Ferroli TEMPRA 24 Manual

Appr. nr. B99.04 A - CE 0461 BL 0520
TEMPRA 24
copper wall-mounted system,
gas fired boiler for central heating,
fan assisted, room sealed compartment,
electronic flame ignition and control
INSTALLATION, SERVICE AND USER INSTRUCTIONS
cod. 3543805/3 - 10/2004
G C N° 41-267-13

2
Tempra 24
CE MARK
CE mark documents that the Ferroli gas appliances comply with the requirement contained in European
directives applicable to them.
In particular, the appliances comply with the following CEE directives and the technical specifications
provided from them:
• Gas appliances directive 90/396
• Efficiencies directive 92/42
• Low tension directive 73/23 (modified from the 93/68)
• Electromagnetic compatibility directive 89/396 (modified from the 93/68)
IMPORTANT
Your "benchmark" Installation, Commissioning and Service Record Log Book will be enclosed in
your customer information pack.
"This record must be completed and left with the end user"
"All CORGI Registered Installers carry a CORGI ID card and have a registration number. Both
should be recorded in your central heating log book. You can check with the CORGI register by
calling CORGI on 01256 372300".
Ferroli is a member of the Benchmark initiative and fully supports the aims of the programme. Benchmark
has been introduced to improve the standards of installation and commissioning of central heating
systems in the UK and to encourage the regular servicing of all central heating systems to ensure safety
and efficiency. Please see installation and servicing guidelines.
INDEX
1. DESCRIPTION....................................................................................................................................................... 3
2. TECHNICAL AND DIMENSIONAL CHARACTERISTICS......................................................................................4
3. INSTALLATION DETAILS ..................................................................................................................................... 9
4. COMMISSIONING AND TESTING..................................................................................................................... 28
5. ADJUSTMENT AND GAS CONVERSION .......................................................................................................... 29
6. MAINTENANCE AND CLEANING .................................................................................................................... 31
7. REPLACEMENT OF PARTS ................................................................................................................................ 33
8. FAULT FINDING ................................................................................................................................................. 37
9. ELECTRICAL AND FUNCTIONAL SCHEME ...................................................................................................... 39
10. USER INSTRUCTIONS ...................................................................................................................................... 41

3
Tempra 24
1. DESCRIPTION
1.01 Introduction
The Tempra 24 is defined as a “room sealed” boiler, all air required for combustion is taken from outside the
room in which it is installed. It is a new high performance gas fired heat generator for central heating. A special
feature of this boiler is its built-in electronic flame ignition and control unit making burner operation completely
automatic and safe. The main components are as follows:
• Copper heat exchanger consisting of four finned tubes specifically shaped for high efficiency.
• Ceramic fibre insulated combustion chamber
• 12 stainless steel bladed burners specifically designed for this boiler.
• Fan for discharge of combustion products and intake of combustion air.
• Differential air pressure switch. For safety reasons, this ensures the burner ignites only when the fan
is functioning correctly.
• Hermetically sealed compartment made from corrosion-resistant steel enclosing the above components.
• Combination gas safety valve with modulator, complete with pressure stabiliser.
• Pressure relief valve for the central heating circuit set to open at 3 bar.
• Built-in Expansion vessel.
• Variable speed pump.
• Central heating flow temperature adjustment thermostat.
• Central heating limit thermostat.
• Overheat safety thermostat.
• Electronic control unit for automatic flame ignition and control.
• Central heating flow temperature sensor.
1.02 Instructions and regulations
Assembly, installation, first start up and maintenance must be carried out by competent persons only, in accordance
with all current technical regulations and directives.
c.o.s.h.h.
Materials used in the manufacture of this appliance are non hazardous and no special precautions are
required when servicing.
3Related Documents
Related documents
This appliance must be installed strictly in accordance with these instructions.
The Gas Safety Regulations (Installations & Use).
The Local Building Regulations.
The Building Regulations.
The Buildings Standards (Scotland - Consolidated) Regulations.
British Standards Codes of Practice:
B.S. 7593 TREATMENT OF WATER IN DOMESTIC HOT WATER CENTRAL HEATING SYSTEMS
B.S. 5546 INSTALLATION OF HOT WATER SUPPLIES FOR DOMESTIC PURPOSES
B.S. 5440 Part 1 FLUES
B.S. 5440 Part 2 AIR SUPPLY
B.S. 5449 FORCED CIRCULATION HOT WATER SYSTEMS
B.S. 6798 INSTALLATION OF GAS FIRED HOT WATER BOILERS
B.S. 6891 GAS INSTALLATIONS
B.S. 7671 IEE WIRING REGULATIONS
B.S. 4814 SPECIFICATION FOR EXPANSION VESSELS
B.S. 5482 INSTALLATION OF LPG
Model Water Bye Laws
For Northern Ireland the rules in force apply

