MHS Boilers Regency Premix 70/6 Guide

REGENCY PREMIX
INSTALLATION, ADJUSTMENT AND SERVICING INSTRUCTIONS
FOR THE INSTALLER
USE AND MAINTENANCE INSTRUCTIONS
FOR THE USER
L261

Dear Customer,
May we thank you for having chosen a MHS Group product.
This manual has been prepared to acquaint you with the boiler you have purchased.
Please take time to read it, because the instructions and suggestions on the installation, use and
maintenance of your boiler will enable you to obtain the best results from our high quality product for
a very long time.
CONFORMITY STATEMENT
Regency Premix boilers are manufactured in accordance with the EN656 standard and carry the CE
mark. They comply with the following Directives:
990/396 Gas Appliances Directive
992/42 Boilers Efficiency Directive
973/23 Low Voltage Directive
989/893 Electro-Magnetic Compatibility
They comply with Gas Safety Regulations.
Regency Premix boilers are classified as type B23 (the combustion air is coming from the room where
the boiler is installed, there is no draught diverter and the burner fan is placed upstream the
combustion chamber), and are designed for use on gas category I2H (natural gas).
The Manufacturer will not assume any responsibility for the non-observance of any relevant statutory
installation requirements, regulations and codes of practice, or any recommendations and instructions
included in this manual.
INSTALLATION REQUIREMENTS
The equipment must be installed by competent personnel who are suitably qualified in the geld of civil
heating systems.
The boilers need to be connected to:
9a supply gas system
9a supply electric system
9an hydronic heating system
9a natural draught chimney
The installation of Regency Premix boilers must be in accordance with relevant statutory requirements,
the 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 Byelaws, Local Gas Undertaking Regulations, Local & National Water Byelaws, Fire Authority
Regulations and Insurance Company requirements.
The following codes of practice are also applicable:
9BS6880 Codes of practice for low temperature hot water heating systems of out-put greater than 45
kW. Parts 1,2 & 3 : 1988.
9CP342 Code of practice for centralised hot water supply, part 2 Buildings other than individual
dwellings.
9BS6644 1991 specification for gas fired hot water boilers of rated inputs between 60 kW and 2 MW.
9IGE/UP/2 Gas installation pipework, boosters and compressors on industrial and commercial
premises.
9CIBSE Guide Reference sections B7, B11 and B13.
9BS5440 Installation of flues and ventilation for gas appliances of rated input not exceeding 60 kW.
9British Gas IM/11 Flues for commercial and industrial gas fired boilers and air heaters.

