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C l i m a t e M a s t e r W a t e r- S o u r c e H e a t P u m p s
C L I M A T E M A S T E R W A T E R - S O U R C E H E A T P U M P S
Tr a n q u i l i t y
®
2 0 ( T S ) S e r i e s
R e v. : 0 6 / 1 7 / 1 5
T
o
‘ESD’
on
DXM
T
o
‘R’
on
DXM
ESD S
igna
l
(fi
e
l
d
in
p
ut
)
The ECM motor includes “soft start” and “ramp down”
features. The soft start feature is a gentle increase of
motor rpm at blower start up. This creates a much quieter
blower start cycle.
The ramp down feature allows the blower to slowly
decrease rpm to a full stop at the end of each blower
cycle. This creates a much quieter end to each blower
cycle and adds overall unit effi ciency.
The ramp down feature may be eliminated during an
ESD (Emergency Shut Down) situation when using a DXM
unit controller. A DPDT relay is required to break the line
voltage to the ECM motor during ESD. This relay can be
wired as shown below to eliminate the ramp down (and
operation) of the ECM blower motor.
ECM Blower Control
When dehumidifi cation is enabled there is a reduction
in airfl ow in cooling to increase the moisture removal of
the heat pump. Consult submittal data or specifi cations
catalog for the specifi c unit series and model to correlate
speed tap to airfl ow in CFM. The dehumidifi cation mode
can be enabled in two ways.
1.
Constant Dehumidifi cation Mode:
When the
dehumidifi cation mode is selected (via DIP switch
or jumper setting), the ECM motor will operatewith
a multiplier applied to the cooling CFM settings
(approx. 20-25% lower airfl ow). Any time the unit
is running in the cooling mode, it will operate at
the lower airfl ow to improve latent capacity. The
“DEHUM” LED will be illuminated at all times.
Heating airfl ow is not affected
Note: Do not select
dehumidifi cation mode if cooling setting is tap 1.
2.
Automatic (Humidistat-controlled) Dehumidifi cation
Mode:
When the dehumidifi cation mode is selected
(via DIP switch or jumper setting AND a humidistat is
connected to terminal DH(version II) or HUM (version
I), the cooling airfl ow will only be reduced when the
humidistat senses that additional dehumidifi cation is
required. The DH (or HUM) terminal is reverse logic.
Therefore, a humidistat (not dehumidistat) is required.
The “DEHUM” LED will be illuminated only when
the humidistat is calling for dehumidifi cation mode.
Heating airfl ow is not affected.
Note: Do not select
dehumidifi cation mode if cooling setting is tap 1.
