Airedale OptiChill FreeCool 500kW - 1365kW - Manual (Page 39)

Chillers OptiChill Freecool
Chillers
39
Technical Manual : 7197700 v1.2.0 02_2013
Controls
Temperature control Airedale recognises that all chiller applications are different but the OptiChill is based
upon Constant Supply Temperature.
The onboard microprocessor has the capability of satisfying either control requirement as
illustrated below. Using the Airedale Variable Supply Temperature control scheme,
energy savings are available when compared with previous schemes and that of the
Constant Supply Temperature application.
Variable Supply Temperature control schemes offer energy savings where the supply
water temperature is not critical to its operation.
Selection of the best application control scheme can be made via a soft switch in the
microprocessor during initial commissioning.
The microprocessor maintains the set supply Chilled Water temperature by sensing the
return and supply water temperatures and ambient air temperature to adjust the
compressor loading and water valve position as required.
Constant Supply
Temperature Control
Wa
te
r Te
m
pe
ratu
re
°C
6
7
8
9
1
3
1
(20%)
2
(40%)
3
(50%)
4
(60%)
5
(70%)
6
(80%)
7
(90%)
8
(100%)
10
11
12
13
14
Cooling Stages / Unit Capacity %
1 Return Water Temperature
2 Mean Value
3 Supply Water Temperature
4 Compressor Off