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GUIDE TO CONTENTS
1 DESCRIPTION OF THE APPLIANCES......................................................................................................... 5
1.1 GENERAL REMARKS 5
1.2 BOILER MODELS 5
1.3 DIMENSIONAL DRAWINGS AND LIST 6
1.4 TECHNICAL DATA 7
1.5 EXPLODED VIEW OF THE BURNER AND PARTS LIST 8
1.5.1 BURNER DRAWINGS.............................................................................................................8
1.5.2 BURNER PARTS LIST.............................................................................................................9
1.6 EXPLODED VIEW OF THE BOILER BLOCK AND CASING 10
1.6.1 BOILERS DRAWING ............................................................................................................10
1.6.2 BOILERS PARTS LIST..........................................................................................................11
1.7 CONTROL PANEL 12
1.7.1 SERVICE DISPLAY INDICATIONS DURING OPERATION ..........................................................13
1.7.2 SERVICE DISPLAY INDICATIONS IN LOCK-OUT SITUATION....................................................13
2 INSTALLATION, ADJUSTING AND SERVICING INSTRUCTION – FOR THE INSTALLER .......................... 14
2.1 BOILER ROOM 14
2.2 UNPACKING 14
2.3 INSTALLATION OF THE BOILER 14
2.3.1 BOILER BODY POSITIONING AND ASSEMBLY........................................................................14
2.3.2 BURNER ASSEMBLY ............................................................................................................14
2.3.3 CASING ASSEMBLY.............................................................................................................14
2.3.4 CONDENSATE DISCHARGE CONNECTION .............................................................................15
2.3.5 WATER CONNECTION.........................................................................................................15
2.3.5.1 WARNINGS ABOUT THE WATER CIRCUIT. ...................................................................16
2.3.6 GAS CONNECTION..............................................................................................................16
2.3.7 FLUE CONNECTION ............................................................................................................16
2.3.8 ELECTRICAL SUPPLY AND CONNECTIONS.............................................................................17
2.3.8.1 WARNINGS................................................................................................................17
2.3.8.2 CONNECTIONS TO DO..................................................................................................17
2.3.8.3 OPTIONALS..................................................................................................................17
2.3.8.4 WIRING DIAGRAM – Regency Premix 70......................................................................18
2.3.8.5 WIRING DIAGRAM – Regency Premix 100 ....................................................................19
2.4 ADJUSTMENTS 20
2.4.1 BURNER COMMISSIONING AND STARTING UP......................................................................20
2.4.2 BOILER SETTINGS..............................................................................................................21
2.4.2.1 FLOW TEMPERATURE SETPOINT WITHOUT THE OUTSIDE SENSOR .................................22
2.4.2.2 FLOW TEMPERATURE SETPOINT WITH THE OUTSIDE SENSOR........................................22
2.5 SERVICING 22
2.5.1 PERIODIC OPERATIONS......................................................................................................22
2.5.2 FAULT FINDING..................................................................................................................23
2.5.2.1 DISPLAY PANEL LOCK OUT CODES.................................................................................23
2.5.2.2 FAULT FINDING FLOWCHART........................................................................................24
3 BOILER USE AND MAINTENANCE – FOR THE USER................................................................................ 25
3.1 GUIDANCE FOR THE USER 25
3.2 SWITCHING THE BOILER ON AND RUNNING 25
3.3 SWITCHING THE BOILER OFF 25
3.4 MAINTENANCE 25

- 5
1DESCRIPTION OF THE APPLIANCES
1.1 GENERAL REMARKS
Regency Premix boilers consist of a range of 2 models of gas fired cast iron sectional boilers, offering
high efficiency and very low emissions.
Cast iron Heat Exchanger.
Each cast iron sectional heat exchanger comprises:
9one front section
9a variable number of intermediate sections
9one special intermediate section
9one rear section.
All the sections are connected one to each other by means of bi-conical nipples.
Burner.
Each boiler is fitted with a special designed - fan assisted - fully premixed - modulating - gas burner
system, suitable for operation with natural gas.
This burner system is the result of an assembly of the following parts:
9A stainless steel burner-head, partially covered by a special metallic alloy matrix, high resistant to
heat;
9A fan placed before the combustion chamber, equipped with a fully modulating electronic fan-speed
control;
9An air-gas ratio control system, including a 1:1 gas valve and a venturi placed upstream the fan.
Boiler Management Unit.
The boiler is equipped with a Boiler Management Unit, with the following functions:
9Burner safety control
9Boiler temperature control through up to four NTC sensors, monitoring: flow, return, outside
temperature and, if required, DHW temperature;
9Other system devices control, such as DHW three valve.
It includes a display unit with push buttons and digital display (for the temperatures and the burner
status), to directly operate and control the boiler.
The access to the display unit is made possible by the rotation of the plastic cover on the up-front of the
boiler.
Special features.
Following the EU Efficiency Directive, the boilers are classified as LOW TEMPERATURE BOILERS. This
means that the boilers can run with a return water temperature between 35°C and 40°C,
continuously, giving rise to a certain condensate production during normal operation, depending on
the modulation ratio, so depending on the heating system demand (see the following 2.3.4).
1.2 BOILER MODELS
Nominal heat output
Model/number of sections kW
Part No. Gas Nat
Regency Premix 70/6 68,6 001616006
Regency Premix 100/8 99,9 001616008

1.3 DIMENSIONAL DRAWINGS AND LIST
REGENCY PREMIX REGENCY PREMIX
REARVIEW SIDEVIEW
BOILER MODEL L
[mm] Øg [mm] F & R [“] Øf [“]
Regency Premix 70/6 977 150 2 ¾
Regency Premix 100/8 1167 150 2 ¾
LEGEND
F = Water Flow
R = Water Return
Øg = Flue outlet
Øf = Gas connection
- 6

