Mikrofill ETHOS 70 User manual

CON D ENSINGBOILERS
INSP I R E D EFFI C IENC Y
ETHOS 70, 90, 110 & 130 WALL MOUNTED CONDENSING BOILERS
TECHNICAL DOCUMENTATION
ISSUE 03/16 Rev. 03

TABLE OF CONTENTS
TECHNICAL DOCUMENTATION 03
Technical Data
Dimensions
Safety Guidelines
Conditions
General Guidelines
Service
General Restrictions
Description
General
Working Principle and Design
Application Features
Main Components
Bottom Connections
Boiler Control
Safety Aspects
Delivery & Transport
Delivery
Transport
Moving
Access Requirements
Installation
Regulations
Installation Area
Mounting - Solid Walls
Mounting - Non-Load Bearing Walls
Installation Guidelines
Ventilation
Gas Connection
Water Connections
Electrical Connections
Internal Controls Breakdown (Main PCB)
Internal Controls Breakdown (Control Fascia)
External Controls Breakdown (Din Rail)
Flue Connection
Flue Gas Outlet and Air Inlet Pipe
Flue Adaptor Installation
Flue Gas Data
Flue Length
Calculation of Diameter and Length
Resistance Table
Condense Connections
Safety Valve Connection
Hydraulic System
Pump Characteristics
Shut-Off Valves
Valves (Boilers in Cascade Arrangement)
Water Flow Protection Device
Water Pressure
System Expansion Vessel
Water Pressure Protection Device
Water Temperature
Water Quality
Water Hardness
1.
2.
3.
4.
5.
6.
04
05
06
07
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
Operating Instructions
Operation
Controls
Boiler Module
PCB Symbol Key
Switching On the Appliance
Switching Off the Appliance
Information Display
DHW Operation
Heating Operation
Displaying Information
Table Parameter List
History Mode
Possible Error Codes
Possible Error Codes continued.
Commissioning
General
Reference Value for Maximum Load
Reference Value for Minimum Load
Maximum Load Adjustment
Minimum Load Adjustment
Setting the CO2Value for the ETHOS Range
Conversion from Natural Gas to Propane
Cascade Set-Up
Auto Detection Mode
Cascade Test Mode
Maintenance
Safety
Servicing Schedule
Gas Valve and Venturi
Fan and Burner Assembly (ETHOS 70)
Fan and Burner Assembly (ETHOS 90, 110 and 130)
Pump / Pump Head
Setting / Checking of Electrode and Probe Gaps
Component List
Casing and Electrical Components
Core Components (ETHOS 70)
Core Components (ETHOS 90, 110 and 130)
Conversion Formulae & Factors
Notes
7.
8.
9.
10.
11.
12.
13.
22
23
24
25
26
27
28
29
30
31
31
32
33
34
35
36
37
38
39
40
41
42
44

