MHS Boilers STRATA1 Series User guide

WALL MOUNTED, GAS FIRED,
ULTRA HIGH EFFICIENCY CONDENSING BOILER
INSTRUCTIONS FOR INSTALLATION, SERVICING
& OPERATION FOR MODELS 45, 60 & 75
STRATA1
L 102

2
STRATA1
Index
page section
3
. . . . . . . . . . . . . 1.0 General Notes
4-5 . . . . . . . . . . . . 2.0 Product Description
6 . . . . . . . . . . . . . 3.0 Technical Data & Dimensions
7 . . . . . . . . . . . . . 4.0 Delivery Consignment/Unpacking The Boiler
. . . . . . . . . . . . . . 5.0 Boiler Location
. . . . . . . . . . . . . . 6.0 Installation Clearances
8 . . . . . . . . . . . . . 7.0 Wall Mounting
. . . . . . . . . . . . . . 8.0 Gas Connection
9 . . . . . . . . . . . . . 9.0 System Flow & Return Connections
. . . . . . . . . . . . . . 10.0 Condense Waste Connection
10 . . . . . . . . . . . . 10.0 Condense Waste Connection (contd)
. . . . . . . . . . . . . . 11.0 Flue Combustion Air Connection - General
11 . . . . . . . . . . . . 12.0 Conventional Flue Installation
12-18 . . . . . . . . . . 13.0 Room Sealed Flue Installations
19 . . . . . . . . . . . . 14.0 Examples of Calculating Flue Pressure Loss
20 . . . . . . . . . . . . 14.1 Calculating Flue Resistance
20-21 . . . . . . . . . . 15.0 Flue Terminal Positions
22-23 . . . . . . . . . . 16.0 Ventilation Requirements Single Appliances
24-32 . . . . . . . . . . 17.0 Hydraulic system Design (circuit diagrams)
33 . . . . . . . . . . . . 17.1 Filling The System
. . . . . . . . . . . . . . 17.2 Water Treatment System Cleaning
34 . . . . . . . . . . . . 17.3 Inclusion of Strainers
. . . . . . . . . . . . . . 17.4 Low Water Pressure Protection
. . . . . . . . . . . . . . 17.5 Care With The Use of Soldering Flux
. . . . . . . . . . . . . . 18.0 Electrical Connections
35-43 . . . . . . . . . . 18.0 Electrical Connections (contd)
44-45 . . . . . . . . . . 18.1 Optional Matched controls
46 . . . . . . . . . . . . 18.2 0-3/0-10 Volt Control
. . . . . . . . . . . . . . 19.0 Commissioning The Strata 1 Boiler
47 . . . . . . . . . . . . 19.1 Pre-Commissioning Checks
. . . . . . . . . . . . . . 19.2 LPG Conversion Procedure
. . . . . . . . . . . . . . 19.3 First Firing
48 . . . . . . . . . . . . 19.1.1 Dip Switch Settings
49 . . . . . . . . . . . . 19.3 First Firing (contd)
50 . . . . . . . . . . . . 19.3 First Firing (contd)
50-52 . . . . . . . . . . 19.4 Setting Weather Compensation
53 . . . . . . . . . . . . 19.5 Setting Domestic Hot Water Temperature
. . . . . . . . . . . . . . 19.6 Service Button/Setting Heating Output
54 . . . . . . . . . . . . 19.6 Service Button/Setting Heating Output (contd)
. . . . . . . . . . . . . . 19.7 Output For Charging Hot Water
. . . . . . . . . . . . . .
20.0 Setting The Boiler To Work
55 . . . . . . . . . . . . 21.0 Servicing Instruction
. . . . . . . . . . . . . . 21.1 Inspection
55-56 . . . . . . . . . . 21.2 Maintenance
57-59 . . . . . . . . . . 22.1 Screen Display/Diagnosis Of Faults
59-60 . . . . . . . . . . 22.2 (Possible) Causes Of Fault & Corrective Action
61 . . . . . . . . . . . . 23.0 Instructing The User
. . . . . . . . . . . . . . 23.1 To Turn On the Appliance
. . . . . . . . . . . . . . 23.2 To Turn Off the Appliance
62 . . . . . . . . . . . . 24.0 Strata 1 45, 60, 75 Expploded View

3
1.0 general
notes
STRATA1
These instructions are intended to assist the installer, commissioning engineer, maintenance engineer
and user with the installation, maintenance and usage of Strata 1, 45, 60 and 75 models gas fired
condensing boilers.
Please read this manual fully before commencing the installation of the appliance. The Strata 1 must
only be installed by persons deemed to be competent i.e. Corgi Registered. This manual must be handed
to the appliance user following completion of the installation.
conformity statement
Strata 1 45, 60, & 75 boilers are manufactured to the highest standard of quality, performance and
safety, in accordance with EC standards. Strata 1 45, 60 & 75 boilers carry the CE mark.
installation requirements
The installation of Strata 1 45, 60 & 75 boilers must be in accordance with the relevant requirements
of Gas Safety (Installation and Use) Regulations 1994, Health & Safety at Work Act, Building Regulations,
I.E.E. Regulations, Construction (Design & Management) Regulations 1994, Local Authority Bye-Laws,
Local and National Water Bye-Laws, Fire Authority Regulations and Insurance Company requirements.
The following Codes of Practice are also applicable:-
• BS6798: 1987 Specification for installation of gas fired hot water boilers of rated input not
exceeding 60kW.
• BS6880 Code of Practice for low temperature, hot water heating systems of output greater than
45kW. Parts 1, 2 and 3: 1988.
• CP342 Part 2: 1974 Code of Practice for centralised hot water supply.
• BS5440-1:2000 1991 Specification for gas fired hot water boilers of rated inputs between 60kW
and 2MW.
• IGE/UP/2 Gas installation pipework, boosters and compressors on industrial and
commercial premises.
• CIBSE Guide Reference sections B7, B11 and B13.
• BS5440-1:2000 - Installation of flues and ventilation for gas appliances of rated input not exceeding
70kW nett (1st, 2nd and 3rd family gases). Part 1: Specification for the installation of flues.
• BS5440-2: 2000 Installation and maintenance of flues and ventilation for gas appliances of rated input
not exceeding 70kW nett (1st, 2nd and 3rd family gases) Part 2: Specification for installation and
maintenance of ventilation for gas appliances.
• IGE/UP/10 Installation of gas appliances in industrial and commercial premises.