- 7
1.4 TECHNICAL DATA
Regency Premix 70/6 100/8
Nominal Heat Input
Q nom
Modulation down to Q MIN
kW
kW
75,0
44,8
109,5
65,2
Nominal Heat Output
P nom
P MIN corresponding to QMIN
kW
kW
68,6
41,2
99,9
60,0
Gas supply pressure
[mbar] 2H-G20 – Natural Gas 20 20
Gas rate (max/min)
(15°C, 1013mbar) 2H-G20 [m3/h] 7,9/4,7 11,6/6,9
Water content l 30 40
Max working flow temperature °C 85 85
Max working water pressure
PMS bar 5 5
Ø Flow/Return water connections “ 2 2
Water pressure drop
@ 10 K ∆T
@ 20 K ∆T
mbar
mbar
170
60
190
70
Gas connection “ ¾ ¾
Mass rate of combustion products
@ max input
@ min input
kg/s 0,034
0,022
0,050
0,032
Flue temperature
MAX INPUT @ CO2=9,0 & 80/60°C
water temp. Flow/Return
MIN INPUT @ CO2=8,5 & 50/40°C
water temp. Flow/Return
°C
158
88
164
93
NOXClass 5 5
Electrical supply ~ 230V (@ 50Hz)
75 W 80 W
Weight kg 268 351
Net Efficiencies:
Nominal Load (100%)
Partial Load (30%)
%
%
92,0
95,5
92,0
95,5
NOx Class (EN 656) 5 5

1.5 EXPLODED VIEW OF THE BURNER AND PARTS LIST
1.5.1 BURNER DRAWINGS
13
12
10
11
9
8b
8a
7
6
5
4
3
2
1
Re
g
enc
y
Premi
x
70
13
12
11
10 9 8b
8a
7
6
5
44
3
2
1
Re
g
enc
y
Premi
x
100
- 8

- 9
1.5.2 BURNER PARTS LIST
N. Description Regency Premix
70 Regency Premix 100
1 Burner Head - -
2 Adapter Flange - -
3 Back Plate - -
4 Electronics Module 001655577 001655576
5 Fan Unit 001655556 001655555
6 Gas Valve 001655579 001655578
7 Venturi 001655581 001655575
8a Electrode: ignition/surveillance 001655551 001655551
8b Electrode: earth 001655553 001655553
9 HT Connector 001655550 001655550
10 Electrode fixing bushing 001655569 001655569
11 Burner Head Gasket 001655561 001655560
12 Burner rear plate gasket 001655559 001655558
13 Burner assembly gasket 001655557 001655557

1.6 EXPLODED VIEW OF THE BOILER BLOCK AND CASING
1.6.1 BOILERS DRAWING
- 10

- 11
1.6.2 BOILERS PARTS LIST
N. Description Regency Premix
70 Regency Premix 100
1 Casing Side 001645426 right
001645436 left 001645428 right 001645438 left
2 Casing Top 001645446 001645448
3 Casing Main Door 001645411 001645411
4 Casing Bottom Door 001645412 001645412
5 Casing Main Door Bracket 001645982 right
001645983 left 001645982 right 001645983 left
6 Casing Control Panel Bracket 001645981 001645981
7 Casing Rear Fixing Bracket 001645953 001645953
8 Casing Front Fixing Bracket 001645953 001645953
9 Burner Mounting Plate Gasket 001666510 001666510
10 Burner Mounting Plate 001650000 001650000
11 Burner 001655500 001655510
11a Display PCB 001655571 001655571
12 Sight Glass 001646100 001646100
12a Comb. chamber pressure measuring 005546226 005546226
13 Gas Supply Tube 001651526
001651516 001651510
14 Water Distribution Pipe 001651506 001651508
15 Casing back panel 001645413 001645413
16 Flue outlet plate 001650010 001650010
17 Flue outlet gasket 001666511 001666511
18 Purging manifold 001651500 001651500
18a Automatic purging valve 001362101 001362101
18b Manual purging valve 008591303 008591303
18c Automatic anti-drain 008591316 008591316
19-20 Frame 001651000 001651000
21 Control panel plastic cover 001672200 001672200
22 Control panel bracket cover 001672200 001672200
23 Flue hood 001646006 001646008
24 Siphon 008591359 008591359
25 Casing side support 001645940 001645940
26 Boiler body
26a Front cast iron section 001630100 001630100
26b Intermediate cast iron section 001630600 001630600
26c Special Intermediate cast iron section 001630700 001630700
26d Rear cast iron section 001630900 001630900
26e Combustion chamber insulating blank 001666512 001666512
26f Combustion chamber steel plate 001645050 001645050

