Cranborne THI 10-50c, THI 5-25c Installation, Commissioning And Servicing Instructions

Cranborne THI 10-50c

Wall Hung Gas Fired Condensing Boiler

Room Sealed or Open Flue

INSTALLATION, COMMISSIONING AND SERVICING

INSTRUCTIONS

IMPORTANT NOTE: THESE INSTRUCTIONS MUST BE READ AND UNDERSTOOD
BEFORE INSTALLING, COMMISSIONING, OPERATING OR SERVICING THIS
APPLIANCE.

THE CRANBORNE THI 10-50c BOILER IS INTENDED FOR USE AS A DOMESTIC /
LIGHT COMMERCIAL APPLIANCE FOR HEATING AND DOMESTIC HOT WATER
INSTALLATIONS.

ND

THIS BOILER IS FOR USE ON GROUP H NATURAL GAS (2
PROPANE GAS (3
REQUIRED WITHIN DOCUMENT IS FOUND RELATING TO SPECIFIC GAS TO BE
FIRED BEFORE FIRING BOILER.

THIS BOILER COMPLIES WITH ALL RELEVANT EUROPEAN DIRECTIVES
EC IDENTIFICATION No. CE-0085AR0323

PUBLICATION NO. 500001115
ISSUE 'B'
AUGUST 2003

rd

FAMILY) I3P. PLEASE ENSURE RELEVANT INFORMATION

FAMILY) I

2H

OR LPG-

HAMWORTHY HEATING LTD CRANBORNE THI 10-50c 500001115/B

i

CONTENTS

I-PRESENTATION ................................................................................................................................... 5

1-DESCRIPTION ...................................................................................................................................... 5

2-RANGE .................................................................................................................................................. 5

II - TECHNICAL SPECIFICATIONS ........................................................................................................... 6

1-CHARACTERISTICS ............................................................................................................................. 6

2-PIPE CONNECTION DIAMETERS........................................................................................................ 7

3-DIMENSIONS ........................................................................................................................................ 7

4-LIST OF COMPONENTS....................................................................................................................... 8

4.1 - Control panel ............................................................................................................................. 9

5-CIRCULATING PUMP CHARACTERISTICS ...................................................................................... 10

6-PRESSURE DROP IN THE BOILER (HEATING CIRCUIT)................................................................ 10

7-THERMAL EFFICIENCY ..................................................................................................................... 10

III - OPERATION ........................................................................................................................................ 12

1-GENERAL OPERATING PRINCIPLE.................................................................................................. 12

2-OPERATION OF THE LMU MANAGEMENT UNIT............................................................................. 13

2.1 - Normal operating conditions ....................................................................................................13

2.2 - Operating diagram ................................................................................................................... 13

2.3 - Principle of air/gas servo-control system ................................................................................. 15

2.4 - Air pressure variation procedure ............................................................................................. 15

2.5 - Emission of pollutants .............................................................................................................. 15

3-FUNCTIONS ........................................................................................................................................ 16

3.1 - Anti-freeze function .................................................................................................................. 16

3.2 - Anti-legionnella function .......................................................................................................... 16

3.3 - Pump run-on after the end of heating ...................................................................................... 16

3.4 - Pump kick or selector valve kick .............................................................................................. 16

3.5 - Boiler overheat protection ........................................................................................................ 16

3.6 - Monitoring of flue gas temperature .......................................................................................... 17

3.7 - Boiler return temperature control ............................................................................................. 17

3.8 - Monitoring of hydraulic pressure ............................................................................................. 17

3.9 - Anti-short burner cycle protection function .............................................................................. 17

3.10 - Cleaning function ..................................................................................................................... 17

3.11 - Regulator shutdown function ................................................................................................... 17

3.12 - LMU programmable key .......................................................................................................... 18

3.13 - Automatic summer/winter switching (only activated with outside sensor) ............................... 18

4-DIFFERENT VERSIONS OF THE THI ................................................................................................ 19

4.1 - THI basic model (without outside sensor, without room sensor) ............................................. 19

4.2 - THI with outside sensor only ...................................................................................................19

4.3 - THI with outside and room sensors ......................................................................................... 22

- 2 -

CONTENT

IV - INSTALLATION ................................................................................................................................... 23

1-GENERAL............................................................................................................................................ 23

2-VENTILATION ..................................................................................................................................... 24

2.1 - THI models with conventional flue connection ........................................................................ 24

2.2 - THI models with balanced flue connection .............................................................................. 24

3-COMBUSTION PRODUCT FLUEING ................................................................................................. 25

3.1 - Conventional flue outlets (B23 model) ..................................................................................... 25

3.2 - Balanced flue outlet ................................................................................................................. 26

4-SUPPORT BRACKET.......................................................................................................................... 32