TECHNICAL DATA
04 TECHNICAL DOCUMENTATION
ETHOS 130
12.4
116
1¼”
¾”
100
100
110/150
420
230
50
6
6200
950
13.0 - 130.0
12.8 - 127.7
14.0 - 140.4
13.6
15.8
5.3
52
75
T 120
200
3.0 - 5.5
90
0.5 - 6.0
17 - 20
17 - 20
30 - 50
8.4
8.4
9.5
33.0
98.2
108.0
95.63
ETHOS 110
10.7
102
1¼”
¾”
100
100
110/150
370
230
50
6
6750
900
11.0 - 110.0
10.7 - 106.9
11.9 - 118.8
11.5
13.4
4.5
52
75
T 120
200
3.0 - 5.5
90
0.5 - 6.0
17 - 20
17 - 20
30 - 50
8.4
8.4
9.5
33.0
97.2
108.0
95.46
ETHOS 90
8.8
91
1¼”
¾”
100
100
110/150
370
230
50
6
6200
900
9.0 - 90.0
8.8 - 87.5
9.7 - 97.2
9.4
10.9
3.7
52
75
T 120
140
3.0 - 5.5
90
0.5 - 6.0
17 - 20
17 - 20
30 - 50
8.4
8.4
9.5
33.0
97.2
108.0
95.46
ETHOS 70
7.0
67
¾”
¾”
80
80
80/125
370
230
50
6
6600
1000
7.0 - 70.0
6.8 - 68.4
7.7 - 76.8
7.4
8.6
2.9
52
75
T 120
140
3.0 - 5.5
90
0.5 - 4.0
17 - 20
17 - 20
30 - 50
8.4
8.4
9.5
33.0
97.7
109.7
96.79
905 x 530 x 475 905 x 530 x 675
With this resistance value the heat output will remain within the specifications indicated on the dataplate; if the resistance is higher, the
heat output will be reduced.
GENERAL
Dimensions (Height x Width x Depth)
Model
Water Content of Appliance
Weight (Empty)
Flow / Return Connections
Gas Connection
Flue Connection
Air Supply Connection
Concentric (Optional)
Power Consumption
Electrical Supply
Frequency
Fuse Protection
Maximum Fan Speed
Minimum Fan Speed
HEATING PERFORMANCE
Nominal Heat Input (Nett)
Nominal Heat Output at 80/60°C
Nominal Heat Output at 50/30°C
Maximum Gas Consumption
TECHNICAL DATA
Flue Gas Dew Point
Flue Temperature at 80/60°C (at ambient temperature of 20°C)
Flue Material Temperature Class
Permitted Maximum Resistance of Flue System*
Condensation pH Value
Maximum CH Flow Temperature
CH Water Pressure (Minimum / Maximum)
Minimum / Maximum Gas Pressure
ENVIRONMENTAL DATA
Flue Gas CO2Content
NOXLevels
Maximum Efficiency (Nett Non-Condensing)
Maximum Efficiency (Nett Condensing)
Seasonal Efficiency
*
mm
litre
kg
BSP
BSP
mm
mm
mm
W
V
Hz
A
RPM
RPM
kW
kW
kW
m3/hr
m3/hr
m3/hr
°C
°C
Pa
°C
bar
mbar
mbar
mbar
%
%
%
mg/kW
%
%
%
G20
G25
G31
G20
G25
G31
G20
G25
G31

DIMENSIONS
TECHNICAL DOCUMENTATION 05
▲ FIGURE 01. DIMENSIONS OF THE ETHOS WALL MOUNTED BOILERS.
• All dimensions are in millimetres unless otherwise specified.
• Data may deviate slightly due to fabrication tolerances.
• We reserve the right to make changes without prior notification.
530
905
110 70
180
65 EF
GG H
245 A
C
D
Ø B
55
75
ETHOS 130
140
100
95
675
75
115
1¼”
¾”
ETHOS 110
140
100
95
675
75
115
1¼”
¾”
ETHOS 90
140
100
95
475
65
125
1¼”
¾”
ETHOS 70
120
80
125
475
65
125
¾”
¾”
mm
mm
mm
mm
mm
mm
in
in
A
B
C
D
E
F
G
H

SAFETY GUIDELINES
06 TECHNICAL DOCUMENTATION
CONDITIONS
Mikrofill Systems Ltd. shall not be liable for any damages caused by non-compliance with this manuals
instructions. Only original parts must be used for service purposes.
GENERAL GUIDELINES
The appliance is not intended for use by persons (including children) with reduced mental, physical or sensory
capabilities, or lack of experience or knowledge, unless they have been given supervision or instruction
concerning the use of the appliance by a person responsible for their safety.
It is a statutory requirement that all gas appliances are installed in accordance with the manufacturers
instructions and all regulations in force. All instructions should be fully read before installing or using the
appliance. All installations should be carried out by competent persons as described in the Gas Safety
(Installation and Use) Regulations i.e. Gas Safe registered and holding current certification.
The manufacturers instructions MUST NOT be taken in any way as overriding statutory obligations.
This boiler has been tested and certified to comply with all necessary European directives, latest building
regulations and efficiency requirements, is CE marked and complies with;
• 2009/142/EC Gas Appliance Directive.
• 2014/35/EU Low Voltage Directive.
• 2014/30/EU Electromagnetic Compatibility Directive.
This boiler should be installed in compliance with;
• Building Regulations.
• Building Regulations (Scotland-Consolidated).
• Building Regulations (Northern Ireland).
• The Health and Safety at Work Act.
• Gas Safety (Installation and Use) Regulations.
• Water Fittings Regulations or Water By-laws in Scotland.
• Local Water Company By-laws
The boiler should not be modified in any way. Any modifications will invalidate the gas approval and
invalidate the warranty.
ATTENTION: HIGH VOLTAGE!
Before opening the boiler casing for maintenance or servicing, the 230 VAC main supply
to the boiler must be disconnected!