4
STRATA1
2.0 product
description
The Strata 1 range of wall mounted gas fired condensing boilers are state of the art appliances which
include a comprehensive range of features. The appliance must only be used on sealed and pressurised
systems. System design must take into account the boiler operating ∆t of 20°C.
wall mounted with compact dimensions
At 900H x 458W x 435D, the Strata 1 boiler provides maximum heat from minimum dimensions
without compromising serviceability.
fully modulating heat output
The output of the boiler is fully variable, sliding between (approx.) 20% to 100%, which automatically
and instantly adjusts to match the needs of the system. The percentage of power at any given time can be
dictated by either outside air temperature, flow temperature, return temperature, stored domestic hot
water temperature, or room temperature, or a combination of the aforementioned.
fully condensing stainless steel heat exchanger
The Strata 1 boiler is designed with extended heat exchange surface area and is fabricated from
corrosion resistant long-life stainless steel. The unique Spiranox heat exchanger will return operating
efficiencies from 86% gross (96% nett) at 60°C return temperature, up to 97% gross (107% nett), at 30°C
return temperature.
extremely low harmful emissions
The boiler utilises 100% pre-mix gas/air fed at positive pressure to the metal fibre sheathed radiant
burners. The combustion system incorporates internal flue gas re-circulation and this combined with the
precise nature of pre-mix fuel/air control, gives ultra low emissions to satisfy the most stringent emission
regulations in the world currently. That is: < 20mg/kWh NOx (14 ppm DAF) and < 14mg/kWh CO (13
ppm DAF). The fully modulating nature of the appliance also reduces emissions by avoiding repeated
start/stops and the associated increase in emissions, which occurs with burner on/off cycling.
accurate variable burner output control
The pre-mix burner fans have low voltage direct current drive motors with pulse relay counting. This
system allows precise control over fan speed/combustion air volumes. Coupled with a gas valve system set
to provide proportionately measured volumes of fuel to air, which allows extremely accurate and instant
variable burner output control to be achieved.
energy saving
In addition to the extremely efficient burner and heat exchanger system employed in the Strata 1, each
appliance includes modulating speed boiler primary pumps.
This feature allows the boiler to self-maintain a 20°C ∆t across the heat exchanger, optimising the heat
exchanger efficiency and reducing also the electrical consumption of the pump motors. The result is a
seasonal increase in boiler efficiency of a further 7-10% and a reduction in pump electricity consumption of
up to 70%.

5
STRATA1
2.0 product description (contd)
natural gas or LPG
Appliances can be supplied for use with natural gas (G20) or LPG (G31).
comprehensive microprocessor control
The boiler control panel includes a user friendly microprocessor control centre which manages the
entire function of the appliance and encompasses:-
1. Management of the essential safety functions of burner ignition and flame monitoring.
2. Water high temperature and flue gas high temperature safety cut out.
3. Modulation of the boiler output and pump speeds in conjunction with operating temperature control.
4. LCD display screen with two lines of text to continuously display operational or fault status.
5. In built weather compensator to provide direct-on boiler VT flow temperature (if required).
6. Remote stored hot water temperature control.
7. In built 2 stage boiler frost protection program.
8. In built pump exercising program to avoid standstill seizure.
9. Cold start boost facility.
10. PC compatibility with data logging which allows communication with the boiler via a lap-top computer
to review/modify operational parameters and access operational history as an aid to fault finding and
preventative maintenance.
11. Range rate adjustment which allows the power to be set to accurately match the maximum needs of
the system, with the facility to set a different firing rate for heating. Output to hot water self adjusts to
the heat transfer capability of the calorifier.
12. Facility to connect optional matched control components which allow the boiler to control a heating
circuit pump, (PR01) HWS primary pump or diverter valve and an underfloor circuit mixing valve and
pump (MR03), plus the ability for the boiler to be controlled by a remote multi function modulating
room unit (RE2132). Multiple boilers may be connected to a modulating Kaskade manager (KKM2) or
controlled via a 0-3 or 0-10v * signal (*via adaptor) which further enhances the operating efficiency of
a larger load modular boiler system.
room sealed option
If required, the boiler may be installed to be completely room sealed, taking combustion air directly
from outside the building, using a 125/80 concentric air duct/flue duct system. Inherent safety is afforded
by the negative pressure within the boiler casing, which in the event of incorrect sealing results in safe
inward air leakage only.
extended flue lengths
The excess fan pressure from the combustion system is 100 Pa, which allows the appliance to be
exhausted using small diameter PPS plastic flue components, over long distances, allowing for complete
flexibility in boiler siting.
designed for ease of maintenance
Although compact, the Strata 1 does not compromise serviceability. The appliance has been engineered
to be easy to maintain with even the most major of service operations being able to be completed easily
and quickly with the minimum of tools.
guarantee
The heat exchanger carries a five year guarantee against manufacturing or material defect. All other
parts carry a one year warranty against manufacturing or material defect.

