RVR Energy Technology MICROMAT EC 45 Guide

3
index
Page Section
4 1.0 User Instructions
2.0 General Notes
6 3.0 Product Description
7 3.0 Product Description (contd)
8 4.0 Technical Data & Dimensions
9 5.0 Delivery Consignment/Unpacking The Boiler
6.0 Boiler Location
7.0 Installation Clearances
10 8.0 Wall Mounting
9.0 Gas Connection
11 9.1 Gas Conversion
12 10.0 System Flow & Return Connections
11.0 Condensate Connection
13 11.0 Condensate Connection (contd)
12.0 Flue Combustion Air Connection - General
14 13.0 Flue Systems
17 14.0 Calculating Flue Resistance
20 - 21 15.0 Ventilation Requirements Single Appliances
22 - 30 16.0 Hydraulic system Design (circuit diagrams)
31 16.1 Water Treatment System Cleaning
16.2 Care With The Use of Soldering Flux
17.0 Electrical Connections
32 - 41 17.0 Electrical Connections (contd)
41 18.0 Commissioning The MICROMAT EC Boiler
42 18.1 Pre-Commissioning Checks
43 18.2 Dip Switch Settings
44 18.3 First Firing
45 18.3 First Firing (contd)
45 - 47 18.4 Setting Weather Compensation
48 18.5 Setting Domestic Hot Water Temperature
18.6 Service Button/Setting Heating Output
49 18.6 Service Button/Setting Heating Output (contd)
18.7 Output For Charging Hot Water
19.0 Setting The Boiler To Work
30 20.0 Servicing Instruction
20.1 Inspection
51 20.2 Maintenance
52 - 54 21.0 Screen Display/Diagnosis Of Faults
21.1 Screen Display/Diagnosis Of Faults
21.2 (Possible) Causes Of Fault & Corrective Action

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1.0 user instructions for
the micromat boiler appliance
Before operating the boiler:
Check that the boiler has been installed in strict accordance with the instructions contained in this manual. Non
compliance with the instructions may result in injury and/or damage to property. The warranty on the boiler is void
if the boiler is not installed in accordance with these instructions.
Check the following points with the installer:
A suitable corrosion inhibitor has been added to the water in the system. (see page 31)
The water used to fill the system is within the purity limits specified. (page 31)
Any soldering fluxes used are compatible with the boiler (see page 31)
Important!
The Micromat EC boiler requires an annual service. The boiler display will display [Service] when a service is due
although the boiler will continue to operate normally. An RVR approved service technician should carry out the
annual service.
Switching ON the MICROMAT EC
1) Ensure the pressure gauge indicates a pressure within the system of not less than 0.5 bar and
not more than 3 bar.
2) Ensure the gas supply is turned on.
3) Switch on the on/off switch on the appliance control panel.
After switching on the boiler the MICROMAT EC operates automatically.
Switching OFF the MICROMAT EC
1) Switch off the on/off switch on the appliance control panel.
2) Turn off the gas supply
Turning off the boiler will leave the system at risk of freezing during the winter months and will disable the automatic
pump exercising routine. If the only reason for shutdown is that normal heating is not required, then it is recommended
to leave the boiler on and turn off or turn down any external controls.
Boiler Switch Panel
Display ECO/ECO
Plus Switch ON/OFF
Switch Water Pressure
RESET
Button
ENGINEERS
Button TEST Button