5-HYDRAULIC CONNECTION ............................................................................................................... 33

5.1 - Recommendations ................................................................................................................... 33

5.2 - Accessories to connect, install or adjust .................................................................................. 33

5.3 - Under-floor recommendations ................................................................................................. 34

5.4 - Heat exchanger flow rate ......................................................................................................... 34

5.5 - Hydraulic connection for models THI 10-50 C ......................................................................... 35

5.6 - Hydraulic connection for models THI 10-50 C + DHW production system of type BS ............ 35

6-GAS CONNECTION ............................................................................................................................ 36

6.1 - Connection of a gas safety solenoid ........................................................................................ 36

7-ELECTRICAL CONNECTION.............................................................................................................. 36

7.1 - Mains connection ..................................................................................................................... 36

7.2 - Connection of the sensors to the LMU management unit ....................................................... 36

7.3 - Under-floor heating safety ....................................................................................................... 36

7.4 - Wiring diagram ........................................................................................................................ 37

V-SETTINGS OF THE INSTALLATION TYPES ..................................................................................... 38

1-SINGLE CIRCUIT ................................................................................................................................ 38

1.1 - Heating pump relay operation ................................................................................................. 39

1.2 - Hydraulically disconnected operation ...................................................................................... 39

2-DOUBLE CIRCUIT............................................................................................................................... 40

2.1 - Heating pump relay operation ................................................................................................. 41

2.2 - Without room sensor ............................................................................................................... 41

2.3 - With room sensor .................................................................................................................... 41

2.4 - Recommended installation of the 2nd circuit and relay clip-ins on the LMU ........................... 42

3-ACCESS THE SETTINGS VIA THE QAA 73 ROOM SENSOR ......................................................... 43

3.1 - Access the lines 51 to 98 ......................................................................................................... 43

3.2 - Access the lines 501 to 755 ..................................................................................................... 44

VI - COMMISSIONING ............................................................................................................................... 45

1-PROTECTION OF THE INSTALLATION............................................................................................. 45

1.1 - Bionibal .................................................................................................................................... 45

1.2 - Bionibagel ................................................................................................................................ 45

2-FILLING THE INSTALLATION WITH WATER .................................................................................... 46

3-PRESSURE SENSOR ......................................................................................................................... 46

4-GAS SUPPLY ...................................................................................................................................... 46

5-SETTING THE MAXIMUM POWER IN HEATING MODE................................................................... 47

6-VERIFICATIONS PRIOR TO COMMISSIONING................................................................................ 47

7-USER INFORMATION......................................................................................................................... 47

8-COMMISSIONING ............................................................................................................................... 48

9-FLAME SETTING ................................................................................................................................ 49

10 - COMBUSTION PRODUCT CHECKING.............................................................................................. 49

- 3 -

CONTENT

VII - GAS CONVERSION ............................................................................................................................ 50

1-SERVICE PRESSURE CONTROL...................................................................................................... 50

2-GAS CONVERSION ............................................................................................................................ 50

2.1 - Conversion from Natural Gas to Propane ............................................................................... 51

2.2 - Conversion from Propane to Natural gas ................................................................................ 51

3-GAS/CO2/CO/NOX FLOW CONTROL................................................................................................ 52

3.1 - Surveillance procedure ............................................................................................................ 52

3.2 - Setting table ............................................................................................................................. 53

VIII - MAINTENANCE .................................................................................................................................. 54

1-SERVICING THE FAN AND THE BURNER........................................................................................ 54

2-SERVICING THE HEAT EXCHANGER OF THE BOILER SHELL...................................................... 55

3-CHECKING ACCESSORIES ............................................................................................................... 55

4-EXPANSION VESSEL PRE-INFLATION PRESSURE CHECK .......................................................... 55

5-COMBUSTION PRODUCT CONDUITS .............................................................................................. 55

6-DRAINING ........................................................................................................................................... 56

7-SENSOR RESISTANCES ................................................................................................................... 56

IX - OPERATING FAULTS ........................................................................................................................ 57

X-OPTIONS ............................................................................................................................................. 59

1-SET-UP TAKING ROOM TEMPERATURE INTO ACCOUNT (REG 73) ............................................ 59

2- CLIP-IN LPB KIT (REG 130)............................................................................................................... 59

3- SECONDARY CIRCUIT CLIP-IN KIT ................................................................................................. 59

4-DOUBLE CIRCUIT KIT (REG 126)...................................................................................................... 60

5-PROGRAMMABLE RELAY CLIP-IN KIT (REG 127)........................................................................... 60

6-CONTROL UNIT ZHTI 46 (REG 129).................................................................................................. 60

7-CONTROL UNIT ZHTI 47 (REG 128).................................................................................................. 61

9-SELECTOR VALVE KIT FOR CONNECTING THI..C/BS ................................................................... 61

XII - NOMENCLATURE .............................................................................................................................. 64

- 4 -

1 - DESCRIPTION

I - PRESENTATION

Standard description: wall mounted condensation

boiler for hot water heating, sealed combustion cir
cuit, pre-mixing burner with air-gas supply, and
linear power modulation connecting combustion
product types B
(04/00)

The THI boiler is pre-set in the factory for natural
gas H (G20) or propane (G31) depending on the
model.

