Bosch LM Split CS Series User Manual

28 | Troubleshooting LM Series Heat Pump
LM Series Heat Pump8 733 905 315 (2013/9) Subject to change without prior notice
YELLOW "ALERT”
FLASH CODE 5
Open Circuit 1. Outdoor unit power disconnect is open
2. Compressor circuit breaker or fuse(s) is open
3. Compressor contactor has failed open
• Check compressor contactor wiring and connectors
• Check for compressor contactor failure (burned,
pitted or open)
• Check wiring and connectors between supply and
compressor
• Check for low pilot voltage at compressor contactor
coil
4. High pressure switch is open and requires manual reset
5. Open circuit in compressor supply wiring or
connections
6. Unusually long compressor protector reset time due to
extreme ambient temperature
7. Compressor windings are damaged
• Check compressor motor winding resistance
YELLOW "ALERT”
FLASH CODE 6
Open Start Circuit
Current only in run
circuit
1. Run capacitor has failed (may not be bad, verify)
2. Open circuit in compressor start wiring or connections
• Check wiring and connectors between supply and
the compressor "S'" terminal
3. Compressor start winding is damaged
• Check compressor motor winding resistance
YELLOW "ALERT”
FLASH CODE 7
Open Run Circuit
Current only in start
circuit
1. Open circuit in compressor run wiring or connections
• Check wiring and connectors between supply and
the compressor "R” terminal
2. Compressor run winding is damaged
• Check compressor motor winding resistance
YELLOW "ALERT"
FLASH CODE 8
Welded Contactor
Compressor always
runs
1. Compressor contactor has failed closed
2. Thermostat demand signal not connected to module
YELLOW "ALERT"
FLASH CODE 9
Low Voltage
Control circuit <
17VAC
1. Control circuit transformer is overloaded
2. Low line voltage (contact utility if voltage at disconnect
is low)
• Check wiring connections Flash Code number
corresponds to a number of LED flashes, followed
by a pause and then repeated. TRIP and ALERT LEDs
flashing at same time means control circuit voltage
is too low for operation
Comfort Alert Module -Flash Codes
Status LED
Status LED
Description
Status LED Troubleshooting Information Solution

Bosch LM Split CS Series Specifications

General

Brand	Bosch
Model	LM Split CS Series
Category	Heat Pump
Language	English