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1.7 CONTROL PANEL
8
125
4 7
36
15911
10 12 13 14
N. DESCRIPTION FUNCTION
1 LED indicator:
ON/OFF Power Supply This LED will be lit when the boiler is on. In the OFF mode a “-“ is shown in the STATUS
display.
2 LED indicator:
Central Heating Is lit when the boiler is in CH operation. This includes post-running of the pump over the CH
circuit. Once in the stand-by mode, the CH LED will go off again.
3 LED indicator:
Domestic Hot Water Is lit when the burner control is active because of DHW tapping. This includes the
programmed post-running time of the pump. When inactive, the DHW LED is switched off
again.
4 TEMPERATURE Display It consists of two 7-segment displays enabling a temperature up to 99 OC to be indicated.
The display will only show a temperature if the control is dealing with a heat demand. The
temperatures indicated are, respectively:
*hot water tank demand (S3 present) ÆSet-point flow temperature
* heat-up demand ÆNo temperature display
* DHW demand over plate heat exchanger ÆSet-point DHW temperature
* central heating demand ÆSet-point flow temperature
5 LED indicator:
Comfort mode ls lit when the boiler is set in the comfort mode. In this case, the Economy LED can never
be lit.
6 LED indicator:
Economy mode ls lit when the burner control is in Economy mode. In this case, the Comfort LED can never
be lit.
7 SERVICE Display It shows the operational status (see 1.7.1) when the boiler is in operation. In the stand-by
mode, the service display is switched off. If a lock-out appears, a code is shown (see 1.7.2).
8 LED indicator:
Lock-out Is lit when there is a lock-out situation; the Power Supply LED and SERVICE display will also
be lit. The temperature display and other LEDS will be off.
9 ON/OFF Power Supply button On: Heat demand enabled. Off: Any heat demands are disabled except for frost protection.
The display will only show “-“.
10 MODE button Press during operation to change temperature setpoint relevant to the LED indicator lit (CH
or DHW).
11 Change temperature setpoint
(down) Temperature setpoint is blinking and can be reduced digit by digit by pressing the button.
12 Change temperature setpoint
(up) Temperature setpoint is blinking and can be reduced digit by digit by pressing the button.
13 Economy/Comfort button Economy: The boiler is not pre-heated.
Comfort: The boiler is pre-heated.
14 SERVICE button Operates together other buttons only in case of adjusting or servicing.
15 RESET button Exit a lock-out situation.

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1.7.1 SERVICE DISPLAY INDICATIONS DURING OPERATION
Code Status description
0 Stand-by & pump overrun
1 Heat demand blocked
2 Flame simulation or ventilation
3 Ventilation + pre-ignition
4 Ignition
5 Central heating demand
6 Sanitary hot water demand
7 Heat-up
1.7.2 SERVICE DISPLAY INDICATIONS IN LOCK-OUT SITUATION
Code Status description
0 Safety thermostat open
0 Fuse F3 broken
0 Short-circuit NTC1 (Flow temperature sensor)
0 Short-circuit NTC2 (Return temperature sensor)
0 Interrupted contact NTC1 (Flow temperature sensor)
0 Interrupted contact NTC2 (Return temperature sensor)
1 Temperature NTC1 too high (Flow temperature sensor)
1 Temperature NTC2 too high (Return temperature sensor)
1 Temperature NTC3 (DHW temperature sensor) too high
Down-modulation to minimum load (CH demand)
2 Lock-out in running position (only CH & external DHW)
2 Flow and return sensor switched.
2 Flow temperature continuously lower than return temperature while running.
2 Flow and return not equal in stand-by
2 S3 > flow temperature while running
3 NTC1 increase too big (only active when CH in operation). ∆Tmax depends on
the size of NTCI, so the larger NTCI, the smaller ∆Tmax, and the sooner it will
intervene. Response: heat demand is blocked until the NTC1 and NTC2 increase
reaches 0. Lock-out after 10 blocks per heat demand for CH
4 No flame after ignition attempt
5 Flame off while running
6 Lock-out after 5 seconds.
lf the fan speed is at least 1 AI % this is considered ok if not the burner control
goes into lock-out alter 1 AK sec.
7 Parameters programmed
8,9,A Fan not running correctly
b Parameters test fail
C lf the gas valve is not in the correct position within 1 second.
d Gas valve test NOT OK
E Mains voltage control
F Software disturbance / EMC interference
H Parameter memory defect or Reset button defect or Multiplexer test.
When memory defect the display is not blinking!