This boiler comprises all the necessary accessories
for the correct working of a water based central hea
ting circuit specifically:

- one boiler comprising:

• a high performance double walled condensa­tion exchanger,

- a pre-mixing burner, with stainless steel refracto­ry grate,

- a variable speed 230 Volt fan controlled by the re­gulator,

- a 230 Volt two way gas valve controlled by the air
pressure,

- electronic regulation which ensures power modu­lation depending on the demands for heating or
DHW (LMU control unit),

- an outside sensor,

- a circulating pump,

- a 3 bar safety-valve,

, C13, C33, following EN 483

23

-

-

OPTIONAL:

- Horizontal flue kit (C13) allowing the boiler to be
connected to a straight horizontal flue.

- Accessories for horizontal connection of the boi­ler (C13) - (extensions, elbows etc.).

- Flue adapter (C33) allowing the boiler to be con­nected to a vertical flue.

- Accessories for vertical connection of the boiler
(C

) - (terminal, extensions, elbows etc.).

33

- Adjustment as a function of the room temperature
(REG 73).

- 2nd heating circuit kit allowing the connection of
a secondary heating circuit (REG 126).

- Clip-in kit secondary circuit allowing the connec­tion of a secondary heating circuit.

- Clip-in communication LPB kit used for cascade
or multi-circuit installations (REG 130).

- Clip-in programmable relay kit allowing a secon­dary pump to work in parallel (REG 127).

- Control unit ZHTi 46 (REG 129) controlling an ad­ditional heating circuit.

- Control unit ZHTi 47 (REG 128) allowing cascade
management for two boilers.

-

- a gas conversion set (to propane from natural gas).

2 - RANGE

Models Functions

THI 10-50 C Only heating

- Domestic hot water production system (type BS).

Combustion products

connection

Chimney conduit (B23)

Horizontal flue (C13)

Vertical flue (C33)

- 5 -

II - TECHNICAL SPECIFICATIONS

1 - CHARACTERISTICS

Model THI 10-50 C

Certification CE0085AR0323

Category / Country of destination: GB II

Nominal power 30/50 °C

Heat rate kW 10,0/50,0

Efficiency on PCI 30/50 °C

Efficiency on PCS 30/50 °C

Efficiency according to 92/42 CEE directive (30%) load % 107,7

Useable gases (NG: Natural gas / PG: Propane) NG H - PG

Combustion product temperature maxi °C

Over-heating safety of combustion products

Flow rate of combustion products mini/maxi

Permitted back pressure (C13) maxi Pa

Air flow required for combustion m3/h 61

NO

x

CO

Heating service pressure

60/80 °CkWkW

60/80 °C%%

60/80 °C%%

°C 85

kg/h 18,0/90,0

mg/kWh

mg/kWh

mini/maxi

bar 1/3

< 60

< 50

2H3P

10,7/52,6

9,7/48,7

107,7/105,1

97,4/95,9

96,9/94,6
87,7/86,3

80

100

Heating circuit water temperature maxi °C 80

Water overheating safety thermostat °C 100

Boiler water capacity liter 3,8

Primary water flow 60/80 °C m3/h 2,1

DP water (at nominal flow) mbar 600

Thermal losses (DT 30 K) W 100

Absorbed electrical power in heating mode:

Control alone

Pump speed 1

Pump speed 2

Pump speed 3

Stand By Position

Power supply/frequency 230 V (+ 10%, - 15%)/50 Hz

Protection factor
models B23
model C13/C

Weight packaged kg 80

33

W

W

W 124

W 147

W

mini : 23

maxi : 53

110

9,2

IP 24
IP 44

- 6 -

2 - PIPE CONNECTION DIAMETERS

Modèles THI 10-50 C

TECHNICAL SPECIFICATIONS

Æ Combustion products B

Æ Combustion products C

23

13

C

33

mm 80/139

mm
mm

80/125

Æ Gas inlet R1

Æ Heating flow/return R1

Æ Condensation outlet mm 25

Æ Safety valve outlet R3/4

Æ DHW production system connection (option § 9 - page 61)

R1

R3/4 with coupling

3 - DIMENSIONS

Fig. 1

102

19

55,5

45,5

117 56 323 ,5

cd

h

i

27

56

b

g

361

Legend:

a : Combustion products outlet
b : Gas inlet
c : Heating flow
d : Heating return
e : /
f : /
g : Condensate drain

h : Safety valve drain
i : DHW production system connection (option)