SAFETY GUIDELINES
TECHNICAL DOCUMENTATION 07
DESCRIPTION
SERVICE
Should you require any assistance during installation or in the unlikely event of a product failure please do not
hesitate to contact our technical department on 03452 60 60 20.
GENERAL RESTRICTIONS
Mikrofill products should always be used, installed and maintained in accordance with the statutory
requirements, specifications and standards applicable to these installations. Mikrofill cannot be held
responsible for any losses or damage whether direct or consequential that have arisen as a result of incorrect
or poor installation.
GENERAL
The Mikrofill ETHOS wall mounted boilers are environmentally friendly gas fired heating boilers with a
modulation range between approximately 10% and 100% of their maximum output. The appliances have low
NOXand CO emission, which satisfies the most stringent environmental requirements.
The boilers may be used on both open (type B23) as well as room sealed (type C13, C33, C43, C53, C63 or
C83) systems.
The boiler is delivered fully wired, fully assembled, tested and preset complete with emissions report.
WORKING PRINCIPLE AND DESIGN
Air is drawn in as required, via a variable speed fan. The gas valve measures the negative pressure (draught)
in the venturi and modulates the gas valve in response. The gas and air is then thoroughly mixed in the correct
ratio in the fan housing and fired directly into the burner.
The boiler management system compares the actual water flow temperature to the required water
temperature. The management system computes the load required and adjusts the fan speed. This is a
continual process during operation.
The heat transfer takes place in a stainless steel double heat exchanger block. The burner fires into the primary
heat exchanger whilst the second heat exchanger (condenser) is connected downstream in such a manner
that the condense water cannot enter the primary heat exchanger, both heat exchangers consist of several
smooth pipes in the form of a coil and are connected using stainless steel water distribution manifolds.
WARNING!
Particular attention must be given to the safety guidelines as non-compliance will render
the warranty void and may constitute an illegal installation.
The ETHOS range has received CE approval for all relevant European countries and has
been registered under the Product Identification Number 86CN59.

DESCRIPTION
08 TECHNICAL DOCUMENTATION
The design of the boiler incorporates the following:
• Full Operation and Fault Diagnostics via LCD.
• Control / High Limit Sensors.
• Integral Boiler Shunt Pump.
• Integral Safety Relief.
• Integral Weather Compensation (Optional External Sensor Required).
• Frost Protection.
• Pressure Read Out.
• Compatible with most External BMS Options.

DESCRIPTION
TECHNICAL DOCUMENTATION 09
MAIN COMPONENTS:
BOTTOM CONNECTIONS:
* Only present on ETHOS 90, 110 and 130 Heat Exchangers.
ETHOS 70: ETHOS 90, 110 AND 130:
BOTTOM CONNECTIONS:
15 1714 16 18
Air Inlet Connection
Air Inlet Tube
Air Vent Valve*
Combustion Fan
Controls Housing
Flue Gas Temperature Sensor
Flue Outlet Connection
Flow Connection
Condense Syphon
Gas Connection
Gas Valve and Venturi
Grundfos UPML 25-105 130 PWM
Heat Exchanger and Burner Package
Ignition Transformer
Pressure Relief Valve
Sealed Air Inlet Trap (located behind Air Inlet Tube)
Condense Outlet
Return Connection
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
0107
13
07 01
02
09
04
04
1010
09
12 05
11 11
12
06
02
03
06
05
08
13
08

