Riello RTT Series User guide

cod. Doc-0079323 rev. 1 03/2016
RT T 378-930
EN INSTRUCTIONS FOR THE INSTALLER AND FOR THE TECHNICAL ASSISTANCE CENTRE

2
RANGE
MODEL CODE
RTT 378 20093090
RTT 448 20091316
RTT 506 20091318
RTT 564 20091321
RTT 610 20091325
RTT 663 20091326
RTT 715 20091329
RTT 773 20091334
RTT 831 20091335
RTT 878 20091337
RTT 930 20091339
ACCESSORIES
For the RTT 378-930 r boilers the following accessories are avail-
able:
a. Two stage kit – 4031067
b. Storage heater probe – 20010103
Dear client,
Thank you for choosing a Rboiler, a modern and high quality
product, providing you with the utmost well-being and with a
high level of reliability and safety; and this is particularly the
case if entrusted to a RTechnical Assistance Centre which is
specically capable of carrying out routine maintenance, keep
it running at maximum efciency, with low running costs and
which has original spare parts if required.
This instruction booklet contains important information and
suggestions that should be observed for easy installation and
better use of the RTT 378-930 boiler.
Thank you once again
Riello S.p.A.
CONFORMITY
TheRTT 378-930 r boilers comply with:
−2009/142/EC (ex 90/396/EEC-Gas Directive)
−92/42/EEC (Efciency Directive)
−2006/95/EC (ex 73/23/EEC-Low voltage Directive)
−2004/108/EC (ex 89/336/EEC-Electromagnetic Compatibility
Directive)
−EN 303/1-2-3
−EN 60335-1/2
−EN55014-1/2
−EN 61000

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1.1 General warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 General characteristics of the RTT boilers.............. 5
1.3 Technical data.................................. 6
1.4 Boiler data plate .................................7
1.5 Dimensions.....................................7
1.6 Delivery........................................7
1.7 Installation of the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.8 Important information about the boiler room ......... 9
1.9 Hydraulic system................................10
1.10 Schematic diagram - system for heating and domestic
hot water production ............................10
1.11 Important instructions for connecting the fuel tank ..... 11
1.12 Important information about the ue pipe ........... 11
1.13 Control panels that can be combined ................12
1.14 High performance cast iron elements................12
1.15 Ventilation of the boiler room ......................12
1.16 Gas side resistor and output temperature of combustion
gases ........................................13
1.17 Instructions for use ..............................13
1.18 Conveyance and discharge of the boiler water .........14
1.19 Instructions for disposing of the product .............14
1.20 Fire prevention regulations for the boiler room.........14
1.21 Controls and starting the boiler.....................14
1.22 Maintenance instructions .........................15
1.23 Cleaning the boiler ..............................15
1.24 Burner door and burner connection.................16
1.25 Table of burner combinations ......................17
1.26 Transport and storage ............................18
1.27 Useful information ..............................19
CONTENTS
In some parts of the booklet, some symbols are used:
9 = for actions requiring special care and adequate preparation
0 = for actions THAT MUST NOT be performed
This booklet, Cod. Doc-0079323 - Rev. 1 (03/2016) is composed of 20 pages.