4
Tempra 24
Fig. 1
2. TECHNICAL AND DIMENSIONAL CHARACTERISTICS
2.01 Technical information
Tempra 24 boilers are central heating generators and are produced as standard to function with natural gas
or Liquid Petrolium Gas converted appliances.
98
15536 155
460
100 25 150
272
25 160
9836 155 114
760
706
965
175
190
155
70 120 120 150
110
Ø80Ø80 Ø80
114
3
2
1
Key
1. Central Heating flow
2. Gas supply
3. Central Heating return

5
Tempra 24
N.B. - The gas pressures at the burner and gas flows during the central heating phase given in the table refer
to nominal boiler output. To reduce this output (where necessary), gas pressure must be reduced until the
required output level is reached (see figures 4 and 5).
• Maximum working temperature for central heating flow: 85°C
Technical Data
Gas supply
Pmax Pmin
Nominal Heat Input (Net)
Nominal Heat Output
Output
Pmax Pmin
kW 23,3 9,7
kW 25,8 11,2
Dimensions, weights, fittings
Depth mm 272
Width mm 460
Height mm 760
Hot water capacity litres 1,5
Expansion vessel pre-fill pressure bar 1
Expansion vessel capacity litres 8
Minimum central heating operating pressure bar 0,8
Maximum central heating operating pressure bar 3
Maximum central heating operating temperature °C90
Index of protection IP 44
Power supply
Power supply voltage/frequency V/Hz 230/50
Max Power Absorbed W 125
C.H. return (with isolation valve fitted) mm 22
C.H. flow (with isolation valve fitted) mm 22
Gas system fittings (with isolation valve fitted) mm 22
Weight with packaging kg 35
Central heating
Natural gas rate (G20) nm3/h 2,73 1,19
Main injectors, Natural Gas (G20) mm 12 x 1.3
Burner pressure, Natural Gas (G20) mbar 11,8 2,5
Supply pressure, Natural Gas (G20) mbar 20,0
LPG gas rate (G31) kg/h 2,00 0,87
Main injectors, LPG (G31) mm 12 x 0.77
Burner pressure, LPG (G31) mbar 36,0 7,0
Supply pressure, LPG (G31) mbar 36,0
Safety valve bar 3

6
Tempra 24
2.03 Boiler water flow diagram
Fig. 3
2.02 Boiler main components
Fig. 2
+
-
43
49 50
56
81
44
32
20
82
5
29-187
16
10 7 11
14
34
Key
5 Room sealed compartment
7 Gas inlet
10 Central heating flow
11 Central heating return
14 Safety valve
16 Fan
19 Combustion chamber
20 Burner assembly
21 Main injector
22 Burner
26 Combustion chamber insulation
27 Copper heat exchanger
28 Flue collector from heat exchanger
29 Internal flue exit
32 Central heating pump
34 Central heating flow temperature sensor
36 Automatic air vent valve
43 Air pressure switch
44 Gas valve
49 Safety overheat thermostat
50 Central heating flow limit thermostat
56 Expansion vessel
62 Time clock (option)
63 Central heating temperature adjustment
81 Ignition electrode
82 Sensor electrode
84 Primary gas valve solenoid
85 Secondary gas valve solenoid
98 On/Off/Reset switch
145 Central heating pressure gauge
187 Flue restrictor
RESET
OFF
ON
0
5
1
234
6
bar
98 63 145
1174485841410
34
20
21
22 82 81
49
28
5
29 187 43
56
16
27
50
19
26
36
32
62
°C