DESCRIPTION
10 TECHNICAL DOCUMENTATION
BOILER CONTROL
If there is a heat demand, and if all necessary conditions have been fulfilled and all safety devices are
satisfied, the boiler will start. This heat requirement will arise if:
• the flow temperature of the boiler is less than the required flow temperature.
• the frost protection has been triggered independently of the operating conditions.
The boiler control unit adjusts the boiler output by changing the fan speed such that the desired temperature
is attained and maintained. The actual flow temperature is controlled within 4°C of the target temperature.
SAFETY ASPECTS
The following safety devices are installed on the boiler:
• Temperature Monitoring System.
• High Limit Temperature Monitoring System.
• Limit Temperature Monitoring System.
• Flame Monitoring by means of Ionisation Measurement.
• Fan Speed Monitoring.
• Flow Monitoring using a combination of Flow and Return Water Temperature Sensor Readings.
If one of these safety systems is activated, the boiler will go to an interlocking or lockout condition and will be
switched off. Lockout conditions can only be reset by pressing the reset button, after rectifying the fault.

DELIVERY & TRANSPORT
TECHNICAL DOCUMENTATION 11
DELIVERY
The boiler is delivered fully assembled, tested and packed.
• Check the boiler for damage upon receipt.
• Check whether the items delivered are correct and in accordance with the items ordered.
TRANSPORT
The packing should only be removed after transportation.
MOVING
Each boiler is packed in its own carton. Refer to the technical data for dimensions and weights in order to work
safely within the Health and Safety guidelines when handling these products.
ACCESS REQUIREMENTS
The dimensions are such that all ETHOS wall mounted boilers can be transported through a standard doorway.

INSTALLATION
12 TECHNICAL DOCUMENTATION
REGULATIONS
The appliance should be installed by a competent installer in accordance with the applicable national and
local standards, rules and regulations (please refer to pages 06 and 07 for safety guidelines).
INSTALLATION AREA
•
•
•
MOUNTING - SOLID WALLS (BRICK OR BLOCK)
Fix the mounting bracket with suitable fixings using a spirit level and ensuring that there is sufficient clearance
around the boiler to allow for access and flue installation.
MOUNTING - NON-LOAD BEARING WALLS (STUDDING OR LIGHTWEIGHT PARTITIONS)
We recommend the use of a purpose designed mounting frame which is available from Mikrofill Systems Ltd.
or alternatively we can supply drawings for site construction of the same.
INSTALLATION GUIDELINES
The following guidelines should be complied with;
•
•
•
The recommended minimum clearances are as follows:
• 750mm to the front (to allow free space for movement).
• 400mm above.
• 250mm below.
• 25mm at the sides.
Due to the low noise level, there should be no need for additional sound insulation of the room.
Due to its compact design, very little installation space is required (see clearance dimensions
below).
The location options for the boiler are increased because it is suitable for both open flued and room
sealed operation.
The device should be installed in a frost free room due to the risk of freezing of the condensate drain.
The built-in protection system is activated when the temperature of the central heating water falls
below 5°C.
Ensure that there is sufficient room around the device for maintenance and the replacement of
components if necessary.

INSTALLATION
TECHNICAL DOCUMENTATION 13
VENTILATION
The ventilation of the installation room should conform to current gas regulations.
GAS CONNECTION
The gas connection is located on the bottom of the appliance (see page 09). It should be installed by a
competent installer in accordance with the applicable national standards.
A suitable isolation valve should be installed for each boiler and should be in an accessible position. Care
should be taken when sizing the pipework to ensure the supply is sufficient for the maximum load operation of
the boiler.
The pressure on the inlet side of the appliance should be reduced to 20 mbar for natural gas (G20) and no
more than 50 mbar for propane (G31). Under full load conditions the measured gas pressure at the gas valve
should be no less than 17 mbar for natural gas (G20) and 30 mbar for propane (G31).
WATER CONNECTIONS
The boiler is designed for sealed systems only and should not be used for open vented systems. For information
and sizing of sealed system equipment, please refer to our pressurisation management brochure.
It is recommended that manually operated valves should be installed between the boiler flow and return
connections and the system.
It is also recommended that the flow and return pipes are securely fixed with brackets. This prevents damage
and makes maintenance easier.
ELECTRICAL CONNECTIONS
The electrical connections should be installed by a competent installer in accordance with applicable
national standards.
The appliance is fully wired in accordance with the electrical diagrams delivered with the appliance.
Electrical terminal connections are located at the base of the boiler and are protected by a metal enclosure.
Access to the terminals is gained by removing the boiler front panel and unscrewing the lid from the
enclosure. Suitable cable entry points are supplied in the form of cable glands.
The appliance is suitable for a 230 V 50 Hz power supply with live / neutral / earth and is polarity sensitive. The
installer should use a local two pole isolating switch with a contact opening of at least 3mm in the 230 V supply
to the boiler. A permanent earth must also be installed. In order to prevent problems due to electromagnetic
radiation, screened cables should be used for all control wiring between the boiler and external
management systems. The screening should be earthed on both sides in accordance with current EMC
directives.
As the boiler incorporates electrical equipment there is an obligation to the installer to ensure that the boiler is
correctly earthed.