4
panel and the boiler should be carried out by qualied per-
sonnel in compliance with the reference regulations and
standards.
9 The burner should be purchased separately, this manu-
al contains only information regarding the boilers and the
boiler warranty does not extend to the burner. It is neces-
sary to consult the burner's instruction manual and have
the Warranty Certicate issued for the burner by the dealer
where it was purchase.
9 Before starting the burner, make sure that the front door of
the boiler is closed tight and that the burner connections
have been carried out correctly.
9 Do not touch the hot water pipes and the ues gases dis-
charge pipe when the boiler is running.
1.1 General warnings
The boiler models that are the subject of this manual are sup-
plied disassembled of the boiler body.
9 The cast iron RTT 378-930 boilers are designed for heating
using water and/or supplying hot water systems and have
been designed with technologies and materials suitable for
this purpose. Use the product only for this intended use.
9 The installation of the appliance should be carried out on a
base that is suited to the weight and the dimensions.
9 The base of the boiler should be positioned and oriented in
such a way as to leave sufcient space on the sides of the
appliance to meet safety requirements and permit access to
the boiler for maintenance and repairs.
9 The commissioning and initial ignition of the boiler should
only be carried out by specialised installers.
9 It is forbidden to put or pump water into the boiler or the
hydraulic system when the appliance is running and is hot.
9 Before putting water in the boiler or the system, it is neces-
sary to wait for the water temperature to reach 40° C. When
putting water into the system, always run the circulation
pump to prevent breaking the elements.
9 When the boiler is off for a long period or when carrying out
repairs, maintenance or cleaning, the electrical supply must
be disconnected using the master switch.
9 Especially in summer, when the boiler is off for a long pe-
riod, to avoid problems of incrustation in the circulation
pumps, the boiler must be switched on 1-2 times a month
and the circulation pumps operated for at least 5 minutes.
Limescale in the water can cause problems if the pump is
unused for a long period.
9 Choose a boiler with the right dimensions for the project
in full compliance with applicable regulations. If the wrong
size is chosen, the performance will suffer.
9 The RTT 378-930 boilers are only to be used for heating. For
the production of domestic hot water, it is necessary to use
a storage heater or another heat exchanger. For it to work
efciently, pay special attention to the size of the domestic
hot water circuit.
9 The RTT 378-930 boilers are delivered without the burner. To
choose the most suitable burner and keep the performance
high, contact technical personnel.
9 If the boiler goes into lockout automatically because of over-
heating, do not put cold water inside to get it going again.
Wait until the boiler cools down, and try to restart it. If this
does not happen, contact the Technical Assistance Service.
9 Periodically check the boiler and the burner. If these period-
ic controls are not carried out, performance will suffer and
there will be an increase in fuel consumption. The period-
ic and annual controls of the boiler should be carried out
carefully and at the pre-established time. Natural gas is a
clean fuel and does not dirty the appliance so much. Liquid
fuel burners, on the other hand, dirty the appliance a great
deal, and the boiler controls and maintenance operations
are necessary to ensure a high level of performance and a
long life.
9 Repairs and periodic inspections of the RTT 378-930 boilers
should be carried out by specialised technicians. This man-
ual contains an explanation of the user's responsibilities
and the information required for using the boiler. Beyond
these operations, the boiler should only be commissioned
by the user or by one of our technicians. Do not try to adjust
the boiler or tamper with any components.
9 The mains electrical connections to the boiler room, to the
burner and to the boiler itself, the earthing of the control

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1.2 General characteristics of the RTT boilers
The RTT 378-930 boilers operate with forced draught burner, they
are made of cast iron elements, provide outputs of 378 to 930
kW when connected to the burner correctly and are available
in 11 different models (from 7 to 16 elements) running on gas or
liquid fuel.
The RTT 378-930 boilers operate at a maximum pressure of 6 bar
and at a maximum temperature of 90 °C.
In the RTT 378-930 boilers, the surfaces that transfer the heat are
expanded by special ns in the burner chamber and in the ue
gas pipes. This system maximises the caloric value of the cast
iron boiler.
The RTT 378-930 boilers are boilers with cast iron elements. This
structure provides for easy assembly and allows you to increase
the capacity of the boiler by simply adding elements. Transport
and installation are simplied by the fact that the boiler is as-
sembled on site. Handling or changing its position are easy and
do not require the breaking of walls, etc.
The RTT 378-930 boilers have been produced with a special iron
alloy EN GJL 200, which provides a high degree of resistance to
corrosion and thermal expansion. This special material guaran-
tees the boilers have a long working life.
Thanks to the special horizontal gas elements with three pas-
sages, the combustion gases pass three times in the boiler ef-
fectively transferring the thermal energy to the water inside the
elements.
The RTT 378-930 boilers are high performance boilers (max. cal-
oric value 91−93% depending on the fuel used). The high level
of efciency and the perfect insulation translate into greater en-
ergy production with less fuel consumption. The RTT boilers also
provide minimal heat dispersion.
An efcient combustion chamber, a good heat transfer surface,
the turbulators, the manifold and the insulation provide a high
degree of thermal capacity and reduced discharge gas emis-
sions.