6
STRATA1
3.0 technical data
& dimensions
Model Strata 1
Nominal Heat Input Nett (max) kW
Nominal Heat Output 80/60°CkW
Nominal Heat Output 50/30°CkW
Input Rate Nat Gas (max) m3/h
Input Rate LPG G31 (max) m3/h
Minimum/Maximum Gas Pressure mbar
Flue Gas Volume (Hot) m3/h
Pressure at Flue Outlet Pa
Maximum Working Pressure Bar
Minimum Working Pressure Bar
Maximum Flow Temperature °C
Power Supply V
Fuse Rating A
Average Power Consumption Watts
Water Content L
Weight (Dry) kg
Design ∆t°C
45
43
41.3
45.2
4.7
1.76
18/60
64
100
3.0
0.5
85
230
3.0
115
6
60
20
60
57
54.7
59.9
5.9
2.33
18/60
81
100
3.0
0.5
85
230
3.0
115
7
66
20
75
72
69.1
75.6
7.6
2.95
18/60
104
100
3.0
0.5
85
230
3.0
115
8
73
20
38
108
229
458
55
231
435
123
4
50
950
front - all models
plan - models 45/60/75
12567 8
38 108
193
238
35
24
55
underside - models 45/60/75
pH of Condense Water 4 to 5.5
Connection Strata 1
1. Return
2. Flow
3. Flue Gas (OD)
4. Air Duct (OD)
5. Condense Syphon
Cleaning Point (capped)
6. Condense Waste
7. Cable Entries
8. Gas
45
11/4" BSP-M
11/4" BSP-M
80mm
125mm
3/4" BSP
3/4" BSP-M
3/4" BSP-M
60
11/4" BSP-M
11/4" BSP-M
80mm
125mm
3/4" BSP
3/4" BSP-M
3/4" BSP-M
75
11/4" BSP-M
11/4" BSP-M
80mm
125mm
3/4" BSP
3/4" BSP-M
3/4" BSP-M
Multiple Grometts

77
STRATA1
4.0 delivery consignment
/unpacking the boiler
The boiler is delivered as a consignment of a carton containing the boiler and associated fittings, plus
any other optional ancillary flue or control components in separate cartons.
The boiler carton contains:-
●Assembled boiler
●Wall mounting bracket
●Fittings carton including 2Nr 11/4”x 11/4”x 1/2”BSP Tees, 2Nr 11/4”x 1/2”BSP reducing sockets,
1Nr 3/4”BSP Inlet x 1”BSP outlet safety valve set 3.0 bar, 1Nr 3/4”x 1/2”BSP reducing nipple (for
safety valve inlet) and 1Nr outside air temperature sensor.
To unpack the boiler, the palleted carton should be laid on the floor. Carefully cut the nylon bands and
lift away fibre board protective panel. Open carton top and lift out wall hanging bracket and fittings bag.
Remove packing material and lift away bottomless carton. With 2 men, carefully lift boiler from palette by
holding grey rear chassis only.
To remove the casing from the boiler, slacken the screw in the underside of the casing, unlatch left and
right hand catches on underside of case, pull casing slightly to the front and lift upwards to disengage casing
hooks from rear chassis and then remove casing to the front.
5.0 boiler
location
The Strata 1 Boiler is not suitable for installation external to a building. The position chosen for the
boiler must be a structurally sound wall capable of supporting the weight of the boiler and any ancillaries.
The position should allow for access to a condense waste drain nearby or an alternative is to install a
condense sump receptacle and condense disposal pump which should remove the condense waste water
to a remote drain. The wall mounting position of the boiler must allow the boiler to be true plumb vertical
to ensure correct operation of the internal gravity flow condense system. The position for the boiler must
satisfy the requirements of BS6798:1987 or BS6644:1991.
6.0 installation
clearances
For ease of installation, commissioning and maintenance the following minimum clearances should
be observed:-
Sides 50mm
Above 250mm
Below 150mm
Front 450mm

8
STRATA1
7.0 wall
mounting
The Strata 1 boiler mounts to the wall via
a wall mounting bracket which interlocks to a
rail mounted upon the rear of the boiler. The
wall mounting bracket should be firmly fixed
to the wall using suitable fixings with
countersunk heads. The wall mounting
bracket positioning detail is shown in fig 1.
The boiler must be carefully offered up to the
wall so that the rail on the rear of the boiler
is just above the wall mounting bracket and
then the boiler should be lowered to engage
the bracket and rail. Lifting is advised with 2
persons. Do NOTlift the boiler by the
internal parts of the appliance.
important Note
When viewed from the side, the
north/south axis of the boiler must be
vertical. The appliance must not be inclined
out from the top, if necessary block or shim
behind the bottom rear of the boiler to
achieve a vertical installation.
8.0 gas
connection
The gas connection is located at the base
of the appliance rear r/h side, see fig 2.
The pipe size used to supply the
appliance must not be smaller than the gas
connection size on the appliance.
The connection to the appliance
must include a suitable method of
disconnection and a gas control cock must be
installed adjacent to the appliance for
isolation purposes.
The gas pipe used to supply the appliance
must not allow a pressure drop of greater
than 1m bar from the meter to the appliance.
The nominal inlet working gas pressure
measured at the appliance should be
20.0 mbar for Nat Gas (G20) or 37 mbar for
LPG (G31).
A gas pressure test point should be
installed between the gas control cock and
the appliance, so that nominal inlet gas
pressure test can be undertaken.
458
170
3 x ø7.0
170
735 900
165
50
Gas Connection
3/4" BSP Male
Fig 2.
Fig 1.