495

THI-05- 0

Bottom view

120 67,5

a

Rear view

760

- 7 -

765

4 - LIST OF COMPONENTS

Fig. 2

TECHNICAL SPECIFICATIONS

104

13

3

13

11

THI-06-0

12

23

5

14

21

2

7

9

16

15

17

18

1

1) Gas inlet

2) Gas unit (solenoids and regulator) 230 V

3) Gas burner

4) Combustion products outlet

5) Flue gas sensor

6) Heating flow

7) Heating outlet and safety sensor

8) Heating return manifold

9) Boiler return sensor

10)Ignition transformer 230 V

11) Fan 230 V

12)Boiler shell

13) Sight-glass

14) Microprocessor control panel

24

15)3 speed pump 230 V

16) Air bleed

17)Pressure sensor

18) Filter and drain tap

19) Safety valve 3 bar

20) Safety valve outlet

21) Siphon trap

22)Condensate drain

23)Combustion check window

24)DHW production system connection (option)

6 8

19

2022

- 8 -

4.1 - Control panel

Fig. 3

13

1112

10

14

Reset

I

°C

bar

Info

8

O

3

* The function of the heating temperature (2) and DHW temperature (3)

potentiometers differs according the 3 examples below.

**The On/Off switch (after initial lighting) should be maintained in the "ON"

position in order to preserve all the automatic functions of the boiler (an­ti-freeze, anti-legionella functions, etc).

2

j

auto

Function

5

1

9

7

6

4

THI-01-0

TECHNICAL SPECIFICATIONS

1) The "Function" key gives access to 3 operating
modes by simply pressing the key:
auto mode: LED (4) on
winter mode: LED (5) on
summer mode: LED (4) and (5) off

2) Regulation of the heating temperature (setting
read on the display (13)) *

3) Regulation of the DHW temperature (setting
read on the display (13)) *

6) Maintenance key: reserved for servicemen or
maitenance (see overleaf)

7) "Info" key gives access to 5 types of information
on the display (13) by simply pressing the key:
Boiler outlet temperature: LED (9) on
Sensor temperature: LED (9) flashing
Boiler water pressure: LED (8) on
Operating phase: LEDs (8/9) off
Diagnostics: LEDs (8/9) off/

Display (13) flashing

10) Boiler reset button (After each reset, wait for
about 30 seconds before the restart = reset)

11) Alarm: Red LED on

12) Flame indicator: Green LED on

13) Digital display: Alternatively displays the setting
selected by the "Info" key and the current default
code

14) ON/OFF switch (depending on the models) **

THI Without room sensor or outside sensor

The heating (2) and hot water (3) temperatures set­ting are manually set on the boiler control panel.

- The FUNCTION key (1) gives access to 2 opera­ting modes:

• Auto mode operation (4): no access

• Winter mode operation: LED (5) on

• Summer mode operation: LED (5) off

THI Without room sensor and with outside sensor

Possibility of correcting the heating temperature (2)
computed automatically using the outside tempera

­ture and manual setting of the hot water temperatu­re (3) on the boiler control panel. (The room
temperature setting can be changed by + or - 3°C
maximum according to the setting).

- The FUNCTION key (1) gives access to 3 opera-

ting modes:

• Auto mode function:
auto winter = Leds (4) and (5) on
auto summer = Led (4) on + Led (5) off

• Winter mode operation: LED (5) on

• Summer mode operation: LEDs (4) and (5) off

THI With room sensor and outside sensor

Fitting the QAA73 room sensor cancels the func­tions of the heating temperature setting (2) and hot
water setting (3) on the boiler control panel. All the
temperatures required, together with the heating
programmes, are set on the QAA 73 (refer to the
sensor instructions).

- 9 -

5 - CIRCULATING PUMP CHARACTERISTICS

TECHNICAL SPECIFICATIONS

The boiler’s integrated circulating pump is equipped
with a 3 speed motor (refer to section

1 - page 6).

Fig. 4

Electrical consumption of the heating circulating
pump can be optimised by adapting its speed to the
needs of the installation.

6 - PRESSURE DROP IN THE BOILER (HEATING CIRCUIT)

Fig. 5

7
6
5
4
3
2
1

Pressure drop (mWG)

0

0 500 1000 1500 2000

3

Flow rate (dm

/h)

UPS 25-80-180

7 - THERMAL EFFICIENCY

Fig. 6

1,10

1,08

1,06

1,04

1,02
1,00

0,98

PCI efficiency

0,96

0,94

0,92

0,90

10

Maximum rate

20 30 40

Installation- empératurereturn t

- 10 -

Minimum rate

50

T50-03- 3

60 70

III - OPERATION

1 - GENERAL OPERATING PRINCIPLE

The THI boiler is a very high efficiency condensation
boiler owing to the burner and heat exchanger that
benefit from our longstanding experience.