INSTALLATION
14 TECHNICAL DOCUMENTATION
INTERNAL CONTROLS BREAKDOWN (MAIN PCB)
[1] Used to either power additional pump or motorised valve.
[2] Only used on ETHOS 70 models.
[3] Only used on ETHOS 90, 110 and 130 models.
01 02 03
04 05 06
01 02 03 04 05
06 07 08 09 10
01 02
03 04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
01
02
03
04
05
06
07
08
01
02
03
04
05
06
01
02
03
04
01
02
03
04
0510
09
08
07
06
X18 F00 F01
X16 X17
X13
X12
X15
X14
X11
X02 X01 X00
▲ FIGURE 02. TOP VIEW OF MAIN PCB.
• X14 Pin 01: Flue Sensor[3]
• X14 Pin 05: Flue Sensor[3]
• X15 Pin 01: Main PCB to Control Fascia
• X15 Pin 02: Main PCB to Control Fascia
• X15 Pin 03: Main PCB to Control Fascia
• X15 Pin 04: Main PCB to Control Fascia
• X15 Pin 05: Main PCB to Control Fascia
• X15 Pin 06: Main PCB to Control Fascia
• X02 Pin 01: Transformer
• X02 Pin 02: Transformer
• X02 Pin 05: Gas Valve Rectified
• X02 Pin 06: Gas Valve Rectified
• X11 Pin 01: AC Fan Interface
• X11 Pin 02: AC Fan Interface
• X11 Pin 04: PWM Supply
• X11 Pin 06: AC Fan Interface
• X11 Pin 07: AC Fan Interface
• X11 Pin 10: PWM Supply
• X13 Pin 01: Pressure Sensor
• X13 Pin 02: Pressure Sensor
• X13 Pin 04: DHW Sensor
• X13 Pin 05: Return Sensor
• X13 Pin 06: Supply Sensor
• X13 Pin 07: Flue Gas High Limit Switch[2]
• X13 Pin 08: Pressure Sensor
• X13 Pin 11: DHW Sensor
• X13 Pin 12: Return Sensor
• X13 Pin 13: Supply Sensor
• X13 Pin 14: Flue Gas High Limit Switch[2]
• X00 Pin 01: Power to Main PCB
• X00 Pin 02: Power to Main PCB
• X01 Pin 02: Pump
• X01 Pin 03: 240 V Output[1]
• X01 Pin 04: 240 V Output[1]
• X01 Pin 05: Fan Mains
• X01 Pin 07: Pump
• X01 Pin 08: 240 V Output[1]
• X01 Pin 10: Fan Mains