STRATA1
9
Note The Strata 1 boiler must only be installed on sealed and pressurised systems. The maximum
working pressure of the boiler = 3 bar. A safety valve set 3.0 bar is supplied with the boiler and must be
installed onto the flow pipe adjacent to the boiler. It is recommended that the final working pressure (hot)
of the system does not exceed 2.3 bar.
The boiler is equipped with 2 sets of 1 1/4" BSP Male flow & return connections which are located top
rear L/h side & bottom rear L/h side. See figs 3&4.
The installer may choose to use both top connections or both bottom connections or one of each (e.g.
flow-top, return-bottom). The appliance is supplied complete with 2Nr 1 1/4" x 1/2" BSP reducing sockets
(see fig 3. item A) which may be used either at the top of the appliance (when flow and return connections
are made to the lower boiler connections) to install air vents or be used at the bottom flow and return
connections (when system connecting are to the top of the appliance) to install drain cocks.
The appliance is supplied with 2Nr 1 1/4" x 1 1/4" x 1/2" BSP Tees (see fig 4. item B) which may be used
to connect the supplied safety valve into the flow pipe adjacent to the appliance and either a system filling
point/expansion vessel or a draincock. The flow and return pipework should include isolation values and a
method of disconnection local to the boiler.
9.0 system flow
& return connections
10.0 condense
waste connection
Return
A
B
Fig 3. Fig 4.
Flow
Flow
Return
The condense waste connection is located at the underside rear of the appliance see fig 5. The
condense syphon cleaning point is factory fitted with a heavy grade black plastic cap which MUST NOT BE
REMOVED (see fig 5) apart from routine maintenance cleaning operations and must be in place whenever
the appliance is in operation. WARNING operating the appliance with the cap removed from the syphon
cleaning point will cause products of combustion to be discharged from the cleaning point.
The condense waste connection is a 3/4" BSP Male threaded stub fabricated from
plastic. The installer must connect to this stub, a condense waste pipe fabricated
from plastic tube and fittings (3/4", 22mm, overflow pipe is considered suitable).
Copper Tube is not acceptable. The condense waste pipe must fall continuously
from the appliance to suitable nearby drain.

10
STRATA1
10.0 condense waste connection (contd)
If any part of the condense waste pipe is to be
run external to the building or is at risk of freezing,
then the pipe must be suitably insulated to protect
from freezing.
If a suitable drain for accepting the condense
waste is not available nearby to, and below the
boiler, (e.g. boiler installed in a basement below
ground level location), then a suitable condense
sump receptacle with a discharge pump should be
installed below the boiler to remove the condense
to a remote drain.
When making the condense waste pipe
connection to the boiler, do not use adhesives, it is
recommended to lightly apply a suitable jointing
tape (PTFE or similar) and use only light pressure to connect fittings to the appliance to avoid damage to
the condense waste outlet assembly.
It is recommended that the condense waste pipework should include a method of disconnection and
cleaning points.
11.0 flue/combustion
air connection - general
The flue connection and combustion air inlet
to the appliance are located on the top of
the appliance see fig 6. These connections are
arranged concentrically with the 80mm flue gas
connection centrally within the 125mm air inlet
connection. There are two options for flueing the
Strata 1 boiler.
i) Conventionally, using flue gas tube only and
air for combustion from the room or
compartment in which the appliance is installed. If
using a conventional flue arrangement then the
room or compartment must be ventilated in
accordance with the requirements of BS 6644 or
BS5440 as appropriate. For guidance on ventilation
see section 16.
ii) Room sealed using concentric 80/125
components or two seperate tubes where air for
combustion is taken from outside of the building.
When using a room sealed flue, where air for
combustion is provided from outside of the building
directly to the appliance, ventilation to a
compartment may still be required - See section 16
for general space cooling.
Multiple Boilers
On common flues serving multiple boilers, contact MHS Boilers Ltd.
Important Note
Where the Strata 1 is to be installed in an application where the combustion air
is likely to be contaminated with oxidising agents, such as swimming pool areas,
special industrial processes etc, then the appliance must be room sealed.
typical modular
flue arrangement
Inspection
Area
Air Inlet
Flue gas
Connection
Fig 6.
Condense
Waste
Connection
Syphon Cleaning Point
MUST remain capped
Fig 5.