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1.3 Technical data
RTT CAST IRON
BOILER RTT 378 RTT 448 RTT 506 RTT 564 RTT 610 RTT 663 RTT 715 RTT 773 RTT 831 RTT 878 RTT 930 UM
Number of sec-
tions 6 7 8 9 10 11 12 13 14 15 16 pieces
Nominal heat
output
378 448 506 564 610 663 715 773 831 878 930 kW
325000 385000 435000 485000 525000 570000 615000 665000 715000 755000 800000 kCal/h
Nominal heat
input 410 487 551 615 665 720 777 839 900 956 1013 kW
Maximum operat-
ing temperature 90 °C
Temperature ad-
justment range 30-90 °C
Gas side resistor 1.75
2.20
1.90
2.40
2.25
2.75
2.55
3.10
2.80
3.35
3.15
3.70
3.45
4.05
3.80
4.35
4.10
4.75
4.45
4.95
4.85
5.50 mbar
Maximum operat-
ing pressure 6bar
Boiler water ca-
pacity
149.5 174 198.5 223 247.5 272 296.5 321 345.5 370 394.5 litres
0.150 0.174 0.199 0.223 0.248 0.272 0.297 0.321 0.346 0.370 0.395 m2
Diameter ue pipe
tting 350 mm
Com-
bustion
chamber
dimen-
sions
width X
length 501 mm
L910 1,070 1,230 1,390 1,550 1,710 1,870 2,030 2,190 2,350 2,510 mm
Water input-out-
put coupling G4 DN (*)
Boiler gas volume 341.74 400.71 459.68 518.65 577.62 636.59 695.56 754.53 813.5 872.47 931.44 dm3
(lt.)
0.342 0.401 0.460 0.519 0.578 0.637 0.696 0.755 0.814 0.872 0.931 m2
Combustion
chamber gas vol-
ume (gas side)
179.39 210.93 242.48 274.02 305.56 337.1 368.64 400.18 431.73 463.27 494.81 dm3
(lt.)
0.179 0.211 0.242 0.274 0.306 0.337 0.369 0.400 0.432 0.463 0.496 m2
Safety limit ther-
mostat 110 °C
Type of fuel
I2Hgas
Extra light fuel oil comb.
liquid
Flue gas-
es output
tempera-
ture
full
load 182-187 178-
185
175-
180 173-178 173-176 170-175 170-174 168-172 165-168 162-165 160-163 °C
partial
load 165-172 164-170 162-168 161-165 160-165 158-163 156-161 155-160 155-160 153-150 150-148 °C
Mass ow
of the
ue gases
full
load 633 750 848 945 1,023 1,110 1,198 1,295 1,393 1,470 1,588 kg/h
partial
load 380 450 508 567 614 666 719 777 836 882 935 kg/h
Boiler
dimen-
sions
width X
length 840 X 1355 mm
L1,300 1,460 1,620 1,780 1,940 2,100 2,260 2,420 2,580 2,740 2,900 mm
Heat loss in stand-
by
0.33 0.31 0.28 0.27 0.24 0.22 0.20 0.18 0.17 0.16 0.14 %
11583 12890 13154 14143 13608 13543 13284 12928 13127 13046 12096 kCal/h
Diameter burner
hole 225 mm
Type of burner With short head
Flue effect 5Pa
Boiler net weight 1,020 1,235 1,415 1,555 1,725 1,875 1,975 2,170 2,375 2,465 2,540 kg

