet.) With this informa-
tion, your dealer may be able to offer helpful suggestions
over the phone, or safe valuable time through knowledge-
able preparation for the service call.
Regular Dealer Maintenance —
In addition to the rou-
tine maintenance that you perform, your humidifier should
be inspected regularly by a properly trained service techni-
cian. The inspection (preferably each year, but at least every
other year) should include the following:
• Routine inspection of the humidifier. Cleaning, if nec-
essary. Cleaning or replacement of the evaporator pad
as required.
• A check of all electrical wiring and connections.
• A check of water connections to the unit.
• Operational check of the complete comfort system to
determine actual working condition. Necessary repair
and/or adjustment should be performed at this time.
Your servicing dealer may offer an economical service
contract that covers seasonal inspections. Ask for further
details.
HUMIDIFIER HOUSING
WATER PAN
OVERFLOW TUBE
DRAIN PLUG
Fig. 10 — Cleaning Water Pan and Unit Cabinet —
P110-WTR2019A
FLOAT ARM
PIN
VALVE SEAT
VALVE
BODY
HIGHER
LOWER
Fig. 11 — Float Arm Removal — P110-WTR2019A
4