11
STRATA1
12.0 conventional
flue installation
The Strata 1 boiler has an excess pressure combustion system, which coupled with the very low flue
gas temperatures produced allows the appliance to exhausted over considerable distances using 80mm
Polypropylene PPS flue pipe and fittings. Suitable flue pipe and fittings are available from MHS Boilers Ltd
and are listed below.
The flue should be installed to have at least a 3˚fall to the boiler to allow any condense formed in the
flue to run back to the boiler.
The flue system used must be gas and water tight and must be adequately supported over it’s entire
length. Support at 1 metre intervals. It is not necessary to install a terminal to the flue system, however, a
mesh guard should be included to prevent blockage or entry of foreign material. Straight lengths may be
cut to size with any surplus cut from the plain end. Tube ends should be cut square and de-burred.
Care should be taken when selecting a position for a low level discharge or discharge adjacent
to windows etc as the flue terminal will plume heavily and the white water vapour discharge may cause a
visual nuisance.
Flue components available from MHS Boilers Ltd.
80 mm PPS Flue Tube x 1000 mm long
(effective length 945 mm)
80 mm PPS Flue Bend x 90°
80 mm PPS Flue Bend x 45°
80 mm Wall Fixing Bracket - Aluminium
80 mm Bird Mesh Cap - Plated Steel
The above flue components
are light grey self coloured
Polypropylene moulded com-
ponents with push together
spigot and socket joints with
integral seal ring located in the
socket.
If fire stop seals are required
to be installed where PPS plastic
flue components pass through
walls, floors or ceilings then
suitable fire stop seals are
available from:-
Nullifire Ltd
Torrington Avenue
Coventry CV4 9TJ
Tel [phone]
Fax [phone]
Dufaylite
Developments Ltd
Cromwell Road, St Neots
Huntingdon PE19 1QW
Tel [phone]
Fax [phone]
Quelfire
PO Box 35, Altrincham
Cheshire WA14 5QA
Tel [phone]
1000 mm
Effective Length 945mm
137
125
ø80
ø80
50
65 75
ø80 50
100
150
50
80 øPPS
Flue Tube
x 1000
long
80 ø
PPS Flue
Bend
x 90º
80 ø
PPS Flue
Bend
x 45º
80 øWall
Fixing Bracket
ø5 Woodscrew
fitting
100 mm PPS Flue Tube x 1000 Long (Effective Length 945 mm)
100 mm PPS Flue Bend x 90°
100 mm PPS Flue Bend x 45°
100 mm Wall Fixing Bracket
100 mm Bird Mesh Cap - Plated Steel
80 x 100 mm Increaser
80 ø PPS Flue Components
100 ID
56
50
150
80 x 100 PPS
Increaser
End Slip
80

12
STRATA1
13.0 room sealed
flue installations
The Strata 1 boiler has an excess pressure combustion system, which coupled with the very low flue
gas temperatures produced allows the appliance to be exhausted and supplied with room sealed
combustion air using a concentric flue arrangement of 80 mm PPS polypropylene flue pipe within a 125 mm
outer painted metal air tube over considerable distances. A range of concentric flue components are
available from MHS Boilers Ltd and are listed below. Alternatively, two seperate tubes, one carrying
combustion air and one carrying flue gas may be used in conjunction with the appropriate adaptor.
The concentric flue system should be installed to have at least a 3°fall to the boiler to allow any
condense formed in the flue to run back to the boiler.
The flue system must be gas and water tight and must be adequately supported over it’s entire length.
Support at 1.5m intervals. Horizontal Discharge and Vertical Discharge Terminal Sets are available.
Care should be taken when selecting a position for a low level discharge or discharge adjacent to
windows etc as the flue terminal will plume heavily and the white water vapour discharge may cause a
visual nuisance.
Concentric flue components have push together spigot and socket joints. The inner PPS flue gas tube
has seal rings located in the socket component. The outer air tube has EPDM rubber seal rings located in
the socket component.
To aid assembly and assurance that the joints have been fully pushed home, the seal rings and make
ends of tubes/fittings should be lightly lubricated with silicone grease.
list of concentric flue components
●80/125 Concentric wall terminal set:- comprises 500 mm (845 mm*) straight length with made on
terminal, 90°concentric bend and wall bezel plates.
●80/125 Concentric roof terminal set:- comprises 1000 mm straight length with made on terminal and
1Nr 125 wall bracket.
●125 pitched roof tile flashing for use with concentric roof terminal set, adjustable between 25°to 50°.
●125 flat roof flashing for use with concentric roof terminal set.
●80/125 Concentric flue tube set x 1000 mm.
●80/125 Concentric flue tube set x 500 mm.
●80/125 Concentric 93°Bend.
●80/125 Concentric 45°Bend.
●125 Wall bracket assembly.
●80/125 Concentric Vertically Extendable Discharge Room Sealed Wall Terminal Assembly - For use
where a standard wall terminal may cause visual flue gas pluming nuisance. Includes 90°Concentric
bend, wall bezel plates and silicone mastic. Used in conjunction with additional 80 mm pps flue gas tube
and fittings listed on page 10.
●80/125 Concentric to 2 x 80 mm Separate Tubes Adaptor.
●80/125 to 100/150 Concentric Increaser (Not Shown).
●100/150 Concentric Wall Terminal (Not Shown).
●100/150 Concentric Roof Terminal (Not Shown).
●100/150 Concentric Flue Tube Set x 1000 mm (Not Shown).
●100/150 Concentric Flue Tube Set x 500 mm (Not Shown).
●100/150 Concentric 93°C Bend (Not Shown).
●100/150 Concentric 45°C Bend (Not Shown).

