Forma Scientific, Inc.___________________________________________________Service
7-8
Symptom Possible Cause
No Power Light on Monitor. • Power line cord disconnected.
• Circuit breaker tripped/open.
• Main power switch OFF.
• Pin-connector not plugged
into the monitor board.
• Fuse open on Temp Control board
• Main fuse(s) open.
Chamber Temp Deviates from Set
Point
• Too much warm product added
• Door open too long
• Insufficient voltage
• Inadequate air circulation
• Calibration
• Dirty condenser
• High Ambient Temperatures
Too Much Frost Build-Up • Leaking or damaged door gasket
Freezer not Being Refrigerated
(unit is receiving power)
• Compressor thermal overload open
• Loss of refrigerant in either system
• Defective compressor(s)
• Defective temp control
• Defective high pressure cut-off
• Low stage compressor locked up
• Main fuse(s) open
Display Problems in General • Defective monitor board
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