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1.0 user instructions for
the micromat boiler appliance
Functions of the Control Panel Buttons and Dials
Reset Button
This button has two functions
1. Resetting of fault conditions: - When the display text is flashing on and off, a boiler fault is indicated. The
type of fault is displayed on the screen. Please refer to the fault finding section on page 52 for a description
of these faults. The boiler control is reset by pressing the Reset button once.
2. Inspection of boiler operating parameters:- When the display is not flashing (ie when the boiler is in normal
operation), the Reset button may be used to inspect the boiler operating parameters.
Press once - Display shows “T1 Fl1 --°C” - This is the flow water temperature from heat exchanger 1.
Press twice - Display shows “T3 Fl2 --°C“ - This is the flow water temperature from heat exchanger 2.
Press three times - Display shows “T3 Ret --C” - This is the return water temperature to the boiler.
Press four times - Display shows “T5 Sto --°C” - This is the Domestic hot water storage temperature. A temperature
is shown only if the hot water temperature sensor (RVR Stock no: SBA021) is connected.
Press five times - Display shows “Fan Sp 1 ---- RPM” - This is the burner blower speed for heat exchanger 1.
Press six times - Display shows “Fan Sp 2 ---- RPM” - This is the burner blower speed for heat exchanger 2.
Press seven times - Display shows “Pump 1 --%” - This is the speed of the circulation pump as a percentage of
it’s maximum speed.
Press an eighth time and the display returns to normal displaying the supply water temperature.
Engineers Button
The user will not normally need to use this button. It is used by the service technician to enable measurement of
flue emissions even without heat requirement being present.
NOTE: This function will not be available if the MICROMAT EC and the heating system have reached their maximum
temperatures.
If the Engineers button is pressed once then the MICROMAT EC operates with half power. The display shows [Flue
Emissi]. If the Engineers button is not pressed again within 10 minutes the MICROMAT EC will switch back to
automatic operation after this period. Pressing the button again when [Flue-Emissi] is displayed brings [10min Low]
onto the display. In this condition the power output of the boiler can be adjusted using the green potentiometer
between 11kW and 57kW (EC62H) and 14kW and 72kW (E76H)
Turning it to the right : Less Power Turning it to the left: More Power
Pressing the Engineers button again while [10 min. low] is shown in the display switches the MICROMAT EC back
to automatic operation. After 10 minutes partial output the MICROMAT EC will return to automatic operation
TEST Button
The Test button is used to simulate the function of the hot water High Limit Stat.
Whilst theTEST-button is pressed the display shows [Limit F/R]. During this display the function of the MICROMAT
EC is blocked. When the button is released the boiler will return to normal operation.
If the button is pressed for more than 3 minutes [Wat 1 Lockout] will blink on the display. The function of the
MICROMAT EC is then locked.
The MICROMAT EC can also be locked by simultaneously pressing the TEST and ENGINEERS button.
When the RESET button is pressed again the MICROMAT EC returns to automatic operation.
ECO and ECO PLUS Operation
In ECO PLUS mode the pumps in the MICROMAT EC maintain a temperature differential of 20K (10K with underfloor
heating) if the system design allows this. This ensures the most effective use of energy.
In ECO mode the temperature differential is only regulated if the return temperature exceeds 50°C. With lower
temperatures the pumps work at full speed. This also ensures the maximum heat dissipation. The ECO mode setting
is recommended if individual rooms do not get warm enough and hydraulic balancing is not possible.
Green Potentiometer
The green potentiometer is used to adjust the Domestic hot water storage temperature, if the boiler has been
configured for this. See page 48 for more information.
Red and Blue potentiometers
These are used to alter the weather compensation settings. See page 45 for more information.

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2.0 general notes
3.0 product description
These instructions are intended to assist the installer, commissioning engineer, maintenance engineer and user
with the installation, maintenance and usage of MICROMAT EC,45, 62 and 76 models gas fired condensing boilers.
Please read this manual fully before commencing the installation of the appliance. The MICROMAT EC must only
be installed by persons deemed to be competent. This manual must be handed to the user following completion
of the installation.
The MICROMAT EC 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 MICROMAT EC 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 MICROMAT EC 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 88%
gross (96% nett) at 60°C return temperature, up to 96% gross (104% 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 a one to
one ratio of precisely measured volumes of fuel to air, this allows extremely accurate and instant variable burner
output control to be achieved.

3.0 product description
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energy saving
In addition to the extremely efficient burner and heat exchanger system employed in the MICROMAT EC each
appliance includes a modulating speed boiler primary pump. 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%.
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, HWS primary pump or diverter valve and an underfloor circuit mixing valve and
pump, plus the ability for the boiler to be controlled by a remote multi function modulating room
unit. Multiple boilers may be connected to a modulating Kaskade manager 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 125/70 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 MICROMAT EC 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 provided that
INIBAL corrosion inhibitor is used in the system and a service contract is in place with an RVR approved
service agent. Please contact the RVR Customer Care Department for details.