INSTALLATION
TECHNICAL DOCUMENTATION 15
INTERNAL CONTROLS BREAKDOWN (CONTROL FASCIA)
EXTERNAL CONTROLS BREAKDOWN (DIN RAIL)
[1] Volt Free Connection (UNDER NO CIRCUMSTANCES MUST VOLTAGE BE APPLIED TO THESE CONNECTIONS).
[2] 240 V Output in no DHW Load Condition (0.8 A).
[3] Used to either power additional Pump or Motorised Valve (0.8 A).
[4] 240 V Output (0.8 A).
[5] Factory fitted link, do not remove unless utilising 0 - 10 V control.
X06
X01X04
X03
X05
▲ FIGURE 03. TOP VIEW OF CONTROL FASCIA.
• X05 Pin 01: Alarm Output
• X05 Pin 02: Alarm Output
• X05 Pin 05: Reset
• X05 Pin 06: Reset
• X06 Pin 02: Communication with Slave
• X06 Pin 03: Communication with Slave
• X06 Pin 04: Communication with Slave
• X04 Pin 01: 0 - 10 V DC Input
• X04 Pin 02: OpenTherm
• X04 Pin 03: OpenTherm
• X04 Pin 04: External Sensor
• X04 Pin 05: External Sensor
• X04 Pin 06: 0 - 10 V DC Input
• X04 Pin 07: CH Cascade Sensor
• X04 Pin 08: CH Cascade Sensor
• X04 Pin 09: Room Thermostat
• X04 Pin 10: Room Thermostat
• X01 Pin 01: Control Fascia to Main PCB
• X01 Pin 02: Control Fascia to Main PCB
• X01 Pin 03: Control Fascia to Main PCB
• X01 Pin 07: Control Fascia to Main PCB
• X01 Pin 08: Control Fascia to Main PCB
• X01 Pin 09: Control Fascia to Main PCB
• X03 Pin 02: Communication with Master
• X03 Pin 04: Communication with Master
• X03 Pin 05: Communication with Master
▲ FIGURE 04. FRONT VIEW OF DIN RAIL.
A
B
C
D
E
F
Live, Earth and Neutral: Incoming Supply
Connections 1 and 2: Room Thermostat[1]
Connections 3 and 4: External Sensor
Connections 5 and 6: DHW Thermostat[1]
Connections 7, 8 and 9[2]:DHW Output[3]
Connection 11[4]:Alarm Output
G
H
I
J
K
Connections 12 and 13: 0 - 10 V DC Input[5]
Connections 14 and 15: OpenTherm
Connections 16, 17 and 18: Communication with Slave
Connections 19, 20 and 21: Communication with Master
Connections 22 and 23: CH Cascade Sensor

INSTALLATION
16 TECHNICAL DOCUMENTATION
FLUE CONNECTION
During installation, a choice can be made between a ‘room sealed’ or ‘open flued’ system. The standard two
pipe (eccentric) connections can be easily converted using the Mikrofill adaptor.
The flue gas discharge outlet and air intake system should be installed by a competent installer according to
applicable national and local standards and specifications. When using multiple boilers on a single application,
care should be taken to ensure compliance with the Clean Air Act.
FLUE GAS OUTLET AND AIR INLET PIPE
The air inlet and flue gas outlet pipes may be single wall, smooth or flexible, and be made of:
• Aluminium (air inlet only)
• Plastic
• Stainless Steel
Always consider the large resistance when using flexible material, and also consider condensate formation
due to the suction of cold air.
Diameter of Air Inlet
Diameter of Flue Gas Outlet
The connection for the air supply is on top of the boiler.
The air supply pipe should be air tight. This is to prevent the suction of ‘false air’. Horizontal components in the
air supply should be installed sloping in the direction of the supply opening.
FLUE ADAPTOR INSTALLATION
Please ensure the flue adaptor, when used, is fitted in the correct orientation as shown below:
• Type
• Type
• Type
• Type
• Type
• Type
• Type
Open type appliance without draught stabiliser, air supply from the room, flue gas discharge
outlet above the roof.
Room sealed appliance, connected to concentric air supply / flue discharge through the wall.
Room sealed appliance, connected to concentric air supply / flue discharge through the roof.
Room sealed appliances in cascade, connected to a common concentric air supply / flue
discharge at the appliance.
Room sealed appliance, connected to a seperate air supply and flue discharge pipe, opening
into different pressure areas.
Room sealed appliance, sold without related connecting and / or discharge fittings.
Room sealed appliances in cascade, connected to seperate air supplies but common flue
discharge through the roof.
B23:
C13:
C33:
C43:
C53:
C63:
C83:
▲ FIGURE 05. DIAMETERS OF AIR INLET AND FLUE GAS OUTLET CONNECTIONS.
ETHOS 130
100
100
ETHOS 110
100
100
ETHOS 90
100
100
ETHOS 70
80
80
mm
mm

