York YCAQ10, Manual

Page: 59 / 99

FORM 150.40-NM20
59
YORK INTERNATIONAL
(YCHA120, 150, 175 & 200)
LWT COOLING RANGES (4 STAGE)
The user may use LWT control with a 4 stage chiller.
This can be accomplished by removing J8 (J8 OUT) or
Sw. 5 OFF on the Micro Logic Board which configures
the Micro for 4 stage control. The disadvantage of 4
stages is that we are cycling large tonnages each time
we turn a stage on or off. This could cause continuous cycling with the possibility of undesirable fluctuating leav-
ing water temperatures. The variation in LWT is prima-
rily due to the compressors cycling off and water tem-
perature rising before the anti-recycle timer times out to
allow the compressor to restart. The factory does not
recommend that the equipment be used in this manner.
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.0°F Setpoint plus 0.5°F
SWITCH = 0 Lag Compressor Stage 1 Setpoint plus 0.5°F Setpoint
COOLING RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 0.5°F
OF + 1.0°F Lead Compressor Stage 1 Setpoint minus 0.5°F Setpoint minus 1.0°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.2°F Setpoint plus 0.6°F
SWITCH = 1 Lag Compressor Stage 1 Setpoint plus 0.6°F Setpoint
COOLING RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 0.6°F
OF + 1.2°F Lead Compressor Stage 1 Setpoint minus 0.6°F Setpoint minus1.2°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.4°F Setpoint plus 0.7°F
SWITCH = 2 Lag Compressor Stage 1 Setpoint plus 0.7°F Setpoint
COOLI NG RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 0.7°F
OF + 1.4°F Lead Compressor Stage 1 Setpoint minus 0.7°F Setpoint minus 1.4°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.5°F Setpoint plus 0.8°F
SWITCH = 3 Lag Compressor Stage 1 Setpoint plus 0.7°F Setpoint
COOLING RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 0.8°F
OF + 1.5°F Lead Compressor Stage 1 Setpoint minus 0.7°F Setpoint minus 1.5°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.6°F Setpoint plus 0.8°F
SWITCH = 4 Lag Compressor Stage 1 Setpoint plus 0.8°F Setpoint
COOLING RANGE Lead Compr. Loader Staqe 2 SetPoint Setpoint minus 0.8°F
OF + 1.6°F Lead Compressor Stage 1 Setpoint minus 0.8°F Setpoint minus 1.6°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.8°F Setpoint plus 0.9°F
SWITCH = 5 Lag Compressor Stage 1 Setpoint plus 0.9°F Setpoint
COOLING RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 0.9°F
OF + 1.8°F Lead Compressor Stage 1 Setpoint minus 0.9 F Setpoint minus 1.8°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 1.9°F Setpoint plus 1.1°F
SWITCH = 6 Lag Compressor Stage 1 Setpoint plus 1.1°F Setpoint
COOLING RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 1.1°F
OF + 1.9°F Lead Compressor Stage 1 Setpoint minus 1.0°F Setpoint minus 1.9°F
STAGE ON OFF
COOLING RANGE Lag Compr. Loader Stage 2 Setpoint plus 2.0°F Setpoint plus 1.0°F
SWITCH = 7 Lag Compressor Stage 1 Setpoint plus 1.0°F Setpoint
COOLING RANGE Lead Compr. Loader Stage 2 Setpoint Setpoint minus 1.0°F
OF + 2.0°F Lead Compressor Stage 1 Setpoint minus 1.0°F Setpoint minus 2.0°F