- 14
2INSTALLATION, ADJUSTING AND SERVICING INSTRUCTION –
FOR THE INSTALLER
2.1 BOILER ROOM
The boiler must be installed in a non living room suitable and sufficient for good combustion, with
ventilation openings complying with the current local Regulations, including any national or
International Standards that may apply.
2.2 UNPACKING
The boiler is delivered in three packages:
9The heat exchanger, in a wooden crate
9The burner with accessories for the boiler, in a wooden crate
9The casing, in a carton
Remove all the packing material and inspect the equipment to ensure that all parts are present and
undamaged. If in any doubt, DO NOT USE THE EQUIPMENT. Instead, contact the supplier.
All packing materials should be stored or disposed off with care, as they may prove harmful to children
animals and the environment.
2.3 INSTALLATION OF THE BOILER
The following chapters describe in details how to execute the installation of the boiler. Please, follow
the exact train of phases.
2.3.1 BOILER BODY POSITIONING AND ASSEMBLY
1. Stand the boiler body on its steel trestle/outrigger.
2. Lay the boiler heat exchanger on a concrete base, possibly raised from the floor.
3. Be sure that any easily inflammable materials are at a minimum distance of 0,5 m.
4. Insert the water distribution pipe with its rubber gasket provided with the boiler in the backside
of the heat exchanger. Fix it with the M12 bolts provided on the pivots with the boiler body.
5. Assembly, with appropriate sealing on the thread, the tube provided with the purging valves at
the top of the rear section (opposite to water distributor).
2.3.2 BURNER ASSEMBLY
1. Insert the premix burner in the combustion chamber, passing the burner head through the hole
on the front metal plate.
2. fix it with the 4 bolts M10 provided on the pivots.
NB. The display board has to be assembled after having placed the casing on the boiler body (see
the last point of the next chapter).
2.3.3 CASING ASSEMBLY
1. fix the front (1) and rear (2) fixing side brackets with the bolts provided on the tie rods; the
front side bracket has the data plate stuck on
2. place sides (3) by introducing button holes on the bottom pins projecting from the base frame.
Fix sides with Ø3.5 self-tapping screws onto the fixing side brackets
3. place rear apron plate (4) between the sides, with bends oriented outside and fix it to the sides
with N. 6 Ø3.5 self-tapping screws
4. place panel bracket (5) by insert the lower buttonholes in the hinge pins; fix it on the fixing sides
bracket with N. 2 Ø3.5 self-tapping screws, by placing its extremity edge on top of it
5. assemble the two panel bracket covers (6), taking care that pins must be oriented inside and
thicker edge upside
6. assemble the bottom door (7) by inserting pins in its holes and shift down the door in order to
obtain a fixed position
7. assemble the main door brackets (8) on the main door (9) and fix it with N. 2 Ø3.5 self-tapping
screws for each bracket
8. insert the main door brackets between sides, taking care that the hinge pin is correctly placed in
the rabbet of the bracket. Carry the main door in closed position and fix it with safety screws
9. assemble the top casing (10), by introducing the pins in their seat

10. assemble plastic door (11) over the control panel on the panel bracket, locking it by pushing the
fork on the hinge pin. The opening must came from the bottom upwards.
11. Assemble the display board (12) under the control panel, using the bolts already fitted on the
four pivot.
2.3.4 CONDENSATE DISCHARGE CONNECTION
Fill with water the siphon delivered with the accessories and fit at the rear bottom of the stainless
steel flue hood.
Make the connection from the condensate discharge outlet with an open connection to the sewer
trunk line, following the local regulations in force.
2.3.5 WATER CONNECTION
The connection of the boiler to the water system should comply with all appropriate regulations.
When the boiler is filled in with water for the first time, make sure that the air is perfectly purged: use
the manual purging drain cock placed on the rear top side of the boiler body, on the purging manifold.
- 15