The over-sized fin tube exchanger and its combus­tion chamber cooled by water in the upper section,
combines the functions of heat exchanger and con
denser.

Second generation digital control continuously opti­mizes the operating rate by using information sent to
the microprocessor by the sensors fitted on the boi
ler:

- boiler flow sensor,

- boiler return sensor,

- outside temperature sensor,

- flue gas flue gastemperature sensor,

- room sensor,

- pressure sensor,

- fan speed control (pneumatic air/gas control),

- communication bus with external regulators.

-

-

Each of the sensors is allocated to an algorithm that
optimizes the operation and generates information
or fault codes that can be read from the display of
the control panel or QAA73 room sensor.

- 12 -

2 - OPERATION OF THE LMU MANAGEMENT UNIT

2.1 - Normal operating conditions

OPERATION

To access the operating phases of the LMU (display
level A4), press the info key (7) three times. The dif

-

Fig. 7

ferent phases will then be displayed (13).

Note:

INFO-0

- The phase display will stop automatically after 8
minutes,

- Otherwise, press the info key 2 times more.

Programming order for normal operating conditions

Display Meaning Display Meaning

Stand-by (no heating request) Ignition - safety time

Start-up blocked Heating mode operation

Fan speed rise time Hot water mode operation

Pre-ventilation time Heating + DHW operation (disabled for

THI)

Waiting time Post-ventilation with last operation

command

Pre-ignition time Return to initial setting

Fault position (display of current fault
code)

°C

bar

Reset

Info

713

2.2 - Operating diagram

Fig. 8

HMI
display:

Phase

Head
demand

Flame

Ignition
BV

LP (2)

LP (3)

LP (4)

NoG_Max
N_Vor

-N_Vor_Delta

+N_VL_Delta

N_VL

+N_ZL_Delta

N_ZL

-N_ZL_Delta

N_TL

-N_TL_Delta

NoG_Null

THI-65-3

7494f01D/0801

Home return

TNB

PH_TNB

Logic on

Logic off

On deviation
transition to home run

TLO

PH_TLO PH_TNN

022 1 2 3 654

Standby

TNN

PH_
STANDBY

PH_
STARTVER

PH_
STANDBY

tv TBRE

THL1

PH_
THL1_1

PH_TV PH_TB RE PH _TW1 PH_TW2 PH_TVZ

Depend on
para meter
setting

TW1 TW2

Deviati on leads to lockout

On deviation transition to
specified or following phase

10 H

11 DHW

12 H+DHW

tsa

Operation

tvz

tsa1 tsa2

PH_
TSA1_1

PH_
THL2

Z Z

Z ZZ Z Z Z

Depend on
parameter
setting

PH_
TSA2_1 PH_TI

Z

PH_

THL2

Z

Z Z

THL2

THL2

ti

PH_

PH_

20 2 4 7 21 99

tn

PH_
MODU­LATION

PH_
THL2

PH_
THL2

PH_
THL2_1 PH_TN_1

Depend on
parameter
settin g

THL1 (TW1)

PH_

PH_TW1

THL1_2

Depend on
parameter
settin g

Permitted range

Prohibited range

-> Home run

Prohibited range

-> Lockout

tsa

tsa1 tsa2

PH_
TSA1_2

Z Z

PH_
THL2

Z

Depend on
parameter
setting

Z

THL2

PH_

PH_

TSA2_2

THL2_2 PH_TN_2

PH_
THL2

PH_

TSA1_2

Z

Z

Depend on
para meter
setting

Control signal
Ideal signal

Transition criterio n

Triggering forced prepurging

tn

PH_
STOER

Z

Z

Z

- 13 -

Explanation of the operating phases

Display Phase Description

Shut down

PH_STANDBY (unlimited) The boiler is on standby and waiting for a heating request.

OPERATION

PH_STARTVER Start-up is blocked. The corresponding diagnostic code is emitted (shunt

Start-up: heating request

PH_THL1_1 (THL1) Fan speed rise time:

PH_TV (tv) Pre-ventilation time

PH_TBRE + PH_TW1 Tapering time

PH_TVZ (tvz) Pre-ignition time:

PH_TSA1_1 + PH_TSA2_1 (tsa) Safety time

and

PH_TI + PH_MODULATION: Burner operation

and

X10-03).

- This time ends as soon as the fan motor speed reaches the program
for pre-ventilation

- This time ends as soon as the ignition load programmed for pre-venti­lation is reached

- Appearance of the ignition arc prior to opening the gas valve, which oc­curs at the start of phase 6

- A flame signal should be present before the safety time has elapsed. If
this does not occur, another ignition attempt is made.

