Rotex RKHBH008BA User Manual (English)

Questions and Answers:

T
Tracy MonroeJul 31, 2025
How to troubleshoot Rotex Air Conditioner not heating or cooling properly?
- G
  Gabriel WilsonJul 31, 2025
  If the unit is running but not heating or cooling properly, first check the temperature setting on the controller. If that's not the issue, the water flow might be too low. Ensure all shut-off valves are fully open, the water filter is clean, there's no air in the system, the water pressure is above 1 bar when the water is cold, the pump speed is set to the highest level, and the expansion vessel isn't broken. Also, verify that the resistance in the water circuit isn't too high for the pump.
J
Julie EvansAug 4, 2025
Why is my Rotex RKHBH008BA space heating capacity low in cold weather?
- T
  tturnerAug 4, 2025
  If you're experiencing a space heating capacity shortage at low outdoor temperatures, ensure the backup heater operation is activated by checking the field setting [4-00]. Also, verify the thermal protector and thermal fuse of the backup heater haven't been activated or blown, respectively. Make sure booster heater and backup heater are configured to operate simultaneously (field setting [4-01]). Check that the 'equilibrium temperature' field setting [5-01] is properly configured. Finally, if you have a domestic hot water tank, check that the space heating priority temperature settings are configured appropriately. Enable the 'space heating priority status' field setting [5-02] and raise the 'space heating priority temperature' field setting [5-03].
T
Tammy WatkinsAug 8, 2025
What to do if Rotex RKHBH008BA pump is making noise?
- M
  Mark GarciaAug 8, 2025
  If the pump is making noise (cavitation), it could be due to air in the system. Try purging the air. Another cause could be low water pressure at the pump inlet. Check the manometer to ensure the water pressure is above 1 bar when the water is cold, and verify that the manometer and expansion vessel aren't broken. Also, check that the setting of the pre- pressure of the expansion vessel is correct.
T
Taylor RussellAug 13, 2025
Why Rotex RKHBH008BA compressor is not starting?
- S
  Shelly HubbardAug 13, 2025
  If the unit is on but the compressor isn't starting for space or domestic water heating, it might be because the water temperature is too low. The system uses a backup heater to reach a minimum of 15°C. Check the backup heater's power supply, thermal fuse, thermal protector, and contactors. Also, if [D-01]=1 or 2, the wiring requires specific installation. The benefit kWh rate signal might have been sent by the electricity company, wait for the power to return.
R
Rachel KirbyAug 17, 2025
What to do if Rotex RKHBH008BA Air Conditioner water pressure relief valve leaks?
- D
  Deborah CisnerosAug 17, 2025
  If the water pressure relief valve leaks, it may be blocked by dirt. To check, turn the red knob on the valve counter-clockwise. If you don't hear a clacking sound, contact your local dealer. If water continues to run out, close both the water inlet and outlet shut-off valves and then contact your local dealer.
M
Michael HamiltonAug 21, 2025
Why does my Rotex RKHBH008BA Air Conditioner display 'nnnn' when I press a button?
- T
  Tim MurphyAug 21, 2025
  If the user interface displays "nnnn" when pressing certain buttons, it means the current permission level prevents using that button. You need to change the "user permission level" field setting [0-00].
K
Kimberly PhillipsAug 26, 2025
How to fix a broken expansion vessel in Rotex Air Conditioner?
- B
  bellsamuelAug 26, 2025
  To fix the broken expansion vessel, replace it.

Rotex RKHBH008BA Specifications

General

Brand	Rotex
Model	RKHBH008BA
Category	Air Conditioner
Language	English

Summary

Introduction

General information

Provides basic details about the indoor unit and its function within the heat pump system.

Scope of this manual

Outlines the content and coverage of this installation manual.

Model identification

Explains how to identify the specific model of the indoor unit.

Accessories

Accessories supplied with the indoor unit

Lists all accessories included with the indoor unit package.

Safety considerations

Typical application examples

OVERVIEW OF THE INDOOR UNIT

Opening the indoor unit

Instructions on how to access internal components of the indoor unit.

Main components

Switch box main components

Functional diagram

Illustrates the electrical and functional connections of the unit.

INSTALLATION OF THE INDOOR UNIT

Selecting an installation location

Guidelines for choosing a suitable indoor location for the unit.

Dimensions and service space

Specifies required dimensions and clearance for installation and service.

Inspecting, handling and unpacking the unit

Procedures for checking and handling the unit upon delivery.

Mounting the indoor unit

Installation of the EKHBDP drain pan kit (only for RKHBX models)

Instructions for installing the optional drain pan kit.

Refrigerant pipework

Guidelines for connecting the refrigerant pipes to the unit.

Water pipework

Checking the water circuit

Important checks before connecting the water circuit.

Checking the water volume and expansion vessel pre-pressure

Procedures to verify water volume and expansion vessel settings.

Calculating the pre-pressure of the expansion vessel

Checking the maximum allowed water volume

Setting the pre-pressure of the expansion vessel

Connecting the water circuit

Charging water

Piping insulation

Field wiring

Overview

General overview of the field wiring requirements.