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4.0 technical data & dimensions
underside - models 45/62/76
plan - models 45/62/76
238
229
108
458
38
55
231
435
1 2 3 4
193
108
38
24
35
55
125678
front - all models
950
50
CONNECTION MICROMAT EC 45 62 76
1. Return 1 1/4” BSP-M 11/4” BSP-M 11/4” BSP-M
2. Flow 1 1/4” BSP-M 11/4” BSP-M 11/4” BSP-M
3. Flue Gas (OD) 70mm 70mm 70mm
4. Air Duct (OD) 125mm 125mm 125mm
5. Condense Siphon Cleaning 3/4” BSP 3/4” BSP 3/4” BSP
Point (capped)
6. Condensate 3/4” BSP-M 3/4” BSP-M 3/4” BSP-M
7. Cable Entries Multiple Grommets
8. Gas 3/4” BSP 3/4” BSP 3/4” BSP
MODEL MICROMAT EC 45 62 76
Nominal Heat Input Nett (max) kW 43 57 72
Nominal Heat Output 80/60°C kW 41.3 55.8 70.6
Nominal Heat Output 50/30°C kW 45.2 60.4 76.0
Input Rate Nat Gas (max) m3/h 4.5 6.01 7.6
Minimum/Maximum Gas Pressure mbar 15/60 15/60 15/60
Flue Gas Volume (hot) m3/h 64 81 104
Pressure at Flue Outlet pa 100 100 100
Maximum Working Pressure bar 3.0 3.0 3.0
Minimum Working Pressure bar 0.5 0.5 0.5
Maximum Flow Temperature °C 85 85 85
Power Supply Volts 230 230 230
Fuse rating Amps 3.0 3.0 3.0
Average Power Consumption Watts 115 115 164
Water Content Litres 6 7 8
Weight (Dry) kg 64 69 73

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6.0 boiler location
7.0 installation clearance
5.0 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, 1 Nr 3/4” BSP
Inlet x 1” BSP outlet safety valve set 3.0 bar, 1 Nr 3/4” x 1/2” BSP reducing nipple (for safety valve inlet) and
1 Nr outside air temperature sensor.
To unpack the boiler, the carton should be laid on the floor with the top carton seam uppermost. Carefully remove
tape from seam and open carton flaps, remove packing material, wall mounting bracket and fittings carton. For ease
of boiler handling from the carton it is suggested that the carton be slit down each corner and the carton sides laid
out flat. The boiler should only be lifted by contact with the rear (grey) chassis assembly.
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.
The MICROMAT EC 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 condensate drain nearby or an alternative is to install a condensate sump receptacle
and condensate disposal pump which should remove the condensate 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: I987 or BS6644: 1991.
For ease of installation, commissioning and maintenance the following minimum clearances should be observed.
Sides 50mm
Above 250mm
Below 150mm
Front 450mm

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9.0 gas connection
8.0 wall mounting
fig. 1
fig. 2
The MICROMAT EC boiler mounts to the wall via a
wall mounting bracket which interlocks to a rail on the
rear of the boiler. The wall mounting bracket should be
firmly fixed to the wall using suitable fixings with a
countersunk head. 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 NOT lift the
boiler by the internal parts of the appliance.
important
When viewed from the side, the 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.
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 1mbar from the meter
to the appliance. The nominal inlet working gas pressure
measured at the appliance should be 20.0 mbar for
Nat. Gas and 37 mbar for LPG.

