Riello RDB2 Installation guide

15–20 kW
20–26 kW
29–36 kW
Please read these instructions carefully
before commissioning and using this appliance.
To be retained by the householder
Burner Setup Details
Riello RDB2

2
HEALTH AND SAFETY
INFORMATION FOR THE USER, INSTALLER AND SERVICE ENGINEER
Under the Consumer Protection Act 1987 and the Health and Safety at Work Act 1974, it is a
requirement to provide information on substances hazardous to health (COSHH Regulations
1998).
Trianco takes every reasonable care to ensure that its products are designed and constructed to
meet these safety requirements when the products are properly installed and used. To fulfil the
requirements, products are comprehensively tested and examined before despatch.
When working on the appliance, it is the responsibility of the user or engineer to ensure that
personal protective clothing or equipment—appropriate to parts that could be considered
hazardous or harmful—is worn.
This appliance may contain some of the items below:
Insulation and Seals
Glass rope, mineral wool, insulation pads, ceramic fibre, glass insulation.
When handling, avoid inhalation and contact with eyes. These may be harmful and cause
irritation to the skin, eyes, nose or throat. Use disposable gloves, face masks and eye protection.
After handling, wash hands and other exposed areas. When disposing of materials, limit dust and
the risk of inhalation by using a water spray. Ensure materials are securely wrapped.
Seek urgent medical attention if inhaled or ingested. Exposure to eyes and skin should be
followed by immediate cleansing of the affected areas and medical attention if necessary.
Glues, Sealants and Paints
The glues, sealants and paints used present no known hazards when the appliance is used in the
manner for which it is intended.
Mineral Oils
The appliance is designed to run on 28 sec. kerosene class C2. The effects of mineral oils on the
skin will vary depending on the length of exposure.
Avoid any skin contact with oil or clothing contaminated with oil. Kerosene will remove the
protective grease normally present on the surface of the skin, rendering it dry, liable to cracking
and more prone to damage caused by cuts and abrasions. Seek immediate medical attention for
any rash, wart or sore that develops on any part of the body.
Barrier cream that contains lanolin, such as Rosalex Antisolv is recommended together with a
strict regime of personal cleaning.
Do not breath oil vapours. Do not fire the burner in the open (i.e. out of the boiler) as a misfire will
produce unburned oil vapours. Under no circumstances should mineral oils be taken internally.

3
CONTENTS
Page no.
Technical specifications
4
Burner setup
4
Combustion air / adjustment
5
Oil pump
6
Nozzle replacement
7
Electrode positions
8
Burner removal
8
Control box wiring / removal
9
Fault-finding
10–11
Spares
12–13

4
Model
Riello RDB2
Ignition
8 kV / 16 mA
Electrical supply
230/280 V –50 Hz fused at 5A
Control box
RBL 535 SE/LD analogue
Motor
RBL 90W
Pump
RBL
Rpm
2,700
Fuel
Kerosene C2
Capacitor
4.5 mF
Output
Input
Nozzle
Pump
pressure
Primary air
damper
Secondary
air damper
CO2
15.0 kW·h
50,000 Btu·h
15.5 kW·h
52,860 Btu·h
0.45 x 60ºES
110 psi
7.6 bar
B
2.0
11.0%
17.5 kW·h*
60,000 Btu·h
19.1 kW·h
64,993 Btu·h
0.5 x 80ºEH
130 psi
9 bar
B
4.0
11.3%
20.5 kW·h
70,000 Btu·h
22.1 kW·h
75,528 Btu·h
0.6 x 80ºEH
130 psi
9 bar
C
4.0
11.5%
20.5 kW·h
70,000 Btu·h
22.1 kW·h
75,528 Btu·h
0.6 x 80ºEH
130 psi
9 bar
C
3.0
11.5%
23.4 kW·h*
80,000 Btu·h
25.0 kW·h
85,350 Btu·h
0.65 x 80ºEH
135 psi
9.3 bar
C
5.0
11.5%
26.3 kW·h
90,000 Btu·h
28.3 kW·h
96,374 Btu·h
0.75 x 80ºEH
135 psi
9.7 bar
D
5.5
11.5%
29.0 kW·h
100,000 Btu·h
31.5 kW·h
107,441 Btu·h
0.85 x 80ºEH
130 psi
9 bar
C
4.5
12.0%
32.8 kW·h*
112,000 Btu·h
35.3 kW·h
120,500 Btu·h
1.0 x 80ºEH
110 psi
7.6 bar
E
4.0
12.0%
36.0 kW·h
125,000 Btu·h
39.2 kW·h
133,712 Btu·h
1.1 x 80ºEH
125 psi
9 bar
E
4.5
12.0%
Note 1 The primary air damper should remain at the position indicated. The secondary air damper settings are
for guidance only; individual site conditions—such as the type of flue and level of draught—will often compel
deviation from the recommended positions. See fig 3 for air damper adjustment instructions.
Note 2 The CO2ratio is correct for a combustion air temperature of 20°C; see fig 2 for other temperatures.
Note 3 The *indicates factory settings. To attain different outputs, changes to the nozzle specification, pump
pressure and air setting may be required. The boiler should be set to match the heat requirements of the
system. Incorrect matching may impede the boiler's correct operation and invalidate its warranty.
BURNER SETUP
Fig 1
TECHNICAL SPECIFICATIONS