13
STRATA1
13.0 room sealed flue installations (contd)
497
1000
Effective Length 950 mm
994
Effective Length 450mm
125 80
125
110
75
40
75
40
80
178
75
ø7mm "Drive In"
Fixing C/W Wall Plug
90
125
125
110
40
40
80
125
93º
80
80/125
Concentric
Tube x
500mm
80/125
Concentric
Bend x 45º
ø125 Wall
Fixing
Bracket
80/125
Concentric
Tube x
1000mm
80/125
Concentric
bend x 93º
491
80/125 concentric roof terminal & accessories
80/125
Concentric
Roof
Terminal
Assembly
80
125
1170
513 513
130
390
500
500
Circular 125 Spun
Aluminium Flat Roof
Flashing
Pitched Roof
Flashing - Adjustable
25-38º& 37-50º
125 Pitched Roof
Adjustable Flashing.
Adjustable between 25-38º
and 37-50º
Lead Apron 1.3mm
458
229
355178900
155
120
80 80
plan
80/125
Concentric
to 2 x 80 mm
Tubes
Adaptor
Flue
Gas Air for Combustion

14
STRATA1
13.0 room sealed flue installations (contd)
installation of standard wall terminal with
side outlet
In order to determine the length of concentric tube required to correctly terminate a side outlet
arrangement, the following procedure should be followed:
1. Measure wall thickness W in mm - see fig 7.
2. Measure distance between side of appliance and inside face of wall L1 in mm see fig 7.
3. Mark off and cut flue tubes following guidance show in fig 8 below. Flue tubes should be cut to length
TL in mm. Both inner and outer tubes should be cut flush with each other, square and any
burrs removed.
Where TL required, is greater than 845 mm, then additional lengths (as appropriate) of 80/125
concentric tube will be required to extend the standard wall terminal. A fall of 3˚is required along the
length of the flue towards the appliance.
Concentric Wall Terminals
945
610
850*
845
Standard Horizontal
Discharge Wall Terminal
(supplied with 80/125
Concentric 90ºbend and
wall bezel plates not
shown)
Horizontal Wall Terminal
With Extendable Vertical
Discharge (supplied with
80/125 Concentric 90º
bend and wall bezel plates
not shown)
* From 01/10/00
Note: 3˚fall towards appliance required if additional lengths are
used
ø125
ø80
ø125
ø80
Detail For Marking Out For
Cutting Flue Hole For Side Flue,
Room Sealed Horizontal
Arrangement
Cut Flue Hole
ø130mm
Line-Top of
Appliance Chassis
(3˚fall to
appliance)
231
170
Fig 9.
Side Outlet
170
L1
W
Plain
Section
Installed
Uppermost
Wall Bezel
Plates
Required Length
Cutting Line measure from
this point
TL (mm)
TL = W+L1+235mm
Fig 7.
Fig 8.

15
STRATA1
installation of standard wall terminal with
rear outlet
In order to determine the length of concentric tube required to correctly terminate a rear outlet
arrangement, the following procedure should be followed.
1. Measure wall thickness W in mm - see fig 10.
2. Mark off and cut flue tubes following guidance shown in fig 11 below.
Flue tubes should be cut to length TL in mm. Both inner and outer tubes should be cut flush with each
other, square and any burrs removed.
Where TL required, is greater than 845 mm, then additional lengths (as appropriate) of 80/125
concentric tube will be required to extend the standard wall terminal. A fall of 3˚is required along the
length of the flue towards the appliance.
13.0 room sealed flue installations (contd)
Rear Outlet
170
W
Fig 10.
Plain
Section
Installed
Uppermost
Wall Bezel
Plates
Required Length
Cutting Line measure from
this point
TL (mm)
TL = W+237mm
Fig 11.
170
c
L
cut flue hole
ø130
Fig 12.
Detail For Marking
Out For Cutting
Flue Hole For
Rear Flue, Room
Sealed Horizontal
Arrangement

16
STRATA1
13.0 room sealed flue installations (contd)
Extending the flue gas discharge vertically away
from a room sealed wall terminal.
The Strata 1 boiler is a fully condensing appliance with very low flue gas temperatures.
Consequently, the flue gas discharge is commonly seen as a white vapour plume, Whereas this is not
harmful when properly discharged into the atmosphere outside of a building from a correctly operating
appliance, the white vapour plume may cause, in certain applications a visual nuisance.
It must also be considered that a flue termination will drip condense water and may cause an ice hazard
below the terminal position
If it is considered that pluming or dripping from the end of a standard wall terminal may create a
nuisance, then as an alternative, the vertically extendable discharge wall terminal is available see figs 14 and
16. This creates a local room sealed intake for combustion air but allows the installer to extend the 80 mm
PPS flue gas tube to a point where pluming or dripping discharge will not cause a visual nuisance or hazard.
1. Lubricate male ends of concentric bend
with silicone grease and locate bend into
flue and air tube connection sockets on
the top of the boiler and gently push fully
home.
2. Slip flue tube and terminal assembly
through the prepared hole in the
outside wall.
3. Locate wall bezel plate loosely onto the
125mm rear tube
4. Lubricate male ends of concentric flue
tube and female sockets of flue bend
lightly with silicone grease. Insert
concentric tubes into bend and gently
push fully home. Ensure plain section of
external part of air inlet tube is located
uppermost.
5. Make good internally and externally gap between air tube and prepared hole through wall.
6. Slip on external wall bezel plate.
7. Fix internal and external wall bezel plates with fixings provided.
Where a flue terminal discharges through a wall is within 2m of ground level or balcony etc then
the terminal should be fitted with an appropriate sized terminal guard.
Installation of Vertical Discharge Wall Terminal
with side outlet
In order to determine the length of concentric tube required to correctly terminate a side outlet
extended vertical discharge arrangement, the following procedure should be followed.
1. Measure wall thickness W in mm - see fig 14 overleaf.
2. Measure distance between side of appliance and inside face of wall L1 in mm - see fig 14 overleaf.
3. Mark off and cut flue tubes following guidance shown in fig 15 overleaf. Flue tubes should be cut to
length TL in mm. Both inner and outer tubes should be cut flush with each other, square and any burrs
removed.
Where TL required, is greater than 610 mm, (*850mm) then additional lengths (as appropriate) of
80/125 concentric tube will be required to extend the vertical discharge wall terminal. A fall of 3˚is
required along the length of the flue towards the appliance.
method of assembly of horizontal concentric flue
system using standard wall terminal.
13
4
6
2
Fig 13.
Plain
Section
Uppermost