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9.1 gas conversion
The MICROMAT EC is factory fitted for Natural Gas (G20). However the unit can easily be converted to LPG (G31)
by using the kit supplied (part no. 251588) and following the instructions below.
• Remove cover from boiler
• Open the outlet flange joints at the gas combi valves.
• On the outlet side of the gas combi valve add the Ø 5.7mm LPG jets from the conversion kit.
• On the inlet side of the left hand gas combi valve only, replace the NG jet with the 3.5mm LPG Prejet.
• Re-tighten the flange joint. Do not forget the O-rings.
• Check for Leakage.
• On the MICROMAT EC 45 H/62 H/76 H, when converting to LPG, the front bore on both gas/air mixing
chambers must be closed using the black ø10mm plugs supplied in the conversion kit.
• In addition, with the MICROMAT EC 76H both back bores in both gas/air mixing chamber must be closed
using the Ø15mm plugs supplied in the conversion kit.
Enter the gas type to which the MICROMAT EC is converted on the label next to the type label

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10.0 system flow & return connections
11.0 condensate connection
Note The MICROMAT EC boiler must only be installed on sealed and pressurised systems. The maximum working
pressure of the boiler = 3 bar. A safety valve set to 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 11/4” 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 11/4” 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 connections
are to the top of the appliance) to install drain cocks.
The appliance is supplied with 2Nr 11/4” x 11/4” 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 drain cock.
The flow and return pipework should include isolation valves and a method of disconnection local to the boiler
The condensate connection is located at the underside rear of the appliance see fig 5.
The condensate 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 condensate connection is a 3/4” BSP Male threaded stub fabricated from plastic.
The installer must connect to this stub, a condensate pipe fabricated from plastic tube and fittings (3/4”, 22mm,
overflow pipe is considered suitable). Copper tube must not be used for the condensate pipe! The condensate
pipe must fall continuously from the appliance to a suitable nearby drain.

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11.0 condensate connection
12.0 flue/combustion
air connection general
If any part of the condensate 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 condensate is not available nearby to, and below the boiler (e.g. boiler installed
in a basement below ground level location), then a suitable condensate sump receptacle with a discharge pump
should be installed below the boiler to remove the condensate to a remote drain.
When making the condensate 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 condensate outlet assembly.
It is recommended that the condensate pipework should include a method of disconnection and cleaning points.
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 70mm flue gas connection centrally within the 125mm air inlet
connection.
There are two options for flueing the MICROMAT EC 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 70/125 components where air for combustion is taken from outside of the
building. When using a room sealed flue, whereas 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
For detail and advice on common flues serving multiple boilers, contact RVR Ltd.
Important Note
Where the MICROMAT EC 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.

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13.0 flue systems
The MICROMAT EC has an excess pressure combustion system that allows the appliance to be exhausted over
extended distances using small OD flue components.
The flue gas temperature is extremely low (typically the same as the flow water temperature), which allows the use
of easy to install PPS (polypropylene) flue pipe and fittings.
The appliance can take combustion air from the room in which it is installed (conventional application) or can be
room sealed using a concentric flue arrangement of a 70mm PPS flue duct within a 125mm galvanised metal air
duct, finished in off-white RAL 7035. A full range of flue pipe and air duct components including roof and wall
terminals is available from RVR Limited.
Flue System Option No. 1
Horizontal Balanced Flue System
Using this sytem the air for combustion and the flue products are piped
to/from outside the space.
The balanced flue may pass through the wall directly behind, or, on either
side of the MICROMAT EC.
The following components and options are available from RVR Limited:~
•70/125 concentric wall terminal set complete with flue products sampling
tee, 500mm straight concentric flue, wall sealing plates and outside terminal.
These are finished in RAL 7035 (the 125mm galvanised pipe) and light grey
(natural colour of 70mm PPS pipe). RVR Order Code - SBA050
The system may be extended using the following accessories:
•125mm Ø Extension pipe RAL7035, 250mm long. RVR Order Code - SBA053
•125mm Ø Extension pipe RAL7035, 500mm long. RVR Order Code - SBA054
•125mm Ø Extension pipe RAL7035, 1000mm long. RVR Order Code - SBA055
•125mm Ø 90°bend RAL7035. RVR Order Code - SBA056
•70mm Ø Extension Pipe PPS, 250 mm long. RVR Order Code - SBA057
•70mm Ø Extension Pipe PPS, 500mm long. RVR Order Code - SBA058
•70mm Ø Extension Pipe PPS, 1000mm long. RVR Order Code - SBA059
•70mm Ø 90°bend PPS. RVR Order Code - SBA060
•Birdscreen for 70mm Pipe. RVR Order Code - ACB002
Concentric Wall Terminal Set
Order Code SBA050
Flue Products
Sampling Tee.
MICROMAT EC
Horizontal Balanced Flue with side exit Concentric Wall Terminal Set
Order Code SBA050.
Flue Products
Sampling Tee.
MICROMAT EC
Horizontal Balanced Flue with rear exit

