Bosch CE Series - User Manual

Questions and Answers

J
Juan OwenAug 2, 2025
What to do if my Bosch Heat Pump unit turns off on high pressure control?
- M
  Michael HunterAug 3, 2025
  If your Bosch Heat Pump unit turns off due to high pressure, it could be caused by several factors. In cooling mode, check for lack of water flow, inadequate water flow, water temperature that is too warm, or a scaled or plugged condenser. In heating mode, check for lack of air flow, an inoperative blower, a clogged filter, or restrictions in the duct work. Also, the unit may be overcharged with refrigerant. If so, reclaim the refrigerant, evacuate the system, and recharge it with the factory-recommended amount. Finally, check for a defective or improperly calibrated high-pressure switch.
D
dhernandezAug 8, 2025
What to do if my Bosch CE Heat Pump turns off on low pressure control?
- W
  Walter BridgesAug 8, 2025
  If your Bosch Heat Pump unit turns off on low pressure control, it may be due to suction pressure being too low. In cooling mode, check for lack of or inadequate airflow, or entering air temperature that is too cold. Ensure the blower is operative, the filter isn't clogged, and there are no ductwork restrictions. In heating mode, check for lack of or inadequate water flow, or entering water temperature that is too cold, and inspect for a scaled or plugged condenser. Additionally, the unit might be low on refrigerant; check for leaks, repair them, evacuate the system, and recharge with the factory-recommended amount. Finally, check for a defective or improperly calibrated low-pressure switch.
V
vkaneAug 18, 2025
Why does the blower operate but the compressor not on my Bosch CE Heat Pump?
- B
  Bradley ScottAug 18, 2025
  If your Bosch Heat Pump blower operates but the compressor doesn't, first check the thermostat's settings, calibration, and wiring. Then, inspect the wiring at the compressor, capacitor, or contactor for loose or broken wires. Check the UPM board red default L.E.D. for a Blink Code. If the compressor is cool and the overload won't reset, replace the compressor. If the compressor motor is grounded (internal winding grounded to the compressor shell), replace the compressor and install a suction filter dryer if there was a compressor burnout. Finally, after the compressor has cooled, check the continuity of the compressor windings; if they're open, replace the compressor.
D
Daniel BaldwinAug 23, 2025
Why does my Bosch CE unit short cycle?
- K
  Karen MontesAug 23, 2025
  If your Bosch Heat Pump is short cycling, the unit might be oversized, so recalculate the heating and cooling loads. The thermostat could be installed near a supply air grill; if so, relocate it and readjust the heat anticipator. Also, check the wiring and controls for a defective or improperly calibrated low-pressure switch.
L
Lisa MooreOct 28, 2025
How to troubleshoot a Bosch Heat Pump that does not run?
- J
  James ParkerOct 28, 2025
  If your entire Bosch Heat Pump unit isn't running, first ensure the power supply is on and the disconnect is closed. If that's not the issue, check for a blown fuse and replace it or reset the circuit breaker, ensuring you use the correct fuses. If the voltage supply is low (below the minimum specified on the unit's data plate), contact your local power company. Finally, the thermostat could be the problem. Set the fan to “ON”—it should run. Set the thermostat to “COOL” at the lowest temperature; the unit should cool. Set it to “HEAT” at the highest temperature; the unit should heat. If nothing happens, the thermostat may be miswired or faulty. Verify 24 volts at the condensing unit's low voltage terminal strip between “R” and “C”, “Y” and “C”, and “O” and “C”. If the blower doesn't work, ...
R
Rita CochranNov 12, 2025
How to fix insufficient cooling or heating in my Bosch CE?
- A
  alexismurrayNov 12, 2025
  If your Bosch Heat Pump isn't cooling or heating sufficiently, it could be undersized; recalculate heating and cooling loads, and consider adding insulation and shading. Check for leaks in ductwork or ambient air entering through doors or windows. Ensure adequate airflow and proper air distribution, and replace any dirty filters. Low refrigerant charge can also cause inefficient operation. Check the compressor for defects; if the discharge is too low and suction pressure is too high, the compressor isn't pumping properly and should be replaced. A defective reversing valve can cause refrigerant bypass, so replace it if necessary. Compare unit operating pressures to the pressure/temperature chart. Check the TXV for restrictions or defects, replacing it if needed. Finally, the refrigerant sys...

Summary

Model Nomenclature

Initial Inspection

General Description

Provides an overview of the CE Series Water-to-Air Heat Pumps' performance, efficiency, and safety features.

Installation

Mounting Vertically

Details on how to properly mount vertical units, including leveling and vibration isolation.

