Aprilaire 800 Series Installation & Maintenance Instructions Manual page 27

MAINTENANCE TROUBLESHOOTING GUIDE
5. Slide canister up and out of drain assembly (see FIGURE 22). Discard old canister.
6. Remove O-ring from drain assembly using small screwdriver. Discard old O-ring.
• Allow humidifier to drain and disconnect power before servicing. Contact with electrical circuits can cause property damage, personal injury or death. Service and Troubleshooting must be performed by
qualified electrician.
7. With your finger, swirl the fluid/precipitate mixture in the bottom of the drain valve
• Service should be performed by a qualified HVAC technician.
reservoir (see FIGURE 22).
The following troubleshooting guide is intended to help diagnose and resolve general operational problems with the Steam Humidifier and optional
8. Using a sponge or paper towels, soak up the water in the reservoir. If necessary, use
INSPECT HUMIDIFIER WHEN SERVICING
a wet/dry vacuum to remove residue. Fan Pack . If a problem persists, call Aprilaire Tech Support toll-free at 1-800-334-6011 . Please be prepared to describe the exact nature of the problem .
• Check for loose electrode connections on the canister . Replace electrode wires if connection is loose . Change out electrode wires every 3 years For general operational problems, check to make sure humidifier is installed correctly .
9. Clean the inside of the drain port (where coil projects out) by gently swabbing with
(Part #4978) .
a bent cotton swab or other soft implement.
TABLE 6 – HUMIDIFIER TROUBLESHOOTING GUIDE
• Check system operation and inspect all plumbing connections and piping for signs of cracks or leaks .
10. Rinse the drain valve reservoir with clean water and vacuum as necessary.
• Inspect drain line to make sure it is not blocked and has constant downward slope . Clean or replace if necessary . Problem
11. Insert new O-ring (Part #5258) into slot in drain assembly. Dampen O-ring with
• Inspect steam hose to make sure it has no low spots and has constant upward slope from humidifier to dispersion tube in duct . If dispersion tube is
water before inserting canister. Do not use oil, grease, or any lubricant besides
mounted below humidifier, inspect drip tee and drain .
water.
• Clean and inspect condensate pump (if used) .
12. Make sure strainer is inserted into bottom of new canister.
TO REPLACE THE CANISTER
13. Insert new canister into drain assembly (see FIGURE 22).
14. Slip steam hose over top of canister and tighten hose clamp (see FIGURE 22).
1. Turn humidifier off .
2. Unit will go through drain cycle – 4 mins – and turn off when
15. Reconnect the electrode wires and water level probe wire tothe posts on top of the
complete .
canister (see Figure 20A and Figure 20B). Electrode wires are interchangeable and General operating problems .
Humidifier will not turn on or
can be placed on either of the two electrode posts on top of the canister. Ensure
3. Disconnect main electrical power to humidifier at the circuit breaker .
turn off .
connectors are fully seated.
4. Allow the unit to cool .
5. Remove front door .
ELECTRODE WIRE REPLACEMENT
6. Remove electrode wires, high water probe wire, steam hose and
canister . Remove front panel (see FIGURE 19).
1.
7. Remove O-ring from groove in drain assembly using a small screw
2. Remove side panel (see FIGURE 19).
driver .
3. Remove the electrode wires (see FIGURE 20A and FIGURE 20B).
8. Insect drain assembly and remove any debris – see TO CLEAN THE
DRAIN VALVE .
a. For units with one circuit board: Use needle nose pliers to pull the spade
connectors off spade terminals J8 and J10 on the circuit board.
9. Insert new O-ring into groove in drain assembly . (O-ring is provided Steam light does not turn on .
with Model 80 and Model 80LC canisters . ) Dampen O-ring with
b. For units with two circuit boards: Use needle nose pliers to pull the spade
water before inserting canister . Do not use oil, grease, or any
connectors off the spade terminals on the power relay.
lubricant besides water .
Water is leaking from
4. Ensure the two replacement electrode wires (Part #4978) have "O" shape connectors
humidifier .
10. Make sure strainer is inserted into bottom of new canister .
(see FIGURE 21B). Do not use replacement wires with "D" shape connectors (see
11. Insert canister into drain assembly . Position canister with label facing
FIGURE 21A).
outward .
5. Attach the new electrode wires (see FIGURE 20A and FIGURE 20B).
12. Reconnect steam hose and wires ensuring wires are fully seated .
a. For units with one circuit board: Use a pair of needle nose pliers to attach
13. Replace front door .
the spade connectors to the spade terminals J8 and J10 on the circuit board.
14. Restore electrical power to humidifier .
Water constantly runs down Electrode wires are interchangeable and can be placed on either of the two
drain .
terminals.
15. Turn humidifier On and verify green On/Off light is illuminated .
16. See Start-up procedure .
b. For units with two circuit boards: Use a pair of needle nose pliers to attach the
connectors to the spade terminals on the power relay. One wire, either one
17. Check for leaks .
but not both, must go through current-sensing toroid (see FIGURE 20A).
Electrode wires are interchangeable and can be placed on either of the two
Humidifier is filling and water
is flowing down drain but
terminals.
Drain light is not on .
Humidifier drains frequently .
26 English
Possible Cause
Field-wired terminal connections .