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15
Flue System Option No. 2
Vertical Balanced Flue System
Using this system the air for combustion and the flue products are piped vertically to/from outside the space.
The balanced flue may exit through both flat and pitched roofs. Suitable flashings are available for either case.
The following components and options are available from RVR Limited:
•70/125 concentric roof terminal set, complete with concentric pipes and terminal. The air pipe is finished in black
PPS and the flue pipe in grey PPS. The length is 1150mm. RVR Order Code - SBA051
•70/125 concentric roof terminal set, complete with concentric pipes and terminal. The air pipe is finished in black
PPS and the flue pipe in grey PPS. The length is 2000mm. RVR Order Code - SBA061
•Flue Products Sampling Tee (RAL 7035). RVR Order Code - SBA052 (Note: This item must be used with either
of the above kits)
•Pitched Roof Flashing (20°- 45°). RVR Order Code - SBA062
or
• Flat Roof Flashing. RVR Order Code - SBA063
The system may be extended using the following accessories:
•125mm Ø Extension Pipe, Black PPS, 1020mm long. RVR Order Code - SBA064
•125mm Ø Extension Pipe, Black PPS, 2000mm long. RVR Order Code - SBA065
•70mm Ø Extension Pipe, Grey PPS, 1000mm long. RVR Order Code - SBA059
•70mm Ø Extension Pipe, Grey PPS, 2000mm long. RVR Order Code - SBA066
•45°Bend Black PPS, Male and Female Connections. RVR Order Code - SBA067
•45°Bend Black PPS, two Female Connections. RVR Order Code - SBA068
•70mm Ø 90°bend PPS. RVR Order Code - SBA060
MICROMAT EC
Flue Products
Sampling Tee
(RAL 7035)
Order Code
SBA052
Vertical Balanced
Flue Kit (Black PPS)
Order Code
SBA051/ SBA061
(1150mm/2000mm)
Flat Roof Flashing
Order Code SBA063
Vertical Concentric System (Flat Roof)
Vertical Concentric System (Pitched Roof)
Pitched Roof
Flashing 20°-45°
Order Code
SBA062
Vertical Balanced
Flue
Kit (Black PPS)
Order Code
SBA051/SBA061
(1150mm/2000mm)
Flue Products
Sampling Tee
(RAL 7035)
Order Code
SBA052
MICROMAT EC

13.0 flue systems
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Flue System Option No. 3
Horizontal Discharge with air for Combustion taken from Room.
Using this sytem the air for combustion is taken in from the room at the sampling Tee and the flue products
are exhausted horizontally through a wall.
This sytem comprises :
• Flue Products Sampling Tee (RAL 7035). RVR Order Code - SBA052 (This must always be used)
• 70mm Ø Extension Pipe, Grey PPS, 1000mm long. RVR Order Code - SBA059
The system may be extended using the following accessories:
• 70mm Ø Extension Pipe PPS, 250 mm long. RVR Order Code - SBA057
• 70mm Ø Extension Pipe PPS, 500mm long. RVR Order Code - SBA058
• 70mm Ø Extension Pipe PPS, 2000mm long. RVR Order Code - SBA066
• 70mm Ø 90°bend PPS. RVR Order Code - SBA060.
• Birdscreen for 70mm Pipe. RVR Order Code - ACB002.
MICROMAT EC
70mm Ø 90°
Bend Grey PPS
Order Code
SBA060
70mm Ø Grey
PPS Pipe
500mm long
Order Code
SBA058
70mm Ø Grey
PPS Pipe
250mm long
Order Code
SBA057
70mm Ø Grey
PPS Pipe
250mm long
Order Code
SBA059
Flue Products
Sampling Tee
Order Code
SBA052
Horizontal discharge with air for Combustion taken from Room