2.3.5.1 WARNINGS ABOUT THE WATER CIRCUIT.
-Set the water pressure in the boiler at least at 1,5 bar.
-The water circulation in the boiler must be always guaranteed by means of a pump;
THIS PUMP HAS TO BE PLACED ON THE RETURN, otherwise you can have risks of
overheating and calcareous scaling problems. The water flow rate in the boiler must ensure a flow-
return ∆T between 5K and 30K. This is valid particularly for each boiler of a cascade installation.
-Dirty in water can cause serious problem to the boiler structure, because such material can close
the water distributor holes, than an over-temperature in top of the boiler can occur. So, make sure
that the circuit water is clean, if necessary by means of adequate filters or vertical LOW LOSS
HEADER. This second solution allows also to separate the boiler circuit from the uses circuit.
-In the case of installations in known hard water areas (hardness greater than 20 French
degrees) or in an heating system were leakages are suspected, appropriate treatment of the
system fill water is REQUIRED.
L1
D1
D3
D2
D4
L1
L2
D2
L2
H
D1
H
3/4"F
x
20
1/2"Fx 20
3/4"M
1/2"Fx 20
3/4"F
x
20
1/2"Fx 20
3/4"M
1/2"Fx 20
D5 D5
-If, possible, install the right-settled pressure safety valve following the system calculation on the
tube provided with the purging valves at the top of the rear section
-If there is a need to treat the water with an anti-freeze agent, then carefully follow the
recommendations of the anti-freeze supplier/manufacturer, especially when mixing water with the
antifreeze.
2.3.6 GAS CONNECTION
Suitably qualified and competent personnel should carry out the gas train installation.
The gas connection should comply with relevant requirements of Gas Safety (Installation and Use)
Regulations.
Always include a manually operated shut-of/valve in the gas train when carrying out the installation.
This is required to isolate the burner for maintenance and servicing requirements, or for when the
burner is taken out of use for prolonged periods.
Before commencing the installations ensure that the gas supply is turned off and that all electrical
supplies to the burner are also disconnected.
Gas supply pipework should be fitted in accordance with CP.331/3, taking into account the size of the
boiler (see technical data § 1.4).
2.3.7 FLUE CONNECTION
The boiler should be connected to the a natural draught chimney with rigid flue pipes and fittings,
constructed and dimensioned according to the Local Regulations in force.
- 16

- 17
2.3.8 ELECTRICAL SUPPLY AND CONNECTIONS
2.3.8.1 WARNINGS
Suitably qualified and competent personnel should carry out the electrical installation. Before
commencing the installations ensure that all electrical supplies to the boiler are disconnected and that
the gas supply is turned off.
You must always comply with the basic safety and electrical regulations that are in force when carrying
out the electrical installation of the burner. This includes Statutory regulations and National and
International Standards where they apply.
It is vital that all safety requirements are met. In case of any doubt, ask for an accurate inspection of
the electrics by suitably qualified and competent personnel, since the manufacturer cannot be held liable
for damages that may be caused by failure to adequately earth the bunter.
Suitably qualified and competent personnel must also inspect the system to ensure that it is adequate to
take the maximum power used by the boiler as shown on the boiler data plate. In particular ensure that
the apply input cable cross-section is adequate for the power demand of the boiler.
The use of adapters, multiple outlet sockets and/or extension cables to connect the burner to the
electrical mains is NOT permitted.
An omnipolar disconnection system must be incorporated into the fixed wiring that provides a contact
separation of at least 3mm in all poles.
Always provide a magneto-thermal differential switch in the circuit that or be connected to the mains
supply.
Always ensure that equipment is connected to a right dimensioned earthing system, to avoid safety and
EMC problems.
2.3.8.2 CONNECTIONS TO DO
Connections need to be made to:
-the earth connection from the boiler body to the earth screw on burner mounting plate (with cable
supplied, already fixed to the fixing side bracket).
-the supply Live, Neutral and Earth (on the 7-way connector with the cable supplied). The supply
cable must be inserted and fixed in the gland provided on the side casing front fixing bracket and
then passed through the bushing on the side casing rear fixing bracket.
-The flow and return sensors (the sensors are supplied separately, in the boiler block packaging).
The electrical connection has to be made on the 4-way connector; then, the bulbs of the sensors
have to be placed in the provided sockets on the boiler body:
-the flow sensor, in the front of the boiler just above the burner;
-the return sensor, in the rear of the boiler on the water distribution pipe.
Possible connections to:
-the circulating pump of the boiler (on the 7-way connector)
-a control thermostat (on the 7-way connector).
See the electrical wiring diagrams in the following pages.
2.3.8.3 OPTIONALS
1. The outside temperature sensor is not delivered with the boiler. Please, order it as an optional
kit (part number xxxxxxxx)
2. For a DHW installation, to connect the DHW temperature sensor and the three-way valve you
have to order a wiring loom as an optional kit (part number xxxxxxxx). Follow the instructions
contained in the kit.
3. The Open Therm device is not delivered with the boiler. You can buy it and connect it to the X6
connector on the ENCON electronic box, placed on the burner.

