Led Indicators; User Adjustable Settings Chart; Setting Up The Controller - Bosch TW Series Installation, Operation And Maintenance Manual

TW Series Water to Water
pressing again will decrement the set point 1
degree for every push. Pressing and holding the
down button will decrement the set point at a
rate of 4 degrees per second.
• When pressed with the up arrow for 5- seconds,
the control will display the current temperature
scale (Fahrenheit or Celsius).
• Used to change the settings for: temperature
scale, dead band, test mode, initial delay,
compressor, pump, and malfunction settings.

LED Indicators

Mode
HEAT Red LED to indicate that the control is
in the HEATING mode
COOL Green LED to indicate that the control
is in the COOLING mode
AUTO Yellow LED to indicate that the control
is in AUTO mode
COM Red LED to indicate that pump(s) are
selected for continuous operation
CYC Red LED to indicate that pump(s) are
selected for cycling operation
SERVICE Red LED will turn steady on or blink to
indicate that a pressure switch has
opened

USER ADJUSTABLE SETTINGS CHART

Settings
TEMP SETTING
40-120
and Cooling
DIFFERENTIAL
1-10
MODE Heat, Cool, Auto,
Off
TEMP SCALE °, C °
F
PUMP MODE Con (continuous),
Cyc (cycle)
DEAD BAND ° F
1-6
AUTO CHANGE
55-85
OVER
TEST MODE De (delay), or
Nd (No delay)
COMPRESSOR Si (Single),
Du (Dual)
Revised 02-16
Indication
Range Default
°
F Heating
° °
F 1 F
Off
F
Von
° F
3
° F ° F
65
De
Si
User Adjustable Settings Chart | 19
Settings
LEAD LAG 0-14 Days
MALFUNCTION St (Steady),
Pu (Pulsing)

SETTING UP THE CONTROLLER

On unit power up the LED display will show the
software version, temperature differential setting
with the ability for the user to change it for ten
seconds then will display "OFF" and then finally
will display the control temperature of the fluid
being measured (entering fluid, leaving fluid, tank,
etc.) The default setting of the differential is 1°F
and can be adjusted from 1 – 10° F at start up.
The differential setting is the differential between
set point temperature and actual on\off
temperature of the machine.
For example:
Cooling set point = 45˚F
Differential = 1˚F
The heat pump will cycle on in cooling at 46˚F. If a
two stage machine, stage 2 will come on at 48˚F or
2˚F degrees above set point and one degree
differential. The unit will shut off at set point.
Heating set point = 120˚F
Differential = 1˚F
Stage one will come on at 119˚F and stage 2 will
come at 117˚F. Both stages will remain running
until set point is achieved. Stage 1 and stage 2 will
cycle on and off according to the lead\lag
programmed interval.
Whenever there is a demand for heating and cooling and
during the first stage of operation the
temperature isn't changing, then the control will
activate the second stage after a three minute delay from
the first stage activation. This logic will apply when the
control is powered up, on a power
interruption, when the mode function is set to OFF
and then back to either HEAT or COOL and when
switching from heating to cooling or vice versa in
the auto changeover mode.
Heating and cooling set points are adjusted by
selecting each mode on the key pad and then using
the up-down arrows to select the set point. Thus,
push cool mode button and use down arrow to 45˚F.
Push heat mode button and use up arrow to 120˚F.
The controller can be set to control heating only,
Range Default
0
St
6720220047 (2016/02)