INSTALLATION
TECHNICAL DOCUMENTATION 17
FLUE GAS DATA
The flue gas outlet is located on top of the appliance and is designed for direct connection to a corrosion
resistant flue pipe.
The flue gas discharge pipe to be used should be air tight and water tight at the joints and connections, or
should be seamless. Horizontal components in the flue pipe should be installed sloping in the direction of the
appliance (minimum of 25mm per metre).
Care should be taken when making joints to ensure that the seals are not damaged and the joints must be
sited to enable access / inspection (GasSafe TB 008 Ed. 2.1).
A direct connection to a brick chimney is not permissible unless a suitable liner is installed.
The following table gives the flue gas data for all types:
Average Flue Gas Temperature at Full Load
Maximum Permissable Flue Resistance
FLUE LENGTH
Since the boiler is equipped with a ‘premix burner’ with a fan, an over pressure is created in the boiler. This over
pressure is sufficient to overcome the resistance of the burner, the heat exchanger and the chimney.
The back pressure on the boiler depends on:
• the resistance of the flue pipe.
• the degree of cooling of the combustion gases.
• the resistance of the discharge outlet.
The degree of cooling of the combustion gases depends on the following:
• the insulation value of the flue.
• the ambient temperature.
• the flue system and outlet.
There is a maximum over pressure of around 1.4 mbar (140 Pa) for the ETHOS 70and 90 and 2.0 mbar (200 Pa)
for the ETHOS 110 and 130 in the boiler for the flue gas discharge system.
The maximum draught permissible is 0.2 mbar (20 Pa), this should be checked with the flue warm and boilers
not firing. If the draught is above this then flue stabilisers are recommended.
CALCULATION OF DIAMETER AND LENGTH
For the calculation and control of the inner diameter of a discharge system with mechanical discharge,
please refer to the applicable national and local standards and regulations.
ETHOS 130
70
204.1
0.058
200
ETHOS 110
70
171.7
0.049
200
ETHOS 90
70
141.3
0.040
140
ETHOS 70
70
109.9
0.031
140
°C
m3/h
kg/s
Pa
▲ FIGURE 06. FLUE GAS DATA / LOAD 100% / FLOW TEMPERATURE 80°C / RETURN TEMPERATURE 60°C
Quantity of Flue Gas at Full Load

INSTALLATION
18 TECHNICAL DOCUMENTATION
RESISTANCE TABLE
By using either concentric or the two pipe system, different flue lengths can be achieved. In case a concentric system is used, its length
should not exceed 12 metres.
CONCENTRIC FLUE SYSTEM
Model
Vertical Terminal
Horizontal Terminal
Straight Pipe / m
45° Bend
90° Bend
Vertical Terminal
Horizontal Terminal
Straight Pipe / m
45° Bend
90° Bend
TWO PIPE SYSTEM
Air Inlet
Flue Gas Outlet
Air Inlet
Flue Gas Outlet
Example of Calculation for the ETHOS 70 boiler:
Concentric 45° Bend x 2
Concentric 90° Bend x 1
Concentric Pipe 80/125mm, Vertical 3m + Horizontal 1m = Total 4m Concentric Straight Pipe
Vertical Terminal 80/125mm
Concentric 45° Bend:
Concentric 90° Bend:
Concentric Pipe 80/125mm:
Vertical Terminal 80/125mm:
Total Resistance:
ETHOS 130
-
-
-
-
-
143.4
138.3
14.5
19.9
42.7
-
-
-
-
-
-
-
-
3.4
3.8
16.6
42.0
25.0
6.1
7.0
30.2
ETHOS 110
-
-
-
-
-
94.1
90.7
9.8
13.2
29.4
-
-
-
-
-
-
-
-
2.4
2.7
11.7
35.0
18.0
4.0
4.5
19.5
ETHOS 90
-
-
-
-
-
72.6
70.0
7.3
10.1
21.3
-
-
-
-
-
-
-
-
1.7
1.9
8.4
29.0
12.0
3.1
3.6
15.4
ETHOS 70
65.0
79.7
9.3
12.1
14.6
-
-
-
-
-
4.9
6.8
8.1
36.0
19.0
8.9
12.4
14.7
-
-
-
-
-
-
-
-
▲ FIGURE 07. FLUE DISCHARGE RESISTANCE.
2 x 12.1
1 x 14.7
3 x 9.3
Total resistance is 138.6 Pa, so the boiler output is not changed by the resistance (lower than 140 Pa) and the total concentric
length is less than the maximum allowed 12 metres.
* Vertical terminal length includes 1 metre length.
Resistance
24.2 Pa
14.7 Pa
27.9 Pa
65.0 Pa*
138.6 Pa
2 pcs
1 pcs
3m
RESISTANCE SYSTEM (Pa)mm
80/125
80/125
80/125
80/125
80/125
110/150
110/150
110/150
110/150
110/150
80
80
80
80
80
80
80
80
100
100
100
100
100
100
100
100
Straight Pipe / m
45° Bend R = 0.5 D
90° Bend R = 1.0 D
Vertical Terminal
Horizontal Terminal
Straight Pipe / m
45° Bend R = 0.5 D
90° Bend R = 1.0 D
Straight Pipe / m
45° Bend R = 0.5 D
90° Bend R = 1.0 D
Vertical Terminal
Horizontal Terminal
Straight Pipe / m
45° Bend R = 0.5 D
90° Bend R = 1.0 D