2.3.8.4 WIRING DIAGRAM – Regency Premix 70
L1N
TITLE
SIZE FSCM No. DWG No.
SCALE DATE SHEET
JOB No.
DRAWN BY
CHECKED BY
MATERIAL
FINISH
TOLERANCES ARE +/-0.5 UNLESS OTHERWISE STATED
PROJECTION
DATE
ITEM DESCRIPTION QTY MATERIAL PART No.
A4
BURNERtech
Combustion Engineers Ltd
Unit 2a, Osman House, Prince Street,
Bolton, BL1 2NP.
Tel: [phone]
Fax: [phone]
MODIFICATIONDATE APPROVED BYREV
D. RICHARDS
N/A
N/A
N/A
N/A 95027
1 OF 1
POWER BURNER
DATE
WIRING DIAGRAM
12111098765432113
54321
GN
RD
BL
YL
BN
OR
GN
PLRD
S3 T1T2B4
PL
RD
BL
BL
54321
BNBKGN
BK
BN
PL
GN GN
5
4
3
2
1
RD
OR
YL
GN
BN BL
PM1A POWER BURNER
ENCON ELECTRONICS
7-WAY
BL = BLUE
BK = BLACK
BN = BROWN
GN = GREEN
GR = GREY
OR = ORANGE
PL = PURPLE
RD = RED
WT = WHITE
WIRE COLOUR KEY:
G. BRIERLEY 3/5/02
1/5/02
3/5/02
LNNPPE
X1
X2
6
X3
X4
X5
X6
T7T8 T6 B5
4-WAY
PLUG
BL
BLPL
GN
COMMON
FLOW
TEMPERATURE
RETURN
TEMPERATURE
CONNECTOR
FOR
SENSORS
OUTSIDE
TEMPERATURE
CONNECTOR
FAN
CONNECTOR
230VAC
EARTH
NEUTRAL
PUMP NEUTRAL
PUMP LIVE
CONTROL
THERMOSTAT
CIRCUIT
230VAC MAX 100VA
GAS VALVE
MODULE FURIMAT 850/50.
GR WT
GR WT
DISPLAY
RS2325
TO FURINT
OPEN
THERM BURNER HEAD
+10
YL = YELLOW
GN
BOILER
BODY
- 18

