HDG Compact 25 User manual

hdg-bavaria.com
HDG Compact 25/35
HDG Compact 45/50/65
HDG Compact 80
Operating manual

Operation Manual HDG Compact 25 - 80 - Content
3
Content
1 Notes on this manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
1.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
1.2 Structure of the Operating manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
1.3 Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
2 Safety instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.1 Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Basic system design principles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Basic principles for the content of the operating manual . . . . . . . . . . . . . . . . . . .10
Proper and improper manner of operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.2 Residual risks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
2.3 Warnings and safety symbols used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
2.4 Duty of information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
3 Mode of operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
3.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
HDG Compact 25/35 front side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
HDG Compact 25/35 back side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
HDG Compact 45/50/65/80 front side. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
HDG Compact 45/50/65/80 back side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
3.2 Functional description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Overview of heating system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Combustion process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Boiler and weather-compensated heating control HDG Control . . . . . . . . . . . .22
3.3 Technical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
HDG Compact 25/35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
HDG Compact 45/50/65/80 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
3.4 Fuel quality requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Wood chips. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Wood pellets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Pressed wood briquettes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Recommended fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Permitted fuel in accordance with 1st Federal Emission Control Ordinance
(Germany) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Nominal thermal value depending on water content. . . . . . . . . . . . . . . . . . . . . . .29
4 Planning and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
4.1 Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Flue gas pipe side HDG Compact 25 - 80 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
HDG Compact 25 - 80 back side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
4.2 Structural requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Required room sizes and minimum clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Boiler installation site/boiler room. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Operation Manual HDG Compact 25 - 80 - Content
4
Fuel storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.3 Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Chimney. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Electrical system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.4 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.5 Installing the heating system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Installing the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Installing the combustion fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Installing the manual ash removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Installing the automatic ash removal system
HDG Compact 25/35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Installing the automatic ash removal system
HDG Compact 45/50/65. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Installing the heat exchanger cleaner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Installing the feeding system and pressure equalisation hose. . . . . . . . . . . . . . 53
Installing the cladding HDG Compact 25/35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Installing the cladding HDG Compact 45/50/65/80 . . . . . . . . . . . . . . . . . . . . . . . 62
Installing the flue gas temperature sensor and lambda sensor . . . . . . . . . . . . 70
Attaching the pressure equalisation hose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Wiring the modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Installing and adjusting the ash containers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Connecting the chimney . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
4.6 Delivery system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.7 Electrical system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.8 Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.9 Thermal safety device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5 Commissioning the system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
5.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
5.2 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
6 Using the heating system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
6.1 Control unit HDG Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
6.2 Filling the fuel storage room . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Procedure for filling with wood chips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Procedure for filling with pellets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
6.3 Performing a chimney sweep measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
6.4 Switching off the heating system for repair work . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
7 Cleaning and servicing the heating system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
7.1 Cleaning and servicing schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
7.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Generally applicable safety instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Cleaning tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Cleaning the tilting grate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Operation Manual HDG Compact 25 - 80 - Content
5
Checking and emptying the ash container . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Lubricating the feeding system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Lubricate heat exchanger cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Checking the drive chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
Cleaning the cleaning shaft and turbulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Checking and cleaning the lambda sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
Cleaning the flue gas pipe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
Cleaning the ash removal system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
Cleaning the flue gas temperature sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96
Cleaning the ignition fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96
Cleaning the flue gas fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98
Cleaning the pressure equalisation hose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99
Cleaning and lubricating the overfill lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99
Checking the fuel storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
8 Notes on dismantling and disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
8.1 Dismantling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
8.2 Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
9 Declaration of Conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
10 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Operation Manual HDG Compact 25 - 80 - Content
6

1 Notes on this manual – Introduction
7
1 Notes on this manual
1.1 Introduction
EASY AND SAFE OPERATION This Operating manual contains important instructions on the
•HDG Compact 25/35
•HDG Compact 45/50/65
•HDG Compact 80
and how to operate it properly and safely. Following these instruc-
tions helps to avoid dangers, prevent repair costs and downtimes,
maintain reliability and extend the life expectancy of the heating
system.
READING THE OPERATING
MANUAL
This Operating manual must be read and applied by everyone who
operates or works on the heating system HDG Compact 25 - 80.
TECHNICAL CHANGES We continuously develop and improve our boilers. The information
in this edition was correct at the time of going to press.
All details in these instructions on standards, regulations and work-
sheets should be checked before use and should be compared with
the regulations applying locally at the site where the system is in-
stalled.
We reserve the right to make changes which may then differ from the
technical details and illustrations in this Operating manual.
COPYRIGHT Written permission is required from HDG Bavaria GmbH for re-
printing, storage in a data-processing system or transmission by elec-
tronic, mechanical, photographic or any other means, and for copies
or translations of this publication, in whole or in part.
GUARANTEE The terms and conditions of the guarantee of your (central-heating)
boiler can be found in the enclosed information sheet.
SYMBOLS USED In this Operating manual, the following designations and symbols
are used for particularly important information:
1. Instructions to the operator
✓Result of the action described
✎Cross reference for more explanation
•List
–List