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1.4 Boiler data plate
The data plate is applied to the rear of the boiler shell.
1.5 Overall dimensions
592
840
1355
L
MODEL LENGTH L (mm)
RTT 378 1,300
RTT 448 1,460
RTT 506 1,620
RTT 564 1,780
RTT 610 1,940
RTT 663 2,100
RTT 715 2,260
RTT 773 2,420
RTT 831 2,580
RTT 878 2,740
RTT 930 2,900
592
1134
250
1.6 Delivery
The boiler elements are not supplied assembled, according to
the characteristics specied and the dimensions of the instal-
lation room. The supply of the disassembled boiler provides for
the shipping of the elements and the assembly equipment on
pallets. The outer casing, the insulation and other components
are supplied inside a box. The assembly of the boiler is carried
out by technicians.
Burner box (pallet and
cardboard box)
Casing walls and insulat-
ing covering (wood box)
Cast iron boiler elements
(pallet 80x120)
Box for assembly pieces
(cardboard box)
Control panel box (card-
board box)
9 Comply with the meaning of the symbols on the packaging
for reasons of safety.

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1.7 Installation of the boiler
The dimensions of the boiler room and the free spaces should
make it easy to carry out any assembly work, repairs, re-assem-
bly and connection of the burner.
900 mm
A + 200
(min.
1000 mm)
A + 200
(min.
1000 mm)
The recommended height for the boiler room is at least 2,200
mm, leave the minimum space free on the sides and in front of
the boiler as shown in the drawing. Provide a base with a min-
imum height of 200 mm above the oor for the installation of
the burner of the boiler.
MODEL LENGTH L (mm)
RTT 378 1,300
RTT 448 1,460
RTT 506 1,620
RTT 564 1,780
RTT 610 1,940
RTT 663 2,100
RTT 715 2,260
RTT 773 2,420
RTT 831 2,580
RTT 878 2,740
RTT 930 2,900
1000 mm
200 mm
L -200 mm
L
A
Characteristics of the base:
−The concrete base should have the indicated dimensions.
−The concrete base should not be covered with a slippery
material like ceramic etc.
−Any acoustic insulation should be made before the base.
−The base should be made of BS 25 ber concrete.
0 Do not place ammable materials on the boiler or at a dis-
tance less than the specied safety distance.In the RTT boil-
ers the door of the burner can open from both sides. For
this reason, equal free distances are specied on both sides
(min. 700 mm). This characteristic is advantageous for oper-
ations to be carried out on the boiler. If the space available
in the boiler room is not sufcient for the distances indicat-
ed, you can choose the opening side and leave more space
free on that part. On the other part, half the indicated free
distance is sufcient.
Provide enough space for the tools to be used in the boiler room.

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1.8 Important information about the boiler room
9 The boiler room should be well lit and the light switches
should be located outside the room itself.
9 Place any gas detection devices at a height conforming to
regulations in force.
9 Do not place devices like the water pump, the contactor,
etc., in the boiler room.
9 Repair or replace as soon as possible any electric locks, ca-
bles, etc., that could cause short-circuits.
9 Before carrying out any welding in the boiler room, switch
off the boiler and stop the ow of ue gases by closing the
gas valve.
9 Inside the boiler room there should be no explosive, com-
bustible or inammable material.
9 The boiler room air should not contain any explosive, com-
bustible or inammable gas.
9 Children or non-technical persons should not be allowed
in the boiler room, just the person who is responsible for it.
Keep a copy of the key for the boiler room in a safe place for
emergencies.
9 It is possible to insulate the boiler room against noise and
heat, also the position and the orientation of the boiler are
important for its acoustic insulation.
9 Place the fuel tanks in another room surrounded by walls
and with adequate natural ventilation.
9 Arrange for the creation of a diversion of the water supply
line near the boiler and a drainage system for draining the
boiler water.
9 It is strongly recommended not to install extraction systems,
air conditioning system or other devices that in the boil-
er room, as a secondary effect, could cause the so-called
"vacuum effect" and reduce the draught force of the boiler,
with main consequence of damaging the burner.
9 Make sure that the boiler room receives sufcient air either
naturally or forced (using an aspirator).
9 To ensure the burner and the boiler work efciently keep the
boiler room clean and prevent the formation of humidity.
9 The boiler room should have the minimum dimensions
specied.
9 Do not store inammable material inside the room.
9 Do not touch the supply pipe tting or other hot parts of the
boiler when it is running.
9 Do not install the boiler on a rubber mat.
9 When using LPG or another liquid fuel, the boiler room,
the fuel, the system components and the hydraulic pipes
need to be in conformity with the parameters established
by European standards and by gas supplying companies.
The company is not responsible for any faults or problems
caused by inadequate or insufciently adequate conditions
for the boiler room, the hydraulic pipes and the other com-
ponents of the system.
9 Follow the instructions of your local gas suppliers.

