Bard MC4000 SERIES, Installation Instructions & Replacement Parts List

Page: 12 / 40

Manual 2100-563
Page
12 of 40
3
rd
cooling set point is 2F (default setting, user selectable
2-3F) warmer than Stage 2. On a call for 3
rd
Stage
cooling the blower of the lag unit is turned on (if not
already on – See Blower Operation), and the Stage 3
LED will blink for 10-seconds before going solid, and
the lag unit economizer will operate if the outdoor
temperature and humidity conditions are below the set
point of the economizer control. If outdoor conditions
are not acceptable for free cooling the compressor will
automatically operate instead of the economizer.
4
th
cooling set point is 2F (default setting, user selectable
2-3F) warmer than Stage 3. On a call for 4th Stage
cooling the lag unit economizer will close and the
compressor will operate. If the compressor is already
running from 3
rd
stage cooling call due to outdoor
conditions being outside of free cooling range no action
occurs at 2
nd stage set point.
3. 1-Stage Compressor Units with Newer
ECONWMT Economizers (See Note A)
1
st
stage cooling set point is the setting (SP) input into
the controller. Factory default is 77F (25C). On a call for
cooling the blower of the lead unit will come on
immediately (if not already on – See Blower Operation),
and the Stage 1 LED will blink for 10-seconds before
going solid, at which time the lead unit Y1 cooling
output turns on. If the outdoor temperature and humidity
conditions are below the set point of the economizer
control the lead unit economizer will operate instead of
the compressor. If outdoor conditions are not acceptable
for free cooling the compressor will automatically
operate instead of the economizer.
2
nd
cooling set point is 4F (default setting, user
selectable 2-6F) warmer than Stage 1. On a call for 2 nd
stage cooling the lead unit Y2 cooling output turns on. If
the outdoor temperature and humidity conditions are
below the set point of the economizer control the lead
unit economizer will continue to operate, and the
compressor will operate. If the compressor is already
operating on 1
st
stage cooling because outside free
cooling range no action occurs at 2
nd
cooling set point.
3 rd cooling set point is 2F (default setting, user selectable
2-3F) warmer than Stage 2. On a call for 3
rd
Stage
cooling the blower of the lag unit will come on
immediately (if not already on – See Blower Operation),
and the Stage 3 LED will blink for 10-seconds before
going solid, at which time the lag unit Y1 cooling output
turns on. The lag unit economizer will operate if the
outdoor temperature and humidity conditions are below
the set point of the economizer control. If outdoor
conditions are not acceptable for free cooling the
compressor will automatically operate instead of the
economizer.
4
th
cooling set point is 2F (default setting, user selectable
2-3F) warmer than Stage 3. On a call for 4
th
Stage
cooling the lag unit Y2 cooling output turns on
activating the lag unit compressor. If the outdoor
temperature and humidity conditions are below the set
point of the economizer control the lag unit economizer
will continue to operate. If the compressor is already
operating on 3
rd
stage cooling because outside free
cooling range no action occurs at 4
th
cooling set point.
4. 2-Stage Compressor Units with Older EIFM
Economizers
1 st stage cooling set point is the setting (SP) input into
the controller. Factory default is 77F (25C). On a call for
cooling the blower of the lead unit will come on
immediately (if not already on – See Blower Operation),
and the Stage 1 LED will blink for 10-seconds before
going solid, at which time the lead unit Y1 cooling
output turns on. If the outdoor temperature and humidity
conditions are below the set point of the economizer
control the lead unit economizer will operate instead of
the compressor. If outdoor conditions are not acceptable
for free cooling the compressor will automatically
operate on compressor Stage 1 partial capacity instead of
the economizer.
2
nd
cooling set point is 4F (default setting, user
selectable 2-6F) warmer than Stage 1. On a call for 2
nd
stage cooling the lead unit Y2 cooling output turns on, at
which time the lead unit compressor will operate on
compressor Stage 2 full capacity. If the compressor is
already operating on Stage 1 partial capacity because
outside free cooling range the compressor will switch to
compressor Stage 2 full capacity.
3
rd
cooling set point is 2F (default setting, user selectable
2-3F) warmer than Stage 2. On a call for 3
rd
Stage
cooling the blower of the lag unit will come on
immediately (if not already on – See Blower Operation),
and the Stage 3 LED will blink for 10-seconds before
going solid. The lag unit economizer will operate if the
outdoor temperature and humidity conditions are below
the set point of the economizer control. If outdoor
conditions are not acceptable for free cooling the
compressor will automatically operate on compressor
Stage 1 partial capacity instead of the economizer.
4 th cooling set point is 2F (default setting, user selectable
2-3F) warmer than Stage 3. On a call for 4
th
Stage
cooling the lag unit Y2 cooling output turns on, at which
time the lag unit compressor will operate on compressor
Stage 2 full capacity. If the compressor is already
operating on Stage 1 partial capacity because outside
free cooling range the compressor will switch to
compressor Stage 2 full capacity.