- 19
2.3.8.5 WIRING DIAGRAM – Regency Premix 100
L1N
TITLE
SIZE FSCM No. DWG No.
SCALE DATE SHEET
JOB No.
DRAWN BY
CHECKED BY
MATERIAL
FINISH
TOLERANCES ARE +/-0.5 UNLESS OTHERWISE STATED
PROJECTION
DATE
ITEM DESCRIPTION QTY MATERIAL PART No.
A4
BURNERtech
Combustion Engineers Ltd
Unit 2a, Osman House, Prince Street,
Bolton, BL1 2NP.
Tel: [phone]
Fax: [phone]
MODIFICATIONDATE APPROVED BYREV
D. RICHARDS
N/A
N/A
N/A
N/A 95028
1 OF 1
POWER BURNER
DATE
WIRING DIAGRAM
12111098765432113
54321
GN
RD
BL
YL
BN
OR
GN
PLRD
S3 T1T2B4
PL
RD
BL
BL
54321
BNBKGN
BK
BN
PL
GN GN
5
4
3
2
1
RD
OR
YL
GN
BN BL
PM1AA POWER BURNER
ENCON ELECTRONICS
7-WAY
BL = BLUE
BK = BLACK
BN = BROWN
GN = GREEN
GR = GREY
OR = ORANGE
PL = PURPLE
RD = RED
WT = WHITE
WIRE COLOUR KEY:
G. BRIERLEY 3/5/02
1/5/02
3/5/02
LNNPPE
X1
X2
6
X3
X4
X5
X6
T7T8 T6 B5
4-WAY
BL
BLPL
GN
COMMON
FLOW
TEMPERATURE
RETURN
TEMPERATURE
CONNECTOR
FOR
SENSORS
OUTSIDE
TEMPERATURE
CONNECTOR
FAN
CONNECTOR
230VAC
EARTH
NEUTRAL
PUMP NEUTRAL
PUMP LIVE
CONTROL
THERMOSTAT
CIRCUIT
230VAC MAX 100VA
GAS
MODULE FURIMAT 850/50.
GR WT
GR WT
DISPLAY
RS2325
TO FURINT
OPEN
THERM BURNER HEAD
+10
YL = YELLOW
L1
N
BN
GN
BL
ST1
ST2
230V FAN
CONNECTOR
VALVE
BL
BN GN
GN
BOILER
BODY

2.4 ADJUSTMENTS
2.4.1 BURNER COMMISSIONING AND STARTING UP
Before attempting to light the burner for the first time, suitably qualified and competent personnel
should inspect the installation to ensure the followings:
a. That all electrical safety circuits are made and the electrical installation has been carried out
according to the instructions in this manual.
b. There must be an adequate ground to the burner and the Live and Neutral should be correctly
connected.
c. The gas supplied is of the type for which the appliance is delivered and factory pre-settled.
Otherwise, see the following section 2.4.2.
d. The gas pipe work is of a suitable size for the burner requirements and the installation has
been checked for leaks and fully purged.
e. The insulating blank placed on the special intermediate section (combustion chamber zone), is
entire and correctly assembled.
f. The condensate drain siphon is filled with water.
THE FOLLOWING OPERATIONS MUST BE CARRIED OUT BY AN MHS AUTHORISED SERVICE
ENGINEER.
Press the On/Off button and after a few seconds the burner should start to pre-purge. Ignition will
commence and the fan will stay at ignition speed for 10 seconds. The burner is pre-programmed
with a step-control so it will not reach maximum fan speed for at least 90 seconds after this.
FIRST check:
manually drive the fan speed back to maximum by pressing the SERVICE button at the same time
as the (“PLUS”) button and holding them down for 3 seconds. Check the CO2levels. These
should be the same as for those shown in the following Table.
Gas Type CO2
G20 – Natural Gas 8,9 – 9,0 %
NOTE: check the flue temperature too. If it is very higher than the value shown in the table of
section 1.4., check and improve the tightness of the insulating blank placed on the special
intermediate section (combustion chamber zone), eventually replacing it.
SECOND check:
drive the fan speed manually to the minimum setting.
This is done by pressing and holding down for 3 seconds the SERVICE button below the STATUS
display at the same time as the (“MINUS”) button.
The STATUS display will now show “L''.
Recheck the CO2levels. These should now be the same as for those shown in the following Table.
Gas Type CO2
G20 – Natural Gas 8,5 – 8,6 %
If adjustments are required to obtain the correct flue gas temperature and CO2 levels, do this
by carrying out the following procedure step by step.
THROTTLE ADJUSTMENT
a. Manually drive the fan speed back to maximum by pressing the SERVICE button as before, but
this time at the same time as the “PLUS” button. Again hold them both down for 3 seconds (the
STATUS display should now show “H”).
b. To increase the CO2 levels at the maximum fan speeds, turn the Throttle screw anti-clockwise
very slowly, checking the levels constantly until the desired level is reached (see next Figure for
position of Throttle adjustment screw).
- 20 -