Mounting Horizontaly

Instructions for suspending horizontal units from ceilings using hanger bracket kits and ensuring secure anchoring.

Location

Guidance on selecting an appropriate indoor location for the unit, ensuring access and proper ventilation.

Hanging Bracket Kit

Installation instructions

Step-by-step guide for attaching hanging brackets to horizontal units for suspended mounting.

Condensate Drain

Duct System

Guidelines for connecting supply and return air ducts, including insulation recommendations and avoiding direct air paths.

Piping

Electrical

Field wiring requirements, compliance with codes, voltage range verification, and circuit protection.

Thermostat Connections

ECM Interface Board

Details the ECM Interface Board, its terminal block, and LED indicators for status and troubleshooting.

Safety Devices and the UPM Controller

UPM Board Dry Contacts

Explains that UPM Board's dry contacts are normally open (NO) by default, used for safety interlocks.

Water Side Freeze Protection

Describes the water side freeze protection sensor, its function, and adjustable trip points for unit shutdown.

UPM Board Factory Default Settings

Lists the default temperature, lockout, reset, alarm, and test settings for the UPM Board.

UPM DIP SWITCH DEFAULT POSITION

UPM Board Features

Covers UPM Board timers like anti-short cycle, random start, bypass timers, and protection mechanisms.

Malfunction Output

Explains the malfunction output (dry contact) and its settings for indicating faults (constant or pulse).

Display Output

Describes the display output used for the Unit Diagnostic Display (UDD) during lockout alarms.

Test Dip Switch

Details the function of the test dip switch for reducing time delays during troubleshooting.

Freeze Sensor

Explains the freeze sensor input, configurable points, and its role in soft lockout and compressor shutdown.

L.E.D. FAULT INDICATION

Intelligent Reset

Describes the intelligent reset process, fault indication during delay, and conditions for hard lockout.

Lockout Reset

Explains how to reset a hard lockout condition by cycling power or thermostat settings.

UPM Sequence of Operation

Electric Heater Package Option

Heater Package Compatibility

Provides compatibility information and electrical data for various heater package sizes with CE Series units.

Heat Recovery Package

Typical Connection Piping (HRP)

Details the steps for preparing a water tank and connecting piping for the Heat Recovery Package.

HR Water Piping

Specifies requirements for hot water piping size, insulation, and isolation valves for the HRP.

Water Tank Refill

Initial Start-Up

Steps for initial startup of the heat pump and heat recovery system, verifying operation in cooling mode.

Hot Gas Reheat (HGRH)

Explains the Hot Gas Reheat option for dehumidification and its control requirements.

Sequence of Operation

Cooling Mode

Describes the sequence of operation for cooling mode, including fan and compressor staging.

Heating Mode

Details the heating mode operation, including auxiliary heat and compressor sequencing.

Application Considerations

Provides guidance on various application scenarios, including well water systems.

Installation of Pressure Regulating Valves

Cooling Tower;Boiler Systems

Geothermal (Earth-Coupled) Systems

System Checkout

Unit Start-Up

Procedure for starting up the unit, verifying operation in cooling and heating modes, and checking for issues.

Maintenance

Guidance on regular filter changes, annual checkups, and blower motor lubrication.

Unit Check-Out Sheet

Auxiliary Heat

Troubleshooting

UPM Board LED Indications

Explains the meaning of UPM Board LED colors and blink counts for identifying specific fault conditions.

Unit Troubleshooting

Provides a table of common problems, possible causes, and checks/corrections for unit operation issues.

Compressor Ohms

Comfort Alert Module -Flash Codes

HRP Troubleshooting

Electronic Thermostat Installation

Operating Temperatures and Pressures

Wiring Diagrams

Notes

Bosch CE Series Specifications

General

SEER	Up to 20
HSPF	Up to 10
Refrigerant	R-410A
Heating Capacity	18, 000 - 60, 000 BTU/h
Cooling Capacity	18, 000 - 60, 000 BTU/h
Energy Efficiency Ratio (Heating)	Up to 10 HSPF
Energy Efficiency Ratio (Cooling)	Up to 20 SEER
Sound Level	As low as 56 dBA
Stages	Variable Speed
Noise Level (Outdoor Unit)	As low as 56 dBA
Operating Temperature Range (Heating)	Model dependent
Operating Temperature Range (Cooling)	Model dependent
Dimensions (Indoor Unit)	Model dependent
Dimensions (Outdoor Unit)	Model dependent
Weight (Indoor Unit)	Model dependent
Weight (Outdoor Unit)	Model dependent
Series	CE Series