Bosch EP015 Installation And Maintenance Manual page 8

8 EP Series
Water side freeze protection sensor,
mounted close to condensing water coil,
monitors refrigerant temperature between
condensing water coil and thermal expansion
valve. If temperature drops below or remains
at freeze limit trip for 30 seconds, the
controller will shut down the compressor
and enter into a soft lockout condition. The
default freeze limit trip is 30°F, however this
can be changed to 15°F by cutting the R30 or
Freeze1 resistor located on top of DIP switch
SW1. Refer to Figure #5, item [3] for resistor
location.
If unit is employing a fresh water system (no
anti-freeze protection), it is extremely
important to have the Freeze1 R30 resistor
set to 30°F in order to shut down the unit at
the appropriate leaving water temperature
and protect your heat pump from freezing if a
freeze sensor is included.
Evaporator freeze protection sensor,
mounted between the thermal expansion
device and the evaporator, monitors
refrigerant temperature between the
evaporator coil and thermal expansion valve.
If temperature drops below or remains at
freeze limit trip for 30 seconds, the controller
will shut down the compressor and enter into
a soft lockout condition. The default freeze
limit trip is 30°F.
The condensate overflow protection sensor
is located in the drain pan of the unit and
connected to the 'COND' terminal on the
UPM board.
8733922168
Safety Devices and the UPM Controller
UPM Board Factory Default Settings
Temp
Lockout
Reset
Alarm
Test
UPM DIP SWITCH DEFAULT POSITION
lockout
reset
alarm
test
Caution
Subject to change without prior notice
30°F
2
Y
PULSE
NO
4 2
R Y
Cont pulse
yes no
Figure #6
If freeze protection sensor is not installed, a
jumper between freeze contacts must be installed
on the UPM board otherwise unit will not start.
Revised 12-13