Specifications

Table 45 -- Humidi-MiZer TM Service Analysis
PROBLEM
Subcooling Reheat Mode
Will Not Activate.
Hot Gas Reheat Mode
Will Not Activate.
No Dehumidification Demand.
RH1 Valve Operation.
RH2 Valve Operation.
(NOTE: Normally Closed
When Deenergized)
Low Latent Capacity in Subcooling or Hot
Gas Reheat Modes.
Low Sensible Capacity
in Normal Cool or
Subcooling Reheat Modes.
Low Suction Pressure and High
Superheat During Normal Cool Mode.
Low Suction Pressure
RH2 Valve Cycling On/Off.
Circuit B Will Not Operate With
Circuit A Off.
LEGEND
CV -- Cooling Valve
RH -- Relative Humidity
CAUSE
General cooling mode problem
No dehumidification demand.
Circuit RH1 valve is not open
General cooling mode probIem
No dehumidification demand.
Circuit RH1 valve is not open
Circuit RH2 valve is not open
Outdoor temperature too Iow.
Relative humidity setpoint is too tow --
Humidistat
Relative humidity setpoint is too tow --
RH sensor
Software configuration error for accessory humi-
distat
Software configuration error for accessory
humidity sensor.
No humidity signal
No 24V signal to input terminals
Solenoid colt burnout.
Stuck valve
No 24V signal to input terminals
Solenoid coit burnout.
Stuck valve
RH1 valve open or leaking.
RH2 valve open or leaking. See RH2 Valve Operation, above
General cooling mode problem
RH2 valve open or leaking.
General cooling mode probtem
Hot Gas Reheat mode Iow suction pressure
Iimit
Normal operation Motormaster outdoor fan con-
trol requires operation of circuit A
REMEDY
See Cooting Service Analysis (Table 44).
See No Dehumidification Demand, below.
See RH1 Valve Operation, below
See Cooting Service Analysis (Table 44).
See No Dehumidification Demand, below.
See RH1 Valve Operation, beIow
See RH2 Valve Operation, below
Check Reheat2 Circuit Limit Temperatures (Configuration;,
HMZR >RA LO and RB.LO)using ComfortLink TM Scrolling Marquee.
Check/reduce setting on accessory humidistat
Check Space RH Setpoint (Setpoints ,'-RH.SP)
using ComfortLink Scrolling Marquee.
Check Space Humidity Switch (Configuration >UNIT >RH.SW) using
ComfortLink Scrolling Marquee
Check RH Sensor on OAQ Input (Configuration >UNIT >RH S) using
ComfortLink ScrolIing Marquee
Check wiring Check humidistat or humidity sensor
Check using Cool >Reheat1 Valve Test (Service Test >HMZR >CRC)
using ComfortLink Scrolling Marquee.
Check Wiring
Check transformer and circuit beaker or fuses
Check continuous over-voltage is less than 10%
Check under-voltage is less than 15%
Check for missing coit assembly parts.
Check for damaged valve enclosing tube.
Reptace valve. Replace fitter drier
Check using Coot >Reheat1 Vatve Test (Service Test >HMZR
>RHV.A or RHV.B) using ComfortLink Scrolling Marquee
Check MBE relay output
Check wiring.
Check transformer and circuit breaker or fuses
Check continuous over-voltage is less than 10%
Check under-voltage is less than 15%
Check for missing coil assembly parts.
Check for damaged valve enclosing tube.
RepIace valve. Replace filter drier
See RH1 Valve Operation, above
See Cooting Service Analysis (Table 44).
See RH2 Valve Operation, above
See CooIing Service Analysis (Table 44).
NormaI Operation During Mixed Circuit Subcooling and Hot Gas
Reheat Modes at Lower Outdoor Temperatures.
None
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