17
STRATA1
Installation of Vertical Discharge Wall Terminal
With Rear Outlet
In order to determine the length of concentric tube required to correctly terminate a rear outlet
extended vertical discharge arrangement, the following procedure should be followed.
1. Measure wall thickness W in mm - see fig 16.
2. Mark off and cut flue tubes following guidance shown in fig 17 below.
Flue tubes should be cut to length TL in mm. Both inner and outer tubes should be cut flush with each
other, square and any burrs removed.
Where TL required is greater than 610 mm, (*850mm) then additional lengths (as appropriate) of
80/125 Concentric tube will be required to extend the vertical discharge wall terminal. A fall of 3˚is
required along the length of the flue towards the appliance.
* available 01/10/00
Installation of Vertical Discharge Wall Terminal
With Side Outlet
Rear Outlet
Fig 16.
170
W
ø80 PPS
90ºBend
ø80
Bird Mesh
ø80
PPS Tube
Exhaust
Outlet
Installed
vertically
Upwards
on Some
Wall
Aspect
Wall Bezel
Plates
Fig 17.
Required Length
Cutting Line measure from
this point
TL (mm)
TL = W+262mm
Side Outlet
Fig 14.
170
W
ø80 PPS
90ºBend
ø80
Bird Mesh
ø80
PPS Tube
Exhaust
Outlet
Installed
vertically
Upwards
on Some
Wall
Aspect
Wall Bezel
Plates
Fig 15.
Required Length
Cutting Line measure from
this point
TL (mm)
TL = W+L1+260mm

18
STRATA1
See fig. 18
1. Lubricate male ends of concentric bend with silicone grease and locate bend into flue and air tube
connection sockets on the top of the boiler and gently push fully home.
2. Slip flue tube and terminal assembly through prepared hole in the outside wall.
3. Locate internal wall bezel plate loosely onto air tube.
4. Lubricate male ends of concentric flue tubes and female sockets of flue bend lightly with silicone
grease. Insert concentric tubes into bend and gently push fully home. Ensure flue gas discharge is
positioned vertically upwards.
5. Made good internally and externally gap between air tube and prepared hole through wall.
6. Fit external 2 piece wall bezel and secure both internal and external wall bezels using fixings
provided.
7. Seal air tube to exhaust discharge with a bead of silicone rubber mastic (mastic supplied) to create
weather seal to avoid entry of rain water into air tube.
8. Extend flue gas discharge to chosen position using 80 mm PPS flue tube fittings.
1
7
6
2
4
3
Extend using 80ø
PPS tube
Flue discharge
vertically upwards
on some wall aspect
8
Fig 18.
Method of assembly of extendable vertical
discharge wall terminal assembly.

19
STRATA1
14.0 examples of calculating
flue pressure loss
0
29
31
33
35
37
39
41
43
45
47
49
51
53
55
57
59
61
63
65
67
69
71
73
50 100 200150 250 300 350 400 450 500
Strata 1 - 75
Strata 1 - 60
Strata 1 - 45
0 2 6 10 14 18 22 26 30 34 38
0
10
30
50
70
90
110
130
20
40
60
80
100
120
140
48 1612 20 24 28 32 36 40
example 1
A Strata 1-60 boiler is installed with a concentric flue
system which takes an all horizontal route to a wall
terminal. Length of flue = 3m including one 90°bend.
Resistance =
3 x 1m length 80/125 concentric tube @ 8.5 Pa = 25.5
1 x 90°80/125 concentric bend @ 8.5 Pa = 8.5
1 x 80/125 concentric wall terminal @ 11.0 Pa = 11.0
Total Resistance = 45 Pa
conclusion: Total resistance is less than 100 Pa,
therefore, no alternative design required and no effect on
boiler output, or positioning required.
example 2
A Strata 1-45 boiler is installed with a concentric flue
system which takes a part horizontal, part vertical route
to a roof terminal with rain cap.
Length of horizontal section = 3m, vertical section =
12m, system includes 3x90°bends.
Resistance =
15 x 1m lengths 80/125 concentric tube @ 5.5 Pa = 82.5
3 x 90°80/125 concentric bend @ 5.5 Pa = 16.5
1 x 80/125 roof terminal @ 11.25 Pa = 11.25
Total Resistance - 110.25 Pa
Take into account that 12m of vertical (assume un-
insulated, as air for combustion direct from outside air
surrounds the flue gas tube) flue creates 20 Pa of
up-draught,
then final resistance = 110.25 - 20 = 90.25 Pa.
conclusion: Final operating resistance is less than 100
Pa, therefore, no alternative design required and no effect
on boiler output.
example 3
A Strata 1-75 boiler is installed (non room sealed) with a
proposed flue using DN 80 PPS single skin flue
components which takes a part horizontal, part vertical
route to a vertical open termination with bird mesh.
Length of horizontal section = 4m, length of vertical (un-
insulated) section = 11m with 4 x 90°bends,
and 2 x 45°bends.
Resistance =
15 x 1m lengths DN 80 PPS tube @ 8.0 Pa = 120
4 x 90°DN 80 PPS bends @ 8.0 Pa = 32
2 x 45°DN 80 bends @ 4.0 Pa = 8.0
1 x DN 80 open termination @ 8.0 Pa = 8.0
Total Resistance: 168 Pa
Take into account that 11m of vertical un-insulated flue
creates 18 Pa of up-draught, then final resistance would
be 168 - 18 = 150 Pa.
Reference to the graph of resistance effect on boiler
output shows the output would be reduced to
approximately 67kW. If this is unacceptable, then the
flue resistance must be re-calculated using a larger size
flue tube as shown below or consideration given to
moving the boiler position.
Re-calculating proposed flue installation using DN100.
15 x 1m lengths DN 100 PPS tube @ 3.0 Pa = 45
4 x 90°DN 100 bends @ 3.0 Pa = 12
2 x 45°DN 100 bends @ 1.5 Pa = 3.0
1 x DN 100 open termination @ 4.0 Pa = 4.0
Total Resistance: 64 Pa
Take into account thermal up-draught created (as before)
18 Pa. Therefore, operating resistance = 64 - 18 = 46 Pa,
with no effect on boiler output.
thermal up-draught when
flue gas temp 80°C and outside temp -5°C
effect of flue system resistance
on boiler output
Draught - Pa
Vertical Flue Lengths - metres
A = Insulated or within the building
B = Un-insulated and exterior to the building
A
B
Boiler Output kW at: Flow 80°C Return 60°C
Flue System Resistance - Pa