Internal connections .
No power to humidifier .
Humidifier not turned on .
No power to 24 volt control circuit .
Call for humidity not being
received .
Loose plumbing connections .
Hoses are blocked .
Drain hose is blocked .
Debris in drain valve preventing it
from closing .
O-ring in drain valve is not properly
seated in groove .
Water is flowing from fill cup
overflow port .
High static pressure in duct is
causing back pressure in canister .
High static pressure in steam line is
causing back pressure in canister .
Model 80LC canister used on water
that is too conductive .
NOTICE CAUTION
FIGURE 22: FILL & DRAIN SYSTEM AND CANISTER
Overflow
Action
Verify L1, N/L2 and ground connections are properly wired and appropriate voltage is
present .
Check HUMIDISTAT and (if used) FAN PACK terminal connections are tight and properly
wired .
Fill Valve
Fill
HUMIDISTAT terminals must be connected to an on/off device .
TO CLEAN THE DRAIN VALVE
Check wiring connections and settings on Accessory items such as high limit switch and
airflow proving switch .
1. Turn humidifier off .
Check electrode and high water probe connections on the top of the canister .
Supply
2. Unit will go through drain cycle – 4 mins – and turn off when
Make sure ribbon cable from membrane switch is securely plugged into control circuit Water
complete .
board .
Make sure black/white wire is attached to terminal that matches input voltage .
3. Disconnect main electrical power to humidifier at the circuit
FILL VALVE SERVICE
Check main power supply and switch .
breaker .
Ensure breaker is sized appropriately for the amperage draw .
4. Allow the unit to cool .
1. Disconnect water supply line from fill valve inlet (see
Check for proper voltage across L1 and N/L2 terminals .
FIGURE 22).
5. Remove front door .
Make sure front cover is attached to engage safety interlock switch . Press On/Off button .
6. Remove electrode wires, high water probe wire, steam hose and
2. Remove in-line strainer from the fill valve inlet port using a #8 or #10 sheet metal or
Make sure ribbon cable from membrane switch is not damaged and is securely plugged
canister .
wood screw with a minimum length of 0.5".
into the control circuit board .
7. With your finger swirl the fluid/precipitate mixture in the bottom of
Check fuse on PCB (replace with 5 amp slow burn fuse if necessary) .
3. Clean or replace in-line strainer (Part #4004).
the drain valve reservoir .
With humidifier energized, check that LED light D8 is energized on the circuit board . If
4. Reconnect water supply line to fill valve inlet (see Figure 22).
the LED is lit, replace the membrane switch, if not, replace the circuit board .
8. Using a sponge or paper towels soak up the water in the reservoir,
Check humidistat wiring and setting . (Do not leave ADHC in TEST mode . )
if necessary use a wet/dry vacuum to remove residue .
RESTORE UNIT TO SERVICE
Check wiring and settings of high RH limit switch and airflow proving switch .
9. Clean the inside of the drain port (where coil projects out) by
Replace side panel if removed (see FIGURE 19).
1.
Check water supply connection at fill valve inlet . Tighten as needed .
gently swabbing with a bent cotton swab or other soft implement .
Check internal hose clamp connections . Reposition clamps and tighten as needed .
2. Replace front panel (see FIGURE 19).
10. Rinse the drain valve reservoir with clean water and vacuum as
Check steam hose connection on top of canister . Tighten clamp as needed .
necessary .
3. Inspect drain hose to make sure it is not blocked and has constant downward slope.
Check internal hoses and eliminate kinks or blockage .
Clean or replace if necessary.
11. Replace canister, reconnect steam hose and wires ensuring wires
Make sure drain hose has constant downward slope and is not blocked .
are fully seated .
4. Inspect and clean condensate pump (if used).
Remove canister and clean debris from drain valve .
12. Replace front door .
5. Inspect steam hose to make sure it has no low spots and has constant upward slope
Remove canister and check O-ring for damage . Replace O-ring as necessary . Ensure
13. Restore electrical power to humidifier .
from humidifier to dispersion tube in duct. If dispersion tube is mounted below
O-ring is properly seated in its groove .
14. Turn humidifier On and verify green On/Off light is illuminated .
humidifier, inspect drip tee and drain trap.
Check internal hoses and eliminate kinks or blockage .
15. See Start-up procedure .
6. Restore main electrical power to humidifier at circuit breaker.
Make sure dispersion tube is not discharging into duct with greater than 2 . 0 in . w g static
16. Check for leaks .
pressure . 7. Turn humidifier on and verify green On/Off light is illuminated (see FIGURE 19).
Make sure dispersion tube tubelets are pointed up .
TO SERVICE THE FILL VALVE
8. Check system operation and inspect all plumbing connections and piping for signs
of cracks or leaks.
If water flow from the valve is restricted, disconnect the inlet fitting
Install a tee and drain trap in any low points in the steam line . See FIGURE 5 .
and remove in line strainer from the inlet port using a small screw .
Clean or replace strainer (Part #4004) .
Change to a Model 80 canister .
Steam Hose
Steam
Outlet
Water Level Probe
Electrodes
Canister
Drain Assembly
Drain Valve
Drain Cup
Drain
Tubelets
Dispersion
Tube in
Duct
90-1522
English 27