Alto-Shaam quickchiller QC-50, Руководство по установке и обслуживанию

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#8400 Installation & Maintenance Manual
- Pg. 8
2 . 0 — C o n t r o l S e t - U p a n d O p e r a t i o n
Ta b l e 2 . 4 . 1
C O N T R O L M O D E O V E RV I E W
Mode Operation Description
Refrigeration is controlled only by the food probe(s). Refrigeration
continues until all food probes achieve chill setpoint temperature,
whereupon the control automatically enters HOLD Mode.
Refrigeration is controlled by chill time entered and the cabinet air
sensor. While chilling, the cabinet air temperature may become exces-
sively cold prior to chill time expiration. The cabinet air sensor will then
cycle the refrigeration system OFF and ON, at cabinet air temperatures of
15°F (-9°C) and 20°F (-7°C) respectfully, until chill time expiration. The
control automatically enters Hold Mode upon chill time expiration.
Refrigeration is controlled by the cabinet air sensor only.
Only the evaporator coil defrost heaters are operational with a 20
minute time limit. A coil mounted defrost heater terminator switch
(thermal) limits the coil temperature to 60 °F (15°C) maximum until 20
minutes expire. Auto Defrost occurs automatically after six (6) hours
of continuous evaporator fan operation. The six hour "count-up" is
overridden in either Chill Mode.
Can only be selected in the HOLD Mode. See Auto Defrost for
operation. Upon completion of a manual defrost, the Quickchiller will
not automatically default to the Hold Mode. Control mode selection is
required.
NOTE: For optimum performance, utilize Manual Defrost at the start and end of each service day.
Ta b l e 2 . 4 . 2
E VA P O R AT O R FA N , D O O R H E AT E R & C O N D E N S I N G U N I T O P E R AT I O N
OPERATION SPECIFICS
Evaporator
✓
Controlled by door switch and evaporator coil mounted for terminator switch (thermal).
Fan(s)
✓
OFF when door is opened.
✓
OFF with coil temperature above 60°F (15°C).
✓
ON with coil temperature below 30°F (-1°C).
Door Heater
✓
ON and OFF with evaporator fan(s).
Condensing
Unit(s)
✓
Controlled by a low pressure switch (cut-out @ 2 PSIG, cut-in @ 18 PSIG).
✓
Upon control mode satisfaction, the liquid line solenoid valve closes to begin a
low side pump-down with condensing unit shutoff at 2 PSIG.
✓
Upon call for refrigeration, the liquid line solenoid valve opens which increases
low side pressure to condensing unit start at 18 PSIG. Refer to Section 2.7, Shut-
Down Procedure for additional details.
N O T E : T h e RT D s e n s o r ( s ) m o u n t e d t o t h e e v a p o r a t o r c o i l s e r v e s n o c o n t r o l l i n g
p u r p o s e a n d i s f o r d i s p l a y i n g c o i l t e m p e r a t u r e f o r r e f e r e n c e o n l y.
Auto Chill
Timed Chill
Hold
Auto Defrost
Manual Defrost