1 Notes on this manual – Structure of the Operating manual
8
HDG Compact 25 - 80 - Version 2 - en ©HDG Bavaria GmbH October 2007
1.2 Structure of the Operating manual
The Operating manual is structured as follows:
1.3 Glossary
Chapter This explains ...
1 Notes on this manual ... how to use this Operating manual.
2 Safety notes ... everything on the subject of safety that you should consider
when using the heating system.
3 Mode of operation ... the structure and all of the features of the heating system.
4 Planning and installation . . . how to properly plan and install the heating system.
5 Commissioning the system ... how the heating system is put into initial service.
6 Using the heating system ... how to properly operate the heating system.
7 Cleaning and servicing the
heating system
... how to clean the heating system and who is responsible for its
maintenance.
8 Notes on dismantling and
disposal
... what has to be considered when dismantling and disposing of
the heating system.
Table 1/1 - Structure of the Operating manual
Term Explanation
Actuator This is a component which carries out a certain function in the
heating system, e.g. the stoker auger.
Ash removal augers These transport the combustion chamber ash and fly ash into the
exterior ash containers.
Ash removal motor Drives the ash removal augers.
Delivery system Fuel transport system conveys the fuel from the fuel storage room
to the dosing unit and to the intermediate container.
Display Display on the HDG Control control unit
Feeding system Feeds the fuel to the boiler by means of the rotary feeder and the
stoker auger.
Grate tilting motor Electric motor which moves the tilting grate.
HDG Compact 25 - 80 Boiler for burning wood chips, shavings and wood pellets.
HDG Control Boiler and weather-compensated heating control.
Table 1/2 - Glossary

1 Notes on this manual – Glossary
9
Heating system Comprised of boiler and corresponding accessories.
Main switch Switches off the mains supply to the entire heating system.
Rotary feeder Part of the feeding system - separates the combustion chamber
from the silo and transport unit and acts as back-burn protection.
Sensor Records certain parameters (temperature, fill level) and forwards
them to the control for analysis.
Stoker auger Carries the fuel from the rotary feeder into the combustion cham-
ber.
Wood chips, B1 Machine-chopped wood with a water content of between 15 to 35
percent (in accordance with EN 303-5).
Term Explanation
Table 1/2 - Glossary

2 Safety instructions – Intended use
10
HDG Compact 25 - 80 - Version 2 - en ©HDG Bavaria GmbH 10/2007
2 Safety instructions
2.1 Intended use
BASIC SYSTEM DESIGN PRINCIPLES
BASIC PRINCIPLES The heating system was built using state-of-the-art technology and
conforms to recognised safety regulations. Nevertheless, there is still
a risk of injury or death to users or bystanders, and of adverse effects
upon the heating system or upon other material goods.
Have your specialist heating company provide you with detailed in-
structions on the operation of the heating system.
USING THE HEATING SYSTEM Only use the heating system when it is in perfect condition. Use it
properly, as intended, be aware of safety and hazards, and observe
the Operating manual. Have any faults which could impair safety
fixed immediately.
This device can be used by children over 8 years old and people with
reduced physical, sensory or mental capabilities or a lack of experi-
ence and knowledge, provided they are supervised or have been in-
structed on the safe use of the device and understand the resulting
risks. Children may not play with the device. Cleaning and user main-
tenance must not be carried out by children without supervision.
BASIC PRINCIPLES FOR THE CONTENT OF THE OPERATING MANUAL
SCOPE The content of this operating manual is intended exclusively for the
planning, installation and operation of the HDG Compact 25 - 80
heating systems. Any further implementation of applicable stand-
ards, for example with regard to the installation of the heating
system (pipework, etc.) is not part of this operating manual. HDG Ba-
varia does not assume any liability for this.
PROPER AND IMPROPER MANNER OF OPERATION
PURPOSE OF THE HEATING
SYSTEM
The HDG Compact 25 - 80 heating system is designed for the
standard use of burning wood fuel products made from untreated
wood in the form of wood chips, shavings and pellets for the purpose
of warm water heating.
Any other application is considered improper use. The manufacturer
will accept no liability for any damage resulting from improper use.
The operator bears sole responsibility in such cases.
Proper use includes adherence to the installation, operation and
maintenance requirements specified by the manufacturer.