Internal wiring - Parts table

Field wiring guidelines

Connection of the indoor unit power supply and communication cable

Connection of the backup heater power supply

Connection of the thermostat cable

Connection of the first set point and second set point contacts

Connection of the valve control cables

Wiring the 3-way valve

Wiring the bottom plate heater

Connection to a benefit kWh rate power supply

Mounting

Relocation of the digital controller

Wiring specifications

START-UP AND CONFIGURATION

DIP switch settings overview

Explains DIP switch settings for unit configuration.

Room thermostat installation configuration

How to configure the unit for room thermostat operation.

Pump operation configuration

Domestic hot water tank installation configuration

Initial start-up at low outdoor ambient temperatures

Pre-operation checks

Field settings

Procedure

Steps to access and modify field settings.

Detailed description

[0] User permission level

Defines user access levels for the interface.

[2] Disinfection function

Configuration for the domestic hot water tank disinfection cycle.

[1] Weather dependent set point (heating operation only)

Settings for adjusting heating based on outdoor temperature.

[3] Auto restart

How the unit resumes operation after a power failure.

[4] Backup/booster heater operation and space heating off temperature

Booster heater operation

Specific settings for booster heater activation.

[5] Equilibrium temperature and space heating priority temperature

Settings for backup heater equilibrium and heating priority.

[6] DT for heat pump domestic water heating mode

[7] DT for booster heater and dual set point control

DT for booster heater

Controls the temperature difference for booster heater operation.

Dual set point control

Enables and configures dual set point functionality.

[8] Domestic water heating mode timer

[8-04] Additional running time at [4-02]/[F-01]

[9] Heating and cooling set point ranges

[C] Setup on EKRP1HB digital I/O PCB

[D] Benefit kWh rate power supply/Local shift value weather dependent

Benefit kWh rate power supply

Settings related to electricity company signals for heater control.

Local shift value weather dependent

Adjusts weather-dependent set points based on local conditions.

[E] Unit information readout

[F] Option setup

Pump operation

Configuration for pump operating modes.

Space cooling permission

Defines conditions for enabling space cooling.

Bottom plate heater control

Settings for the bottom plate heater on the outdoor unit.

Functionality of X14A

Field settings table

TEST RUN AND FINAL CHECK

Final check

Final checks to ensure correct installation.

Test run operation (manual)

Procedure for manually testing unit operations.

MAINTENANCE AND SERVICE

Maintenance activities

Regular checks and inspections for unit upkeep.

TROUBLESHOOTING

General guidelines

Initial steps and precautions before troubleshooting.

Error codes

TECHNICAL SPECIFICATIONS

General

General technical data for the indoor unit.

Electrical specifications

Details regarding the unit's electrical requirements.

Related product manuals

Rotex RKHBH008BA User Manual

Table of Contents

Questions and Answers:

Rotex RKHBH008BA Specifications

Summary

Introduction

General information

Scope of this manual

Model identification

Accessories

Accessories supplied with the indoor unit

Safety considerations

Typical application examples

OVERVIEW OF THE INDOOR UNIT

Opening the indoor unit

Main components

Switch box main components

Functional diagram

INSTALLATION OF THE INDOOR UNIT

Selecting an installation location

Dimensions and service space

Inspecting, handling and unpacking the unit

Mounting the indoor unit

Installation of the EKHBDP drain pan kit (only for RKHBX models)

Refrigerant pipework

Water pipework

Checking the water circuit

Checking the water volume and expansion vessel pre-pressure

Calculating the pre-pressure of the expansion vessel

Checking the maximum allowed water volume

Setting the pre-pressure of the expansion vessel

Connecting the water circuit

Charging water

Piping insulation

Field wiring

Overview

Internal wiring - Parts table

Field wiring guidelines

Connection of the indoor unit power supply and communication cable

Connection of the backup heater power supply

Connection of the thermostat cable

Connection of the first set point and second set point contacts

Connection of the valve control cables

Wiring the 3-way valve

Wiring the bottom plate heater

Connection to a benefit kWh rate power supply

Mounting

Relocation of the digital controller

Wiring specifications

START-UP AND CONFIGURATION

DIP switch settings overview

Room thermostat installation configuration

Pump operation configuration

Domestic hot water tank installation configuration

Initial start-up at low outdoor ambient temperatures

Pre-operation checks

Field settings

Procedure

Detailed description

[0] User permission level

[2] Disinfection function

[1] Weather dependent set point (heating operation only)

[3] Auto restart

[4] Backup/booster heater operation and space heating off temperature

Booster heater operation

[5] Equilibrium temperature and space heating priority temperature

[6] DT for heat pump domestic water heating mode

[7] DT for booster heater and dual set point control

DT for booster heater

Dual set point control

[8] Domestic water heating mode timer

[8-04] Additional running time at [4-02]/[F-01]

[9] Heating and cooling set point ranges

[C] Setup on EKRP1HB digital I/O PCB

[D] Benefit kWh rate power supply/Local shift value weather dependent

Benefit kWh rate power supply

Local shift value weather dependent

[E] Unit information readout

[F] Option setup

Pump operation