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14.0 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 up-draught does not apply to horizontal sections of a flue system.
COMPONENT RESISTANCE (Pa) 45 62 76
70/125 Concentric Wall Terminal 14.6 21.4 31.2
70/125 Concentric Roof Terminal Without Rain Cap 14.6 21.4 31.2
70/ 125 Concentric Roof Terminal With Rain Cap 21.9 32.2 46.8
1m length 70/125 Concentric Tube 10.7 16.6 23.4
93°C 70/125 Concentric Bend 10.7 16.6 23.4
45°C 70/125 Concentric Bend 5.4 8.3 11.7
1m length DN 70 PPS Tube Carrying Fluegas 9.7 14.6 21.4
1m length DN 70 PPS Tube Carrying Combustion Air 5.8 9.7 13.6
90°DN 70 PPS Bend Carrying Fluegas 9.7 14.6 21.4
90°DN 70 PPS Bend Carrying Combustion Air 5.8 9.7 13.6
45°DN 70 PPS Bend Carrying Fluegas 4.9 7.8 10.7
45°DN 70 PPS Bend Carrying Combustion Air 2.9 4.9 6.8
Room Sealed Chimney Cap DN 70 13.6 19.5 29.2
DN 70 x 100 PPS Increaser Piece-Fluegas or Air 1.9 1.9 1.9
90°DN 100 PPS Bend Carrying Fluegas 3.9 4.9 7.8
90°DN 100 PPS Bend Carrying Combustion Air 2.9 2.9 3.9
45°DN 100 PPS Bend Carrying Fluegas 1.9 2.5 3.9
45°DN 100 PPS Bend Carrying Combustion Air 1.6 1.9 1.9
Im length DN 100 PPS Tube Carrying Fluegas 2.0 2.5 4.0
Im length DN 100 PPS Tube Carrying Combustion Air 1.5 2.0 2.0
DN 70 Open Termination With Mesh 7.8 10.7 15.6
DN 100 Open Termination with Mesh 2.0 3.0 4.0
70/125 To 100/150 Concentric Increaser 3.9 5.8 9.7
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 Flue gas 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 Flue gas 2.0 2.5 4.0

Energy Technology
Ltd.
18
14.0 calculating flue resistance
flue pressure loss
example I
A MICROMAT EC 62 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 70/125 concentric tube @ 16.6 Pa = 49.8
1 x 90°70/125 concentric bend @ 16.6 Pa =16.6
I x 70/125 concentric wall terminal @ 21.4 Pa = 21.4
Total Resistance = 87.6Pa
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 MICROMAT EC 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 = 1m, vertical section = 6m, system includes
1 x 90°bend.
Resistance =
7 x 1m lengths 70/125 concentric tube @ 10.7 Pa = 74.9
1 x 90°70/125 concentric bend @ 10.7 Pa= 10.7
1 x 70/125 roof terminal @ 21.9 Pa = 21.9
Total Resistance = 107.5 Pa
Take into account that 6m of vertical (assume uninsulated, as air for
combustion direct from outside air surrounds the flue gas tube) flue creates
10 Pa of up-draught,
then final resistance = 107.5 - 10 = 97.5 Pa.
conclusion: Final operating resistance is less than 100 Pa, therefore,
no alternative design required and no effect on boiler output.
example 3
A MICROMAT 1-75 boiler is installed (non room sealed) with a proposed
flue using DN 70 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 (uninsulated) section
= 11m with 4 x 90°bends, and 2 x 45°bends.
Resistance =
15 x 1m lengths DN 70 PPS tube @ 21.4 Pa = 321
4 x 90o DN 70 PPS bends @ 21.4 Pa = 85.6
2 x 45o DN 70 bends @ 10.7 Pa = 21.4
1 x DN 80 open termination @ 15.6 Pa = 15.6
Total Resistance: 443.6 Pa
Take into account that 11m of vertical uninsulated flue creates 18 Pa of
up-draught, then final resistance would be 443.6-18 = 425.6 Pa. Reference
to the graph of resistance effect on boiler output shows the output would
be reduced to approximately 59kW. 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 DN 100.
15 x 1m lengths DN 100 PPS tube @ 3.0 Pa = 45
4 x 90o DN 100 bends @ 3.0 Pa = 12
2 x 45o 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.
Vertical Flue Lengths - metres
Draught - Pa
thermal updraught when flue gas
temp 80°C and outside temp -5°C
A = Insulated or within the building
B = Uninsulated and exterior to the building
A
B
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
MICROMAT EC76
MICROMAT EC 62
MICROMAT EC 45
29
31
33
35
37
39
41
45
47
49
51
53
55
57
59
61
63
65
67
69
71
73
43
0 50 150 200 250 300 350 400 450500100
effect of flue system resistance on boiler output
Boiler output kW at: flow 80°C Return 60°C
Flue System resistance - Pa