©HDG Bavaria GmbH 10/2007 HDG Compact 25 - 80 - Version 2 - en
2 Safety instructions – Residual risks
11
Modification of the specified operating values will affect the heating
system’s control programme and could lead to malfunctions. Only
trained maintenance and operating personnel may undertake modi-
fications to the operating values.
The use of materials with other technical burning characteristics re-
quires comprehensive modification of the control parameters by
qualified specialists.
2.2 Residual risks
Despite all precautions, the following residual risks remain:
For more information on fuel, see chapter “3 Mode of operation”,
section “3.4 Fuel quality requirements”.
Caution!
Hot surfaces
Contact with the hot surfaces of the boiler can lead to burns.
Wait until the boiler has cooled down before touching non-insu-
lated components.
Danger!
Danger of asphyxiation and explosion from carbon monoxide
When the boiler is in operation, carbon monoxide escaping from
open cleaning or inspection hatches can cause asphyxiation or ex-
plosions.
Do not leave these open any longer than necessary.
Warning!
Danger of fire
Opening doors and lids to hot combustion residues can pose the
danger of fires.
Keep the openings closed during operation, and when performing
cleaning work, allow the combustion residues to cool down before
you place them in a fireproof container.
Warning!
Danger from suspended loads
The boiler weighs over 700 kg. If the boiler is dropped during trans-
port, persons can be seriously injured and the boiler can be dam-
aged.
Make sure that you use appropriate lifting gear when placing the
boiler.

2 Safety instructions – Warnings and safety symbols used
12
HDG Compact 25 - 80 - Version 2 - en ©HDG Bavaria GmbH 10/2007
2.3 Warnings and safety symbols used
The following warnings and safety symbols are used in this Oper-
ating manual :
Warning!
Danger of injury
The cleaning shaft lid is very heavy and can fall shut. Hands and
arms could thereby be crushed.
Take care not to bump into the opened cleaning shaft lid and cause
it to fall shut.
Warning!
Risk of injury from automatically driven components
When working on the automatic ash removal or on the automatic
heat exchanger cleaner, hands and arms could be injured.
Turn off the main switch when performing any work on these com-
ponents.
Danger!
Dangerous electrical current or voltage
The circuit boards and electrical components carry current.
Have work on electrical components performed only by a qualified
electrician and turn the main switch off.
Warning!
The boiler is under pressure.
Danger!
Dangerous electrical current or voltage
Work in areas marked with this symbol may only be performed by a
qualified electrician.
Warning!
Hazardous area
Working in areas marked with this symbol can lead to serious inju-
ries or to extensive material damage.

©HDG Bavaria GmbH 10/2007 HDG Compact 25 - 80 - Version 2 - en
2 Safety instructions – Warnings and safety symbols used
13
Warning!
Hand injuries can occur
Working in areas marked with this symbol can lead to hand injuries.
Warning!
Automatic start-up
Working in areas marked with this symbol can lead to injuries due
to automatic start-up.
Caution!
Hot surfaces
Working in areas marked with this symbol can lead to burns.
Warning!
Danger of fire
Working in areas marked with this symbol can lead to a fire.
Danger!
Danger of asphyxiation due to lack of oxygen
When working in areas marked with this symbol, there is a danger
of asphyxiation due to high concentrations of carbon monoxide.
Danger!
Danger of explosion
When working in areas marked with this symbol, there is a danger
of explosion due to high concentrations of carbon monoxide.
Warning!
Suspended loads
When working in areas marked with this symbol, there is a danger
of falling objects.
Important!
Frost danger
Only install the heating system in a frost-proof room.
Instructions regarding disposal

2 Safety instructions – Duty of information
14
HDG Compact 25 - 80 - Version 2 - en ©HDG Bavaria GmbH 10/2007
2.4 Duty of information
READING THE OPERATING
MANUAL
Every person performing any tasks on the system is required to read
the Operating manual prior to beginning work, particularly the
chapter “2 Safety instructions”.
This is especially important for persons who only occasionally work
on the heating system, for example when cleaning or servicing it.
The Operating manual must always be kept readily accessible at the
place where heating system is installed.
Additional information for the operator

