NANO Precision NPC 015, Service Manual

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The data inside this manual are not binding and they can be modified by the manufacturer without notice. All rights reserved.
NPC 015 TO 230
7.12.7 Displaying t he operating hou rs o f loads “C1Hr - C2Hr - PF Hr”
1. Press
*
button to enter Function menu.
2. Press
(
or
'
button until the Label of a single load appears in the bottom of the display: C1Hr (operating hours of compressor
1), C2Hr (operating hours of compressor 2), PFHr (operating hours of water pump and of outlet fan).
The operating hours will appear in the top of the display.
3. The icon will be lit.
7.12. 7. 4 Reset o f th e load operatin g h ours
1. Press
*
button to enter Function menu.
2. Press
(
or
'
button until the Label of a single load appears in the bottom of the display ( C1Hr , C2Hr only 201÷351 units,
PFHr ) and the operating hours appear in the top of the display.
3. Press
-
button for 3 seconds: in the top of the display it will appear “0”. It indicates that the reset has happened.
4. To exit Function menu, press
*
button or wait for time out (15 seconds).
5. For the other loads repeat the operations from point 2. to point 4.
7 . 1 3 O t h e r f u n c t i o n s b y k e y b o a r d
7.13.1 How to display th e Set Poin t
Press and release
-
button.
In the bottom part of the display it appears SetC (chiller set).
7.13.2 How to modify the Set Po int
1. Press
-
button for 5 seconds at least.
2. The set point will flash.
3. Use
(
or
'
button to modify the set point value.
4. To store the new set point value press
-
button or wait for time out to exit programming procedure.
7 . 1 4 C o m p r e s s o r s u n l o a d i n g f u n c t i o n
This procedure is necessary when sudden peaks in cooling demand occur, for instance if the machine is restarted after a long period of inactivity.
Under these conditions the evaporator inlet water temperature might be so high as to require a cooling delivery in excess of system capacity.
The consequent system overload would require the start-up of all the compressors at once, which would be forced to operate in near-limit
conditions.
The overburdened compressors would thus be subject to dangerous overheating which would cause the activation of the thermal protections, or
the pressure of the refrigerant gas could reach alarm levels which would cause the machine to shut down.
This function enables the machine to run (through the switch-off or capacity step operation of the compressors) even when the temperature of the
water at the evaporator’s inlet is high (summer start-up with hot water accumulation), preventing the possible triggering of high pressure alarms.
It is not present in one compressor units.
The following messages will flash on the display:
AEUn = evaporator unloading function
ACUn = condensation unloading function
7 . 1 5 P r o b e k e y
In this chapter are indicated the probes BEWOT , BTWOT , BCP1 and BAT1 , for their positioning consult the refrigerant drawing.
Their description is indicated in the following table:
Name in the manual Borne name Description
-BEWOT PB1 EVAPORATOR WATER OUTLET TEMPERATURE PROBE
-BTWOT PB2 TANK WATER OUTLET TEMPERATURE PROBE
-BCP1 PB3 CONDENSING PRESSURE TRANSDUCER (only with electronic regulation)
-BAT1 PB4 AMBIENT AIR TEMPERATURE PROBE (Only with antifreeze protection
function)