5
To set the primary air damper (A), remove the secondary air damper (B) by loosening the screws (1).
Loosen the primary air wheel screw (2) and rotate the primary damper to the required position. Retighten the
screw and replace the secondary damper.
To set the secondary air damper (B), turn the adjustment screw (3) either clockwise (+) or anti-clockwise (–)
using the Allen key provided. The air setting will be indicated in the display window.
COMBUSTION AIR
AIR DAMPER ADJUSTMENT
To conform to Efficiency Directive
92/42/EEC, the concentrations of
CO and CO2in the flue gases must
be verified. As combustion air can
be taken from the room in which the
boiler is situated or from outside,
there may be variations in the ratio
depending on the combustion air
temperature. Use the graph
adjacent to set the correct level.
Example: a 29–36 kW boiler taking
in combustion air at 20°C will
require a CO2ratio of 12%
Fig 2
Fig 3

6
OIL PUMP
If the burner goes to a lock-out state due to a lack of oil pressure, the pump may require priming. Remove
the pressure gauge bleed port plug until oil is seen to be present and replace the plug.
Single-pipe systems
Where the lowermost part of the tank is above the level of the oil pump, a single-pipe gravity system can
be used. The supply pipe should be connected to the suction port on the burner pump via the flexible hose
(supplied). The pump is pre-set to run on single-pipe oil supplies—the bypass screw (3) must not be
present in the return line (see fig 4).
Two-pipe systems
Where the lowermost part of the tank is below the level of the burner, a two-pipe suction lift is necessary. A
second flexible hose will be required, and the oil pump must first be converted for use. Remove the return
line plug (2), insert the bypass screw (3) and connect a second flexible oil line (not supplied).
Single pipe oil supplies with a de-aerator
Where a two-pipe suction lift is required, but it is not feasible to fit a return pipe, an oil de-aerator can be
used. The burner should be piped—and the pump converted—as for a two-pipe system, up to the de-
aerator, at which point a single pipe can be taken to the storage tank. The de-aerator should be fitted as
close to the boiler as possible—though externally to the premises—at a height no lower than the oil pump.
Fig 4
1 –Suction line
2 –Return line
3 –Bypass screw
4 –Pressure gauge connection /
air bleed point
5 –Pressure adjustment
6 –Suction gauge connection
7 –Solenoid valve
8 –Auxiliary pressure test point

7
1. Switch off the electrical supply to the burner
and isolate the oil supply.
2. Remove the burner plug from the boiler
control box.
3. Remove the burner from the boiler (fig 8).
4. Remove the blast tube (fig 5), exposing the
nozzle holder assembly.
5. Taking care not to damage the electrodes,
remove the nozzle with an appropriate
socket or box spanner (fig 6)
6. Fit a new nozzle of the same specification.
7. Replace the flame ring in the same position,
check the electrode positions (fig 7) and
tighten.
8. Refit the blast tube.
Fig 5
Fig 6
NOZZLE REPLACEMENT
1 –Blast tube retaining screws (x2)
2 –Oil pump
3 –Control box
4 –Reset button / light
5 –Mounting flange / gasket
6 –Air damper fine tuning
7 –Pump pressure adjustment
8 –Pressure gauge connection
9 –Photocell

