- 16 - - 17 -
9
6
3
7
8
5
2
1
4
1. Note Humidifier Control settingand turn dial to the “OFF” position.
2. Turn off water supply.Turn the integral bypass damper (3) to the SUMMERposition.
3. Press the tabs in the latches on the top and bottom of front cover (1) and pull cover off base
with both hands. Set aside.
4. Carefully pull the plastic feed tube (2) out of the distribution tray (5) at the top of the Water
Panel evaporative assembly (4). Pull this assembly out by grasping at top and tipping out.
5. Unsnap the distribution tray (5) from the scale control insert (8). Lightly scrape out or brush
off any mineral deposits, being careful not to stretch or loosen the synthetic fabric liner.
Soaking the tray in vinegar or a lime-removing agent is helpful when trying to remove
stubborn mineral deposits.
6. Slide the Water Panel evaporator (7) out from the scale control insert (8) and dispose of the
Water Panel. Clean the scale control insert of mineral deposits. Replace the Water Panel
evaporator (Stock No. 35 for Models 600 & 600M and Stock No. 10 for Models 500 & 500M)
with a new Genuine Aprilaire Water Panel. Slide the Water Panel evaporator back into the
scalecontrol insertwiththecoloredspotup andsnapthedistributiontray(5)backintoplace.
7. Inspect the plastic feed tube (2) by gently flexing it and looking for cracks or signs of wear.
Replace tube if it is cracked, brittle, orhas been damaged.
8. Reinstall the Water Panel evaporative assembly (4) into the humidifier by fitting its drain into
the round receptacle at the base of the humidifier. Push the assembly in at the top until it
snaps into place. Push the end of the feed tube back firmly into the distribution tray and
replace the front cover.
9. Remove the drainline (9) from the bottom of the humidifier.If applicable, flex it toloosen any
mineral deposits or blockage. Then flushit with water under pressure. If it does not properly
clear, replace it. Slip drain line back onto the drain fitting. Make sure the drain line has a
constant downward slope and is not flattened or blocked.
10. Turn on the water supply. Return integral bypass damper to appropriate position.
11. Check system operation:
ManualHumidifierControl(Models500M& 600M): With theHVACbloweroperating,turnup
Humidifier Control and check system operation.
Digital Humidifier Control (Models 500 & 600): (Automatic or Manual mode) Check system
operation and reset Change Water Panel indicator by setting the knob to “Test/Reset”.With
HVAC bloweroperatingand HVACcallingforheat, humidifierwill operateforone minute.DO
NOT LEAVE IN TEST MODE AS HUMIDIFIER WILL NOT OPERATE.
12. Set Humidifier Control to its original position.
REQUIRED MAINTENANCE INSTRUCTIONS
(APRILAIRE HUMIDIFIER MODELS 500, 500M, 600 & 600M)
1. Front Cover
2. Feed Tube
3. Integral BypassDamper
4. Water Panel
Evaporative Assembly
5. Distribution Tray
6. “V” Notches
7. Water Panel Evaporator
8. Scale Control Insert
9. Drain Line
CAUTION
Sudden operation may cause personal injury or property damage.
Turn Humidifier Control to “OFF” or lowest setting before servicing.
90-1076
5
4
7
2
6
8
1
3
9
MODEL 500 & 600 SERIES
1. Humidifier Cover
Assembly
2. Base Assembly
3. Water Panel
Evaporative Assembly
4. Distribution Tray
5. ”V” Notches
6. Water Panel Evaporator
7. Scale Control Insert
8. Drain Line
9. Power Cord
1. Note Humidifier Control settingand turn dial to the “OFF” position.
2. Disconnect electrical power andturn off water supply.
3. Unlatchhumidifierfrontcoverassembly(1)frombaseassembly(2)atthebottomofthecover,
lift, and set aside.
4. Pull out the Water Panel evaporative assembly (3) by grasping at the top and tipping out.
5. Unsnapthedistributiontray(4)fromthescalecontrolinsert(7).Lightlyscrapeoutorbrushoffany
mineraldeposits,beingcarefulnottostretchorloosenthesyntheticfabricliner.Soakingthetray
invinegaroralime-removingagentishelpfulwhentryingtoremovestubbornmineraldeposits.
6. Slide the Water Panel evaporator (6) out from the scale control insert (7) and dispose of the
Water Panel. Clean the scale control insert of mineral deposits. Replace the Water Panel
evaporator (Stock No. 35) with a new Genuine Aprilaire Water Panel. Slide the Water Panel
evaporator back into the scale control insert with the colored spot up and snap the
distribution tray (4) back intoplace.
7. Inspect the plastic feed tube by gently flexing it and looking for cracks or signs of wear.
Replace tube if it is cracked, brittle, orhas been damaged.
8. Reinstall the Water Panel evaporative assembly (3) into the humidifier by fitting its drain into
the round receptacle at the base of the humidifier. Push the assembly in at the top between
the retaining ribs that holdthe assembly in place in avertical position.
9. Remove the drainline (8) from the bottom of the humidifier.If applicable, flex it toloosen any
mineral deposits or blockage. Then flush it with water under pressure. If it does not clear,
replace it. Slip drain line back onto the drain fitting. Make sure the drain line has a constant
downward slope and is notflattened or blocked.
10. Reinstallfrontcover assembly (1) by hookingat the top of thebaseassembly(2) andlatching
at the bottom.
11. Reconnect electrical power (9)and turn on the water supply.
12. Check system operation:
Manual Humidifier Control (Model 700M): With the HVAC blower operating, turn up
Humidifier Control and check system operation.
DigitalHumidifierControl(Model700):(AutomaticorManualmode) Checksystemoperation
and reset Change Water Panel indicator by setting the knob to “Test/Reset”. With HVAC
blower operating and HVAC calling for heat, humidifier will operate for one minute. DO NOT
LEAVE IN TEST MODE AS HUMIDIFIER WILL NOT OPERATE.
13. Set Humidifier Control to its original position.
NOTE: The motor is permanently lubricated and does not need to be oiled.
REQUIRED MAINTENANCE INSTRUCTIONS
(APRILAIRE HUMIDIFIER MODELS 700 & 700M)
WARNING
ELECTRICAL SHOCK HAZARD. Can cause injury or death. Disconnect
all electrical power supplies before servicing. Turn Humidifier Control
to “OFF” or lowest setting before servicing.
90-1075
MODEL 700 SERIES