Aprilaire 800 Installation & Maintenance Instructions Manual page 22

CHeCkInG SySTeM oPeRaTIon & TRoUbleSHooTInG
Table 5 – Troubleshooting Guide (continued)
Problem
Water is flowing down drain
while humidifier is making
steam (Steam light illuminated
green or yellow) .
Humidifier makes gurgling
sound .
Fill valve makes banging
sound .
Humidifier will not fill .
Humidifier fills constantly .
Humidifier will not drain .
Water in duct from dispersion
tube .
Service light flashing red
before end of humidification
season .
Yellow steam light .
Humidifier is not satisfying
demand .
Excess humidity .
Solid red fill light .
Solid red service light .
22
Possible Cause
O-ring is not properly inserted .
Excess condensation in steam hose .
Water hammer from line pressure .
Saddle valve not open or pipe not
pierced . .
Malfunctioning fill valve .
Hoses are blocked .
Internal wiring connections .
Debris in drain valve blocking outlet port .
Malfunctioning drain valve .
Dispersion tube installed incorrectly .
Impurities in steam hose or pipe causing
foaming .
Canister full of mineral deposits .
Humidifier runs in short cycles (does not
reach capacity) .
Humidifier operating below rated
capacity . (Normal operation for systems
plumbed to low conductivity water and
systems that operate for short cycles .)
Control setting is too low .
Control mounted in wrong location .
Short run times .
Humidifier capacity limited by input
power (120V) .
Control setting is too high .
Control mounted in wrong location .
Fill valve has been filling for 40 minutes .
High static pressure in the duct is causing
back pressure in the duct .
Unit senses current 120% above nominal
and cannot lower amperage after three
drain cycles .
(ConTInUeD)
action
Remove canister and make sure O-ring is seated in groove in drain valve .
Make sure steam hose has constant downward slope to humidifier or to tees
and traps in low spots of hose .
If hard pipe is used for dispersion system, make sure it is insulated .
Make sure water supply line does not contact ductwork .
Install shock arrestor .
Install section of 1/4" braided fill line . Conform to local codes .
If water supply pressure is greater that 120 psi, install pressure reducer .
Make sure saddle valve is properly installed and the valve is open .
Check valve function using Test Mode .
Check internal hoses and eliminate kinks or blockage .
Make sure blue/white wire jumpers (2) connecting Control PCB and Current Sensing
PCB are secure and properly oriented . See Wiring diagram figure 10, 11 or 12 .
Remove canister and clean debris from drain valve .
Check valve function using Test Mode .
Install dispersion tube with tublets facing straight up .
Rinse canister, fill hose and fill cup with clean water .
Remove canister and rinse with clean water .
Plumb humidifier to filtered water .
Plumb humidifier to softened water .
Use blower activation feature on ADHC or run constant HVAC fan .
Plumb humidifier to softened water .
Use blower activation feature on ADHC or run constant HVAC fan .
Operate humidifier on 240 volts .
To determine operating current, attach clamp-on ammeter to one of the
electrode wires on top of canister .
Dissolve one tablespoon of salt into one cup of hot water . Add to the fill cup in
1/4 cup increments until unit operates properly . Yellow steam light will clear
after first fill valve cycle at nominal amperage operation . Do not over salt .
System will drain and refill with clean water due to over current fault .
Adjust control to higher setting .
See Installation Instructions with control for correct mounting location .
Use blower activation feature on ADHC or run constant HVAC fan .
Operate humidifier on 240 volts .
Increase capacity to 16 .0 amps . Make sure breaker is appropriately sized .
Adjust control to lower setting .
See Installation Instructions with control for correct mounting location .
Make sure high water pin electrode wire is securely installed .
Make sure dispersion tube is not discharging into a duct with greater than 2 .0
in .wg . static pressure .
Make sure dispersion tube tubelets are pointed up .
Rinse canister to remove mineral deposits or install a new canister .