10: heating operation
11: domestic hot water operation
12: heating and domestic hot water operation (disabled for THI)

and

• PH_TI...............................:

• PH_MODULATION...........:

Flame stabilisation interval.

In this phase, the LMU (regulator) send its results.

Return to standby: The switch from the operating position to the Standby position is split into “shut-down”

and “return to initial setting”

Shut-down: This occurs when the heating request disappears

PH_THL2_1 + PH_TN1 Post-ventilation time

and

- The fan remains on during the post-ventilation time

Return to initial setting: Compulsory switch from the shut-down position to standby. This phase is also

used to bring the boiler to standby position after exceptional events such as a RESET.

PH_TNB + PH_TLO + PH_ TNN:

Return to initial setting

- 14 -

2.3 - Principle of air/gas servo-control system

The gas valve fitted on each boiler is controlled by
the air pressure supplied by the fan, thus guaran

­teeing a correct air-gas ratio over the whole modu­lation range (constant CO2). This ratio remains
constant despite any pressure drop in the combus

­tion products outlet or the air intake. The air-gas link
is pneumatic.

Fig. 9

Operating characteristics of the air/gas servo-system

P2: gaz pressure at valve regulator outlet
PL: servo-system air pressure

P2 mbar GN

7
6
5
4
3
2
1
0

01234567PL mbar

OPERATION

2.4 - Air pressure variation procedure

Linear pressure modulation is carried out by a 230 V
variable-speed fan controlled by the LMU which cal
culates the speed needed at any given time to pro­duce the required pressure.

2.5 - Emission of pollutants

This air/gas control combined with high efficiency
pre-mixing burner enables CO and nitrogen oxide
(NOx) emissions to be obtained that lie within the
values laid down by the most demanding of quality
standards.

-

- 15 -

3 - FUNCTIONS

OPERATION

3.1 - Anti-freeze function

- Boiler anti-freeze protection: When the boiler

temperature is below 5°C, the burner and the
heating circuit pump are switched on. When the
temperature increases and exceeds 15°C, the
burner stops and the pump continues to circulate
for 10 minutes.

- Anti-freeze protection for the installation: This

function uses the real outside temperature. It
adopts a different behaviour depending on the
temperature. If no measured outside temperature
is available, the function is blocked.

Different reactions can occur depending on the
outdoor temperature measured:

• If the outdoor temperature is less than or equal
to -5°C, the pumps operate continuously,

• If the temperature lies between -4 and 1.5°C,
the pumps operate for 10 minutes every 6
hours.

• If the outdoor temperature is over 1.5°C, the
pumps shut-down (no heating request).

Any domestic hot water request is given priority.

- Building anti-freeze protection:

The anti-freeze function of the building is a control
function (available with the QAA73 room sensor)
used to maintain the room temperature at a mini
mum value, thus preventing the risk of freezing in
the building.

3.2 - Anti-legionnella function

To provide a substantial degree of protection
against the development of pathogenic bacteria in
the domestic hot water tank during prolonged shut­downs, the domestic hot water must be heated once
a week to a temperature above 60°C.

-

3.3 - Pump run-on after the end of heating

When the heating mode ends, the heating circuit
pump remains on for a certain period (depending on
the settings used : QAA

In hot water storage systems, when domestic hot
water heating ends, the heating circuit pump re
mains on until the boiler temperature drops below
70°C. During this pump run-on period, the selector
valve remains in the “domestic hot water feed” posi
tion.

3.4 - Pump kick or selector valve kick

If the heating circuit pump has not operated or if the
selector valve has not been activated for more than
about 24 hours, these elements are activated during
operating stops for approximately 5 seconds.

3.5 - Boiler overheat protection

The boiler flow sensor in combination with the hea­ting return sensor provide the overheat safety func­tion.

There are two safety levels:

- if the first temperature value is exceeded, this is
signalled by a fault code on the display screen,

• THI 10-50 : 90°C

- if the second temperature value is exceeded
(100°C), it is signalled by an alarm code on the
display. The boiler switches to safety mode. The
boiler must be reset to be restarted.

If the temperature is exceeded, the heat present
must be evacuated through the fan and circulation
pump.

The two elements (fan and circulation pump) remain
on until the boiler shell temperature drops.

73 setting : 544).

-

-

The anti-legionnella function is used for this purpo­se. It heats the hot water storage tank once a week,
on Monday, after the first load, to a 65°C “anti-le
gionnella” temperature.

-

- 16 -

In the control algorithm, supervision of the tempera­ture difference DT between the flow and return re­sults in the shutdown of the burner if DT is above
56°C.

OPERATION

3.6 - Monitoring of flue gas temperature

The monitoring of flue gas temperature is not
classed as a function related to safety, but is a prio

-

rity factor in the control of the boiler.

