TROUBLESHOOTING GUIDE
PROBLEM/SYMPTOM
PROBABLE CAUSE
REMEDY
Machine Will Not Start or
Shuts Down
(Panel RUN light out,
pumps off.)
No power to control panel
Check for building power failure. Check main circuit
breaker.
Control panel fuse blown
Examine circuits for ground or short.
Replace fuse.
Control panel main circuit breaker open
Close main circuit breaker.
Control panel switches not set correctly
Depress Stop button after safety shutdown.
Place capacity control and Cycle-Guard™ selections
in AUTO. and depress Start button.
Chilled water or condensing water pump
overloads or flow switches open
Check chilled water and condensing water pumps,
starters and valves.
Solution pump overloads open
Push overload reset button. Measure pump discharge
pressure to check for solution crystallization
(see Solution Decrystallization section on page 40).
Refrigerant pump overloads open
Push overload reset button.
Low temperature cutout
Depress Start button after chilled water has warmed
at least 7° F (4° C). Measure chilled water temperature.
Recalibrate or replace switch if temperature is above
set point. Check capacity control setting and operation
if temperature is below switch setting (see Check
Capacity Control Operation section on page 23).
High generator solution temperature
or pressure, high absorber pressure.
Check cooling water temperature and flow.
Check absorber pressure.
Leaving Chilled Water Temperature
Too High
(Machine running, chilled water
temperature above design.)
Steam control valve not open
Verify capacity control is positioned at AUTO.
Check capacity control operation per Initial Control
Checkout and Adjustment section, pages 22-24.
Set point too high
Reset temperature control in control panel.
Excessive cooling load (machine
at capacity)
Check for cause of excessive load.
Excessive chilled water flow
(above design)
Check pressure drop per selection data and reset flow.
Low condensing water flow (below design) Check pressure drop per selection data and reset flow.
High supply condensing water
temperature (above design)
Check cooling tower operation and temperature controls.
Low steam pressure (below design)
Raise to design per selection data.
Inadequate steam condensate drainage
(condensate backs up into tube bundle)
Check operation of steam traps, strainers, valves, and
condensate receivers.
Fouled tubes (poor heat transfer)
Clean tubes. Determine if water treatment is necessary.
Machine needs octyl alcohol
Check solution sample and add octyl alcohol if necessary
(see Adding Octyl Alcohol section on page 35).
Noncondensables in machine
Check absorber loss (see Absorber Loss Determination
section on page 31). If above 5° F (3° C), see Causes and
Remedies under Inadequate Purging (high absorber loss)
section on page 42.
Capacity control malfunction
Check calibration and operation of capacity controls (see
Check Capacity Control Operation section on page 23).
Solution crystallization
(solution flow blockage)
See Causes and Remedies under Solution Crystallization
on page 42.
Low refrigerant level
Check the low-level switch operation and check for low
condensing water temperature.
Cycle-Guard control malfunction
(low solution concentration)
Check refrigerant charge and thermoswitch calibration.
(See Refrigerant Charge Adjustment, Cycle-Guard Sys-
tem Operation and Thermoswitch Adjustment sections
on pages 35 and 36). Verify Cycle-Guard switch in AUTO.
Leaving Chilled Water
Temperature Too Low
(Machine running, chilled water
temperature below design.)
Set point too low
Reset temperature control in control panel.
Capacity control malfunction
Check calibration and operation of capacity control (see
Check Capacity Control Operation section on page 23).
Leaving Chilled Water Temperature
Fluctuates
(Machine running, capacity
control hunting.)
Chilled water flow or load cycling
Check chilled water system, controls and load.
Condensing water flow or temperature
cycling
Check condensing water temperature control and
cooling tower operation.
Steam pressure cycling
Check steam pressure control.
Inadequate steam condensate drainage
(condensate backs up into tube bundle)
Check operation of steam traps, strainer, valves,
and condensate receivers.
Capacity control malfunctions
Check calibration and operation of capacity control (see
Check Capacity Control Operation section on page 23).
41
Summary of Contents for 16JT Series
Page 11: ...Fig 10 Typical Wiring Diagram 11 ...
Page 12: ...Fig 10 Typical Wiring Diagram cont 12 ...
Page 13: ...Fig 11 Typical Control Wiring 13 ...
Page 43: ......