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1.9 Hydraulic system
Limescale and other chemical substances in the water can so-
lidify producing incrustations. To prevent this happening, equip
the system with a closed expansion tank. The water that en-
ters the closed expansion tank does not evaporate and is not
dispersed. In this way the level of water in the system is kept
constant and it will not be necessary to add fresh water. In ad-
dition, limescale and dust do not form and the system will have
a longer life.
−The water contained in the radiator and in the heating
system cannot be drunk and is not suitable for domestic
use. Do not take water from the system. Add water if the
level is low.
−The hardness level of the water should be low to prevent
the formation of limescale and other chemical powders.
Quality of the water circuit water: Ph ≥7.2 Th ≤25 °Fr
−If the water from the mains is not of the required quali-
ty, after appropriate analyses it is possible to add spring
water or water from other sources. If necessary, the water
can be treated to get the desired quality.
−To prevent limescale or other powders penetrating the
boiler, or from the boiler going into the water circuit, dust
lters need to be installed at the system's input and out-
put.
−Connect the recirculation pump to the boiler output. The
power of the pump should be suitable for the boiler. Oth-
erwise, the water ow and the boiler performance may
suffer.
−To raise the temperature of the return water and to en-
sure the system runs properly, use a 4-way mixing valve
or a by-pass pump with thermostatic control.
−Connecting a 3-way motor valve between the supply line
and the return line of the heating system you can obtain
a calibrated control of the water ow towards the system.
−There must always be water in the boiler. Otherwise the
pipes and the boiler could corrode. If the boiler is not
used in winter, add an anti-freeze solution to prevent
water freezing inside the system.
REFERENCE VALUES
pH less than 7.2
Electrical conductivity less than 200 μs/cm (25°C)
Chloride ions less than 50 ppm
Sulphuric acid ions less than 50 ppm
Total iron less than 0.3 ppm
M alkalinity less than 50 ppm
Total hardness less than 25° F
Sulphur ions none
Ammonia ions none
Silicon ions less than 30 ppm
The Thermostat (1) should be installed at a distance of 3-5 diam-
eters from the connection point to the return line.
D
1
3÷5 D
3
22
3
33
4
5
3
8
10 15
10
13
14
12
1
EAF
EAF
15
6
33
33
11
67
17 5
33
3
5
3
4
3
5
3
4
SYSTEM
OUTLET
SYSTEM
RETURN
LINE
DOMESTIC
WATER
UTILITIES
DISCHARGES DISCHARGES
1 Boiler
2 System manifolds
3 Shut-off valves
4 System pumps
5 Non-return valves
6 Automatic vent valve
7 Boiler safety valve
8 Boiler discharge tap
9 Storage heater safety valve
10 Charging the system
11 System expansion tank
12 Storage heater
13 Storage heater discharge tap
14 Domestic hot water expansion
tank
15 Softener filter
16 Pressure reducer
17 Condensation pump
1.10 Schematic diagram - system for heating and domestic hot water production