- The boiler operates at minimum power if the flue
gas temperature exceeds 85°C,

- The boiler is on "Stand-by" if the flue gas tempe­rature reaches 88°C.

The boiler can only be restarted automatically after
15 minutes if there is no longer a fault.

3.7 - Boiler return temperature control

The information from the return sensor is used in the
event of a very low flow (large

DT) (reduction in bur-

ner power or shut-down of the burner).

It is also enabled for cascade connection.

3.8 - Monitoring of hydraulic pressure

This is a priority function with respect to the control
of the boiler.

- the power of the boiler is limited if the pressure is
above 4 bar,

- the boiler reduces power to 20% if the pressure in
between 0.2 and 0.4 bars (fault code is dis

-

played),

- the boiler sets of an alarm and the pump stops if
the pressure is lower than 0.2 bars (alarm code is
displayed).

The boiler must be reset to clear the fault position if
the minimum value has been exceeded.

3.10 - Cleaning function

Fig. 10

Reset

11

°C

Info

13

RAMO-SF

bar

j

6

To enable this function, press the clean key (6) until
the red LED (11) lights up then release it. The LED
(11) then starts flashing once per period. The signal
ling coded “SF” is displayed on the screen (13).

Heating takes place at maximum calorific power un­til arriving at the maximum temperature TKSmax.

To disable the cleaning function, press on the clean
key (6) for 3 seconds then release it.

3.11 - Regulator shutdown function

The regulator shut-down function enables the fan
motor speed to be set manually via a domestic hot
water temperature potentiometer (3), and therefore
the heat output of the boiler.

Fig. 11

Reset

Reset

11

11

13

13

°C

°C

bar

bar

Info

Info

-

3.9 - Anti-short burner cycle protection
function

To prevent the boiler from cutting out suddenly, the
power failure differential is adjusted according to the
real temperature curve of the boiler.

j

j

RAMO-AR

RAMO-AR

- Press the clean key (6) for longer than 8 seconds,

• The red LED (11) flashes twice per period.

• The codes appear on the display
(13) and flash twice. This code corresponds to
the percentage of the boiler heating rate.

The safety function and the “all or nothing” regulator
are operating.

To disable the regulator shutdown function, press
the clean key (6) for 3 seconds then release it.

- 17 -

6

6

OPERATION

3.12 - LMU programmable key

The following functions can be allocated to the pro­grammable key via the setting
KonfigEingang (QAA 73 setting : 614):

- 0: The programmable key function is not used.

- 1: Default, modem function enabled, if the contact
(X10-04) is closed; disabled if the contact is
open.

- 2: Modem function disabled, if the contact (X10-

04) is open; enabled if the contact is closed.

- 3: Hot air curtain function enabled, if the contact
(X10-04) is closed.

Hot air curtain function (swimming pool):

This function enables the boiler setting to be raised
to its maximum value.

It can be enabled in summer and winter modes.

- Modulation of the burner output is maintained.

- Domestic hot water priority is maintained.

- This function is enabled when the contact is

closed.

Modem function:

The modem function allows the boiler to be placed
on "standby" or to be switched off via the telephone.
All protection functions (e.g. anti-freeze function,
pump kick) remain active.

3.13 - Automatic summer/winter switching
(only activated with outside sensor)

The automatic summer/winter switching function
enables summer mode to be switched to winter
mode (and vice versa) throughout the year without
the need for any intervention.

The heating is shut down (when switching from win­ter mode to summer mode) when the average outsi­de temperature measured over the preceding 24
hours is over the +1°C setting, namely 20°C.

The heating is also started up again (when switching
from summer mode to winter mode) automatically
when the average outside temperature measured
over the preceding 24 hours is below the -1°C set
ting, namely 18°C.

-Note:
The switchover setting is set to 19°C and can only

be changed by using the QAA 73 room sensor.
The automatic mode must obviously be activated

on the boiler as well as on the QAA 73 room sen
sor for the automatic summer/winter switching to
be available.

This function is activated by default in the QAA 73
basic configuration.

-

-

On the other hand, when this function is activated,
some of the other functions are not ensured:

- The antifreeze function of the installation is not
guaranteed.

- The anti-legionella function of the unit is no longer
used.

- 18 -

4 - DIFFERENT VERSIONS OF THE THI

,

,

,

OPERATION

The standard configuration is for the
connection of:

!

- one radiator circuit (CC1),

- one under-floor heating circuit
(CC2) via the 2

nd

circuit clip-in kit.

Fig. 12

auto

Function

23

4

THI-66-0

15

4.1 - THI basic model (without outside
sensor, without room sensor)

The heating and domestic hot water flow temperatu­res are set manually with the respective potentiome­ters (2 and 3) on the boiler control panel.