3 Mode of operation – Overview
15
3 Mode of operation
3.1 Overview
The version of the HDG Compact 25 - 80 heating system installed de-
pends on whether the feeding system is to be fitted
•on the right-hand side or
•on the left-hand
side.
The heating system is equipped as standard with an automatic heat
exchanger cleaning system.
The HDG Compact 80 is already equipped as standard with a de-
ashing system for automatic ash removal to external containers. This
component is also optionally available for the HDG Compact 25 - 65.
When selecting the feeding unit for the HDG Compact 25 - 80
heating system, you can choose between the following:
•TBZ 150 for feeding wood chips, shavings and pellets.
•Pellet suction system with TBZ 90 for feeding pellets.
The HDG Compact 25 - 80 heating system can also be equipped with
the following delivery systems:
•FRA flexi blade delivery system
•Hinged arm delivery system
•Walking floor delivery system
•Inclined auger delivery system
•Pellet delivery system
✎This Operating manual - unless otherwise specified - depicts and
describes the fully equipped version with the TBZ150 feeding
system on the left-hand side.

3 Mode of operation – Overview
16
HDG COMPACT 25/35 FRONT SIDE
1 Combustion chamber temperature sensor
2. Control unit for HDG Control Touch
3 Heat exchanger cleaner drive
4Fluegasfan
5 Flue gas pipe connection
6 Flue gas temperature sensor
7 Heat exchanger surfaces with cleaning turbulators in between
8 Ash removal augers
9Tiltinggrate
10 Combustion chamber primary burning
11 Level indicator
12 Ignition pipe
13 Feeding system
14 Combustion chamber secondary burning
Figure 3/1 - Front side of the HDG Compact 25/35 boiler
12 6
432
14
13 5
1
10 7
11 98

3 Mode of operation – Overview
17
HDG COMPACT 25/35 BACK SIDE
1 Connection of immersion sleeve for thermal safety device (DN 15,
inside thread)
2 Safety heat exchanger connections (DN 15, outside thread)
3Drivemodule
4ExpansionmoduleEM4(optional)
5 Actuator primary air
6 Actuator secondary air
7 Ash removal motor
8 Grate tilting motor
9 Boiler return connection (DN 32 IG)
10 Filling/draining connection (DN 15 IG)
11 Ignition fan
12 Central module
13 Lambda sensor
14 STL release button
15 Boiler supply connection (DN 32 IG)
16 Main switch
Figure 3/2 - HDG Compact 25/35 boiler back side
875
4
3
21
9
11
12
13
16
15
6
10
14

3 Mode of operation – Overview
18
HDG COMPACT 45/50/65/80 FRONT SIDE
1 Combustion chamber temperature sensor
2 Control unit for HDG Control Touch
3 Heat exchanger cleaner drive
4 Flue gas temperature sensor
5Lambdasensor
6 Flue gas pipe connection
7 Heat exchanger surfaces with cleaning turbulators in between
8 Ash walking floor delivery system
9 Ash removal augers
10 Combustion chamber primary burning
11 Tilting grate
12 Level indicator
13 Pressure equalisation hose
14 Feeding system
15 Ignition pipe
16 Combustion chamber secondary burning
Figure 3/3 - Front side of the HDG Compact 45/50/65/80 boiler
2
7 6
53
12
15
14
1 4
1011 8
16
9
13

3 Mode of operation – Overview
19
HDG COMPACT 45/50/65/80 BACK SIDE
1 Boiler return connection (DN 32 IG and DN 40 IG)
2 Immersion sensor connection for thermal safety device
3 Safety heat exchanger connections
4Centralmodule
5Drivemodule
6ExpansionmoduleEM4(optional)
7Combustionairfan
8 Actuator primary air
9 Ash removal motor
10 Grate tilting motor
11 Ignition fan
12 Actuator, secondary air
13 Boiler return connection (DN 32 IG and DN 40 IG)
14 STL release button
15 Main switch
16 Filling/draining connection (DN 15 IG)
Figure 3/4 - HDG Compact 45/50/65/80 boiler back side
1
8 7
42 5
16
3 6
15 13 101112
14 9

3 Mode of operation – Functional description
20
3.2 Functional description
OVERVIEW OF HEATING SYSTEM
The HDG Compact 25 - 80 heating system may contain the following
components:
1 Delivery system
2Feedingsystem
3 HDG Compact 25 - 80 boiler with HDG Control
Figure 3/5 - Overview
1 2 3