8
Fig 8
ELECTRODE POSITIONS
BURNER REMOVAL
Fixed Head
Important:
Before removing or assembling
the nozzle, loosen the screw (B)
and move the electrodes ahead.
Fig 7
To remove the burner (2), unscrew the nut that holds it to the mounting flange (1) and pull
away, leaving the mounting flange and gasket (5) attached to the boiler (4). To remove /
replace the flange and gasket, undo the retaining nuts (3).

9
CONTROL BOX WIRING
Fig 9 RBL 535 SE/LD Analogue
CONTROL BOX REMOVAL
HS –Mains switch
ST –Limit thermostat
RT –Control thermostat
Fig 10
To remove the control box:
1 –Loosen the screw (1) and open lid (2).
2 –Remove all components.
3 –Remove the solenoid valve (3).
4 –Loosen the two retaining screws (4).
5 –Disconnect the ignition leads and
remove the control box.

10
Note: before making any electrical checks or modifications, ensure the mains supply to the boiler is switched off.
Fault
Possible cause
Action
Burner will not start
Control box locked out
Press red reset button on burner
High limit stat tripped
Press red reset button on rear of control panel;
check function of boiler stat
System controls satisfied
Ensure that all controls are calling for heat
Blown fuse
Fit new fuse (5A); if problem persists, look for short
circuits in the wiring
Motor or pump seized
Check for rotation; replace as necessary
Burner starts but flame will not
establish
No oil supply
Check oil levels in storage tank; check for
adequate flow through the oil supply pipes
Air trapped in pump or oil line
Bleed excess air from the pump via the pressure
gauge connection
Solenoid coil not opening
Check coil for continuity; replace as necessary
Blocked nozzle
Replace the nozzle
Electrodes incorrectly set
Reset gap and position to dimensions given
Electrode insulation cracked
Replace as necessary
Faulty ignition leads
Replace as necessary
Low oil pressure
Check pump pressure and adjust to level given
Flame establishes but cuts out after
a few seconds
Oil contaminated with water
Run oil from drain cock at tank until free of water
Oil filter partially blocked
Wash filter clean with kerosene
Faulty photocell or photocell not seeing
flame
Clean photocell; check for damage; ensure it is
fully inserted; replace as necessary
Low oil pressure
Check pump pressure and adjust
Morning start lock-out
Faulty non-return valve or air leak
Replace non-return valve; repair leak
Low voltage to the boiler
Check with electricity supplier to remedy
Incorrect combustion settings
Check combustion under normal running
conditions; set air intake and oil pressure
Oil in storage tank below level of burner
Raise tank or fit two-pipe oil supply
Delayed ignition (burner pulsates)
Nozzle partially blocked
Replace nozzle
Low oil pressure
Check pump pressure and adjust
Flue blocked or damaged
Check flue; replace/repair as necessary
Fan slipping on shaft
Check fan; replace/repair as necessary
Pump coupling loose or worn
Check coupling; replace/repair as necessary
Burner starts violently
Electrodes incorrectly set
Reset electrode gap and position to dimensions
given in burner details leaflet
Electrodes damaged
Replace as necessary
Faulty ignition leads
Replace as necessary
Burner repeatedly attempts to fire
(balanced-flue only)
Exhaust gas in combustion air
Repair/replace leaking flue sections as necessary;
check for obstructions close to the terminal
Combustion fumes smell
Combustion chamber access cover not
secure
Tighten nuts; replace seal as necessary
Burner incorrectly fitted or gasket
damaged
Tighten burner to boiler; replace seal as necessary
Flue incorrectly fitted or gasket damaged
Tighten mounting nuts; replace seal as necessary
BURNER FAULT-FINDING