The regulator (LMU management unit) thus sets the
heating rate required to provide the heating and hot
water settings specified by the user.

The “Function” key (1) switches between the sum­mer (hot water only) and winter (heating and hot wa­ter) modes. (The auto function is not accessible in
this case).

Please refer to section 4.1 - page 9 - Chapter II ­TECHNICAL SPECIFICATIONS.

Note: The installation of under-floor heating is not

possible in this configuration.

4.2 - THI with outside sensor only

4.2.1 - Principle

The domestic hot water temperature is set manually
using the potentiometer (3) on the boiler control pa
nel

Refer to section 4.1 - page 9 - Chapter II - TECHNI­CAL SPECIFICATIONS.

Note:

- An under-floor heating system can be connected
by following the instructions in section

4.2.3 -

page 19.

4.2.2 - Modification of the room temperature

The room temperature setting is pre-set to 20°C on
the LMU management unit, it can be modified if re

-

quired:

- Set the heating temperature potentiometer (2) to
the required value,

- The display indicates the correction made by +/­3°C with respect to the 20°C value,

The correction is recognised by the LMU by lea­ving the potentiometer on the required position.

4.2.3 - Modification of the heating curve slope

The heating curve slope depends on the characte­ristics of the building and the size of the heating ins­tallation.

Fig. 13

100

90
80
70
60
50
40
30

Boiler setpoint

temperature (°C)

20
10

0

20 15 10 5 0 -5 -10 -15 -20

Outside temperature (°C)

2,4

2
1,8
1,6
1

4

2

1
1

Slope

0,8
0,6

4

0

0,2

The slope of the heating curve is pre-set in the fac­tory to the value 15 for a radiator system and theo­retically gives an room temperature of 20°C for a
standard installation.

Note: The maximum permitted flow temperature is

limited by TKSmax (line 504, via the QAA73

-

room sensor)

The heating flow temperature is calculated automa­tically by the regulator (LMU management unit), and
determined according to the outside temperature
and the slope of the heating curve. The room tem

­perature can be modified by only + or - 3°C using the
heating temperature potentiometer (2).

The “Function” key (1) switches between the sum­mer (hot water only) and winter (heating and hot wa­ter) modes.

- 19 -

OPERATION

The characteristics of the living area (heating surfa­ce, insulation) may require the pre-set values on the
LMU to be adjusted.

- For a radiator heating system:

• Reset the room temperature by +/-3°C (section

4.2.2 - page 19) then if this correction is not
sufficient,

- For an under-floor heating system:

• Reset the value of the heating curve slope of
15 (factory setting) to 8 (section

20) and according to the installation require­ments,

• Modify the room temperature by +/-3°C (sec­tion 4.2.2 - page 19).

• Modify the heating curve slope (section 4.2.3.1

- page 20).

4.2.3.1 - Procedure for modifying the parameters of the heating curve slope

Initial display: Green LED “°C” is on

1

The display shows the heating flow temperature.

Press the key until is displayed then release it and press for the same period until is

Info

2

displayed (the display indicates then : intermediate positions).

3

After a few moments, is displayed.

°C

bar

Info

INFO-22

4.2.3.1 - page

4

Press on the key twice until is displayed on the screen.

5

6

7

setting of the slope permutes with the default value of the slope.

Only when the display shows press the key until the “bar” LED flashes:

Increase the value by pressing until the value is displayed.

Store the value by pressing the key for a certain time until the LEDS “°C” and “bar”

Info

Info

Info

Info

8

°C

bar

Info

extinguish

INFO-8

9 Return to the initial display

°C

bar

Info

INFO-15c

- 20 -

4.2.3.2 - Procedure for modifying the parameters of the parallel shift of the heating curve

OPERATION

Initial display: Green LED “°C” is on

1

°C

bar

Info

INFO-22

The display shows the heating flow temperature.

Press the key until is displayed then release it and press for the same period until is

Info

2

displayed (the display indicates then : intermediary positions)

3

After a few moments, is displayed.

4

Press on the key three times until is displayed on the screen.

5

6

7

setting of the parallel shift permutes with the default value of the shift.

Only when the display shows press the key until the “bar” LED flashes:

Increase the value by pressing until the value is displayed.

Info

Info

°C

bar

Info

Info

INFO-15c

Store the value by pressing the key for a certain time until the LEDS “°C” and “bar”

Info

8

°C

bar

Info

extinguish

INFO-8

9 Return to the initial display

4.2.3.3 - Return to the initial display

Procedure Observation

Press the key until the display appears

then release the key.

Info

This enables you to return to the initial position (i.e. the
display shows the heating flow temperature) when the
procedures

4.2.3.1 - page 20 and 4.2.3.2 - page 21 are
being applied or during any other actions on the boiler
control panel.

- 21 -