20
STRATA1
14.1 calculating
flue resistance
The excess pressure available for
overcoming the frictional resistance of a flue
system is 100 Pa.
The adjacent table of flue component
resistances will assist the designer in calculating
total flue system frictional loss.
If the total installed flue system resistance
exceeds 100 Pa., then the result will be a
reduction in boiler output. Reference to the
“Effect of Flue System Resistance On Boiler
Output”, graphs will assist. If the resistance of a
proposed flue system has an unacceptable
effect on boiler output, then a larger diameter
flue tube should be selected.
Thermal up-draught is generated in a
vertical flue system, reducing the resistance of
the system. Reference to the “Thermal Up-
draught Graph”will provide a figure in Pa.,
which may be deducted from the total
calculated flue system resistance.
NB. Thermal updraught does not apply to
horizontal sections of a flue system.
If a flue terminal is positioned within 2 m above ground level or any upper part of a building where
people have general access (e.g. balcony etc) then the terminal should be fitted with an appropriate guard.
The flue terminal of a Strata 1 boiler will plume heavily and care must be taken when selecting a
terminal position to ensure that a "nuisance situation" is not created.
Component Resistance P.a. 45 60 75
80/125 Concentric Wall Terminal 7.5 11.0 16.0
80/125 Concentric Roof Terminal Without Rain Cap 7.5 11.0 16.0
80/125 Concentric Roof Terminal With Rain Cap 11.25 16.5 24.0
1m length 80/125 Concentric Tube 5.5 8.5 12.0
93°80/125 Concentric Bend 5.5 8.5 12.0
45°80/125 Concentric Bend 2.75 4.25 6.0
80/125 Concentric To 2 x 80 Tubes Adaptor 4.0 6.0 10.0
1m length DN 80 PPS Tube Carrying Fluegas 5.0 7.5 11.0
1m length DN 80 PPS Tube Carrying Combustion Air 3.0 5.0 7.0
90°DN 80 PPS Bend Carrying Fluegas 5 7.5 11.0
90°DN 80 PPS Bend Carrying Combustion Air 3.0 5.0 7.0
45°DN 80 PPS Bend Carrying Fluegas 2.5 4.0 5.5
45°DN 80 PPS Bend Carrying Combustion Air 1.5 2.5 3.5
Room Sealed Chimney Cap DN 80 7.0 10.0 15.0
DN 80 x 100 PPS Increaser Piece-Fluegas or Air 1.0 1.0 1.0
90°DN 100 PPS Bend Carrying Fluegas 2.0 2.5 4.0
90°DN 100 PPS Bend Carrying Combustion Air 1.5 2.0 2.0
45°DN 100 PPS Bend Carrying Fluegas 1.0 1.3 2.0
45°DN 100 PPS Bend Carrying Combustion Air 0.8 1.0 1.0
1m length DN 100 PPS Tube Carrying Fluegas 2.0 2.5 4.0
1m length DN 100 PPS Tube Carrying Combustion Air 1.5 2.0 2.0
DN 80 Open Termination With Mesh 4.0 5.5 8.0
DN 100 Open Termination with Mesh 2.0 3.0 4.0
80/125 Concentric Wall Terminal With Vertical Discharge 7.5 11.0 16.0
80/125 To 100/150 Concentric Increaser 2.0 3.0 5.0
100/150 Concentric Wall Terminal 3.0 4.0 7.0
100/150 Concentric Roof Terminal 3.0 4.0 7.0
1m length 100/150 Concentric Tube 2.0 3.0 5.0
93°100/150 Concentric Bend 2.0 3.0 5.0
45°100/150 Concentric Bend 2.0 2.0 3.0
Boiler Model
15.0 flue
terminal positions
Flue Terminal Positions
Fig. 19
H,I
J
M
A
G
F D
E
P
Q
A
G
N
B,C
F
F
L
K
LK
N
M