INSTALLATION
TECHNICAL DOCUMENTATION 19
CONDENSE CONNECTIONS
The boiler includes an anti syphon condense trap enabling the condense pipework to be taken directly to
drain. The condense water is slightly acidic (pH 3.0 - 5.5) and should be run in a standard drain pipe material,
e.g. acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polyvinyl chloride (PVC), cross-linked polyvinyl
chloride (PVC-C) or unplasticised polyvinyl chloride (PVC-U).
The condensate pipe should ideally run and terminate internally to a soil stack or waste pipe. Alternatively, the
condensate can be discharged in to the rainwater system or a purpose-made soakaway. Whichever method
is used must conform to applicable national and local standards and regulations. All connecting drainage
pipework should have a fall of at least 2.5° to the horizontal, or approximately 25mm per metre of pipe run. If
the drainage pipe has external run it should be kept to a minimum length with a minimum diameter of 22mm
and be insulated in order to minimise the effects of freezing. It should be noted that connection of a
condensate pipe to a drain may be subject to building controls.
SAFETY VALVE CONNECTION
The discharge pipe from the safety valve shall be self draining and terminate in a visible position where the
discharge cannot result in hazard to any person or to the plant. The size of the discharge pipe shall be no less
than the nominal size of the valve outlet.
HYDRAULIC SYSTEM
The minimum required water circulation over the boiler should be maintained at all times (equivalent to ΔT
25°K at full load). The minimum required water circulation should not be adversely affected by the use of
valves, non-return valves, systems in which several boilers are connected to a common distribution pipe etc.
The maximum water flow is achieved at ΔT 15°K.
Pump Data
* Maximum power consumed is given in Pump Position 03.
The boiler has a pump control circuit. When the boiler is enabled, the pump is switched on. If the boiler is
disabled, the pump will continue to run for a few minutes. The standard run on time is two minutes, but this can
be adjusted.
ETHOS 130
5.57
31.0
40.0
9.0
140
ETHOS 110
4.71
22.5
52.0
29.5
140
ETHOS 90
3.86
24.5
66.0
41.5
140
ETHOS 70
3.00
45.0
82.0
37.0
140
m3/h
kPa
kPa
kPa
W
Nominal Flow Rate (Q)
Boiler Resistance Nominal Flow (R)
Pump Head at Nominal Flow (Q)
Available Head at Nominal Flow (Q)
Maximum Power Consumption*
▲ FIGURE 08. WATER FLOW QUANTITY AND PUMP DATA FOR THE WALL MOUNTED ETHOS RANGE.
ΔT 20°K

INSTALLATION
20 TECHNICAL DOCUMENTATION
UPML 25-105 130 PWM
ELECTRICAL DATA: 1 x 230 V, 50 Hz
DIMENSIONAL DRAWINGS AND CONTROL BOX POSITIONS (IN MILLIMETRES)
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
Q [m³/h]
0
2
4
6
8
10
[m]
H
0
20
40
60
80
100
[kPa]
p
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
Q [l/s]
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
Q [m³/h]
0
20
40
60
80
100
120
140
[W]
P1
SPEED
Minimum
Maximum
P1[W]
3
140
I1/1 [A]
0.04
1.1
95
130
50
64
131
22
27 112