19
14.0 calculating flue resistance
Energy Technology
Ltd.
15.0 flue terminal positions
Minimum dimensions of flue terminal positions see fig 19 below.
Dimension Terminal Position Balanced flue room sealed (mm) Non room sealed (mm)
A Directly below an opening, 300mm 300mm
air brick, windows etc.
Not Recommended.
B Below gutters, soil pipes or 75mm 75mm
drain pipes
C Below eaves 200mm 200mm
D Below balconies or car port 200mm 200mm
roof. Not Recommended But installation But installation
not recommended not recommended
E From vertical drain pipe or 75mm 75mm
soil pipe
F From an internal or external 300mm 200mm
corner
G Above ground, intersecting 300mm 300mm
roof or balcony level
H From a surface facing the 2000mm 2000mm
terminal
I From a terminal facing the 2000mm 2000mm
terminal
J From an opening in the car 1200mm 1200mm
port (e.g. door, window) into But installation But installation
dwelling not recommended not recommended
K Vertically from a terminal on 1500mm 1500mm
the same wall
L Horizontally from a terminal 300mm 300mm
on the same wall
M From the wall on which the N/A 50mm
terminal is mounted.
N From a vertical structure 500mm N/A
on the roof
P Above intersection with roof 500mm 150mm
The flue terminal of a MICROMAT EC boiler will plume
heavily and care must be taken when selecting a
terminal position to ensure that a “nuisance situation’
is not created
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.
Fig 19

20
15.0 ventilation requirements
single appliances
Energy Technology
Ltd.
The room or space in which the MICROMAT EC boiler is installed may require to be ventilated in accordance with
BS5440: Part 2:1989 or BS 6644: 1991 as appropriate to the boiler input.
The following tables must be read to ascertain the amount of ventilation required.
Table 1 Room Installation - Non Room Sealed Flue.
Natural Ventilation Direct to Outside Air
Boiler Model Ventilation Openings Free Area cm2
High Level Low Level
MICROMAT EC 45 196 Position Not Dictated
MICROMAT EC 62 278 555
MICROMAT EC 76 319 637
Table 2 Room Installation - Non Room Sealed Flue.
Natural Ventilation From Adjacent Room
Boiler Model Ventilation Openings Free Area cm2
MICROMAT EC 45 196cm2with adjacent room similarly ventilated direct to outside air.
MICROMAT EC 62 & 76 Ventilation from adjacent room not permitted see Table 1 for ventilation
area direct to outside air.
Table 3 Room Installation – Room Sealed Flue
There are not specific requirements for a room to be ventilated where the appliance
is room sealed. However, consideration should be given to providing ventilation for
general cooling, (BS6644 specifies room temperature limits) and the following free
ventilation areas are recommended to be installed.
Boiler Model Recommended Natural Ventilation Free Area cm2
MICROMAT EC 45 196 cm2(if ventilated from adjacent room, then adjacent room must be equally ventilated
direct to outside air)
MICROMAT EC 62 253 cm2Direct to outside air.
MICROMAT EC 76 335 cm2Direct to outside air.
Table 4 Compartment Installation – Non room sealed flue Natural Ventilation Direct to
outside air
Boiler Model Ventilation Openings Free Area cm2
High Level Low Level
MICROMAT EC 45 227 454
MICROMAT EC 62 278 555
MICROMAT EC 76 319 637