Defrost
Mode16:3216:3316:3716:34B1216:
3016:3316:32
Is the unit entering into defrost too often, or staying in defrost to long? Our
cases typically defrost every 6 to 8 hours as long as the evaporator sensor
is below defrost termination temperature of approximately 41°F. There is
also a defrost on demand feature that can supersede the normal defrost
interval as needed. (30 minute maximum defrost duration as well as a 30
minute minimum between defrosts)
Freezing Product
Adjust Temperature Control to a warmer set point. (1= Warmest 9=
Coldest)
Verify 10KOhm NTC sensor is reading properly.
Product Load
should also be a minimum of an inch off back wall to allow
supply air to circulate and not freeze product at the back wall. Some items
may need more clearance if they are sensitive to freezing, as supply air
temperature needs to get below freezing.
Warm Product
Adjust Temperature to a colder set point. (1= Warmest 9= Coldest)
Refrigerated Bottom Display Deck & Non-Refrigerated Shelves – if
equipped. Product Load Line – Only the display deck is the cold zone.
Cold Zone = only 7” of the interior floor near the rear of the case, and
extends down to
3” at the front of the case by the customer. Products above this load line
will be in an “unsafe” temperature zone and disrupt the cold zone causing it
to
struggle as well.
Verify 10KOhm NTC sensor is reading properly.
Check that the condenser air inlet and condenser air outlet are not
restricted.
Check that all evaporator fan motors and blades are working, as they
should.
Check that the condenser fan motor and blade are working, as they should.
Check that the evaporator is clear and not obstructed with ice or debris
Check TXV bulb installation is secure and insulated.
Check that superheat is between 8°F to 12°F
.
If equipped, check sight glass for flashing and/or low charge.
See Defrost Mode
Non-refrigerated
cases do not regulate internal temperature and may be
slightly higher than ambient temperature due to lighting in the unit or direct
sunlight.
Compressor Is Not
Operating
Check the control to see if the compressor run indicator is on, calling for
cooling.
Low-pressure cutout will keep compressor from engaging even if the
electronic unit controller is calling due to low charge.
Check for power in and out of pressure control as both Low and High side
pressure cutout will keep compressor from engaging.
Head Pressure Too High
Check that the condensing coil is not restricted.
Check that the condenser filter is not restricted.
Check that condenser fan motor is working and the condenser fan blade is
not damaged.
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