Specifications
        27 
Unit operates but windows 
have condensation 
Poor air distribution 
Ensure all exterior windows 
see 3-5 CFM/ft² of glass over 
their entire area 
Airflow across evaporator is 
too high. Coil only doing 
sensible cooling 
Check bypass damper 
operation. Ensure fully open or 
recalibrate in Service mode. 
Unit is undersized 
Re-evaluate unit sizing. Check 
for initially neglected sources 
of humidity 
Air and/or pool water 
temperature incorrect 
Reset controller setpoints to 
original design specifications 
Pool Water Heating 
 (PH and PV Models) 
Low water temperature rise 
Solenoid valve not opening 
Excessive water flow. This 
erodes the water heater and 
must be rectified. 
High water temperature rise  Insufficient water flow.  
Compressor runs for short 
periods and shuts off 
Conditions are being satisfied 
quickly 
Check register locations for 
short-circuiting of air 
Unit oversized 
Low Supply Air Temperature 
rise in Dehumidification Mode 
Too much airflow through unit. 
Balance the system airflow as 
directed in section 6.4 
High Supply Air Temperature 
rise in Dehumidification Mode 
Too little airflow through unit. 
Close bypass plugs until 
desired target range reached. 
Re-evaluate duct pressure 
losses to ensure they are 
within the parameters 
indicated on the unit 
nameplate. 
6.3. Microprocessor Troubleshooting 
Issue Possible Cause Remedy 
Communication fault 
Broken or loose wire between 
controller and IO board
Repair any damaged or loose 
wires. 
Corrosion on pins or terminals Clean pins and terminals
Defective IO board – LED is 
not on
Replace IO board 
Defective controller Replace controller
Sensor fault 
Sensor wires broken or 
shorted to ground 
Connect sensor directly to IO 
board. If it functions replace 
wire. 
Sensor reading outside design 
parameters 
Replace sensor 
Setpoint out of range 
Setpoint parameters are 
outside acceptable limits 
Reenter setpoint. Replace 
sensor if problem persists 
Emergency operation mode on 
Manually selected by user  Replace controller 