7
Tempra 24
2.04 Central heating adjustment (not normally required)
To adjust boiler heat input (thus also regulating heat output to the central heating water) simply adjust the main
burner via the electronic control board (fig. 4 and see paragraph 5.04).
The diagrams indicate the variation in heat output to the water as burner working pressure is varied.
Adjusting boiler output to the actual requirements of the central heating system will minimise boiler
cycling thus saving fuel, varying the output has virtually no effect on the efficiency and combustion
characteristics of the boiler.
Diagram of pressures and outputs with Natural gas
and with LPG (Propane)
Fig. 4
kW
kcal/h
X 1000
m
b
ar
18 19 20 21 22 23
5
10
15
20
25
30
35
9 1011121314151617
91011121314 18192015 16 178
G31
G20

8
Tempra 24
Fig. 6
Pressure loss diagram
SIZING OF ADDITIONAL EXPANSION VESSELS:
Deduct from the value given in the table the 8 litre
vessel supplied.
Note:
1. Fill C.H. installation to min. 1.5 bar.
2. Expansion vessel must be fitted to central
heating return pipe.
3. The standard 7 litre expansion vessel is
charged to 1 bar.
4. The additional expansion vessel should be
charged to 1 bar.
SAFETY VALVE
SETTING (bar)
VESSEL CHARGE
PRESSURE (bar)
INITIAL SYSTEM
PRESSURE (bar)
TOTAL WATER
CONTENT of SYSTEM
3.0
0.5 1.0 1.5
1.0 1.5 2.0 1.5 2.0 2.0
EXPANSION VESSEL VOLUME (litres)
LITRES
25 3.5 6.5 13.7 4.7 10.3 8.3
50 7.0 12.9 27.5 9.5 20.6 16.5
75 10.5 19.4 41.3 14.2 30.9 24.8
100 14.0 25.9 55.1 19.0 41.2 33.1
125 17.5 32.4 68.9 23.7 51.5 41.3
150 21.0 38.8 82.6 28.5 61.8 49.6
175 24.5 45.3 96.4 33.2 72.1 57.9
200 28.0 51.8 110.2 38.0 82.4 66.2
0.140 0.259 0.551 0.190 0.412 0.33
For syst. volumes other than
those given above, mult. the syst.
volume by the factor across
m |h
3
Q
8
7
6
5
4
3
2
1
00.5 1.5 2.512
Hmbar x 100
2.05 Pump characteristics
The pump head available for circulating the water is given
in fig. 5.
N.B. - The pump is factory set at position 3. The pump is a
Grundfos type 15-50 UPS series.
Grundfos Pump per formance graph
Note - Minimum flow through boiler heat exchanger at any
time should not fall below 6 litres per minute.
If the total volume of water in the system exceeds 40 litres
an additional expansion vessel must be fitted to the central
heating return pipe.
Fig. 5
1 2 3 Speed settings
ABoilers pressure drop
BAvailable pump head C.H.

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Tempra 24
3. INSTALLATION DETAILS
Gas Safety (Installation & Use) Regulations
In the interest of safety, it is the law that all gas appliances are installed by a competent person in accordance
with the above Regulations, Building Regulations/Building Standards Scotland, Codes of Practice, current I.E.E.
Regulations and the byelaws of the Local Water Undertaking. Failure to comply with the Regulations may lead to
prosecution; it is your responsibility to ensure that the law is complied with.
N.B. For Northern Ireland the rules in force apply.
Important - If the boiler is to be fitted in a timber framed building it should be fitted in accordance with the Institute
of Gas Engineers document IGE/UP/7. If in doubt advice should be sought from the Local Supplier.
Location of Boiler
The installation of the Tempra 24 must be on a suitable non-combustible load bearing wall which will provide
an adequate fixing for the boiler mounting bracket assembly. The location should be in an area where
the water pipes will not be subjected to frost conditions. In siting the combination boiler the following
limitations must be observed:
The boiler may be installed in any room or internal space, although particular attention is drawn to the
requirements of the current I.E.E. wiring regulations and in Scotland the electrical provisions of the building
regulations applicable in Scotland, with respect to the installation of the combination boiler in a room or
internal space containing a bath or shower.
Where a room sealed appliance is installed in a room containing a bath or shower any electrical switch
or appliance control utilising mains electricity must be situated so that it cannot be touched by a person
using the bath or shower.
Air Supply
The room or compartment in which the boiler is installed does not require a purpose provided vent when
using the standard concentric flue.
Flue System
The boiler allows the flue outlet to be taken from the rear of the boiler, from either side or vertically.
A standard flue length of 0.75 metres is provided. Alternative lengths of two or three metres can be supplied
(equivalent to wall thicknesses of up to 565, 1815 and 2815mm for rear flues, deduct 91mm plus distance from
side wall for side outlet flues). It is absolutely essential, to ensure that products of combustion discharging from
the terminal cannot re-enter the building, or enter any adjacent building, through ventilations, windows,
doors, natural air infiltration or forced ventilation/air conditioning.
Gas Supply
If necessary the local Gas supplier should be consulted, at the installation planning stage, in order to establish
the availability of an adequate supply of gas.
An existing service pipe must not be used without prior consultation with the Local Gas supplier.
A gas meter can only be connected by the Local Gas supplier, or by a Local Gas suppliers Contractor.
Installation pipes should be fitted in accordance with BS6891-1988.
Appliance inlet working pressure must be 20mbar MINIMUM, for NG and 37 mbar minimum for LPG.
Pipework from the meter to the combination boiler must be of an adequate size.
The boiler requires 2.73m3/h of natural gas, and 2,00 kg/h of LPG.
Do not use pipes of a smaller size than the boiler inlet gas connection.
The complete installation must be tested for gas soundness and purged as described in BS6981-1988. All
pipework must be adequately supported. An isolating gas valve is provided and should be fitted on the boiler gas
inlet. Please wait 10 minutes when lighting from cold before checking gas rate. Gas pressures should be checked
after the boiler has operated for 10 minutes to reach thermal equilibrium.

10
Tempra 24
NOTE: A by-pass that will ensure a minimum flow rate
of 6 l/min. at all all time must be fitted as far as possible
from the boiler if thermostatic radiator valves are fitted
thoughout.
Fig. 7
Central Heating
Detailed recommendations are given in BS6798, BS5449, BS6700 and CP342 Part 2. Pipework not forming part of
the useful heating surface should be insulated to prevent any heat losses or possible freezing (i.e. in roof spaces
or ventilated underfloor spaces). Drain taps should be positioned at the lowest point of the system in accessible
locations to permit the whole system to be drained down. The drain taps should be in accordance with
BS2879. Copper tubing to BS2871, Part 1 is recommended for water carrying pipework. Pipework in
horizontal runs should have a gradient where possible to facilitate the removal of air. Ensure that the
boiler heat exchanger is not a natural point for air collection. A typical heating system with domestic
hot water circuit is illustrated in fig. 7.
Important - If thermostatic radiator vales are fitted a automatic bypass must be fitted to ensure a minimum flow
rate through the boiler of 6 l/min. The bypass should be fitted as far as possible from the boiler.
Make Up Water
Provision must be made for replacing water lost from the sealed system. Reference should be made to
BS6798, for methods of filling and making up sealed systems. There must be no direct connection between
the boiler's central heating system and the mains water supply. The use of mains water to charge and
pressurise the system directly, is conditional upon the Local Water Byelaws. Again any such connection
must be disconnected after use.
Attention - is drawn to the Model Water Byelaws.
Fittings manufactured from duplex (alpha-beta) brass are not acceptable for underground use and certain water
undertakings will not accept their use above ground.
Ensure all pipework is adequately supported
Gas
Additional expansion vessel C.H.
(if required)
By-pass
AUTOMATIC BY-PASS
The by-pass must be capable of
passing 6 l/min of water when
all the trv’s are shut down