Bentone BENTOFLEX ST 120 KAV Technical specifications

Providing
sustainable
energy
solutions worldwide
178 038 16-2 2017-10–04
Installation- and maintenance instruction
BENTOFLEX ST 120 KAV

DESCRIPTION
1. Reset button
2. Control box
3. Ignition transformer
4. Ignition cables
5. Nozzle assembly
6. Nozzle
7. Brake plate
8. Blast tube
9. Ignition electrodes
10. Connecting pipe
11. Air damper
12. Solenoid valve
13. Pump
14. Drive coupling
15. Indication, air damper
16. Fan wheel
17. Adjustment, air damper
18. Photoresistor
19. Motor
171 205 32 07-01
Components

Dimensions
2,7-3,3 0,5-1,5
8,0-9,0
171 225 24 08-01
TECHNICAL DATA
Electrode adjustment
Because of different boiler types
existing on the market, with varying
combustion chamber designs, it is

angle or spray pattern.
Recommended nozzle
Note that the spray angle and the
spray pattern change with the pump
pressure.
Output range and nozzles recommended

Burner tube Length of burner
tube

Measure B

Measure B

Measure B

Measure B
KAV 147 109 122 130 129
KAV 224 186 199 207 206
Burner tube Oil capacity Capacity Recommended
Nozzle
Recommended Pump
pressure
   Angle Type Bar
KAV 2,0-5,6 24-66 20-57 60°, 80° H, S 10
B
148
ø89
54
169
229
194
275
ST 120 KAV

TECHNICAL DATA
171 215 76 07-01
Flange A
10,3
25
130-150
ø89,7
Flange C
10
125
ø90 4
Flange D
125-150
10,3
ø90 5
12
Flange B
ø89,5 12
136-150
Dimensions

General rules
The installation of an oil burner should
be carried out in accordance with local
regulations. The installer of the burner
must therefore be aware of all regula-
tions relating to oil and combustion.
Only oil suitable for the burner should
be used and then in combination with

of the burner.
If the burner is replacing an existing

replaced or cleaned. The installation
must only be undertaken by expe-
rienced personnel. Care should be
taken by the installer to ensure that no

trapped or damaged during installation

Installation instructions
General installation instructions ac-
company the burner and should be
left in a prominent place adjacent to
the burner.
Adjustment of burner
The burner is from the factory pre-set
to an average value that must then be
adjusted to the boiler in question.
All burner adjustments must be made
in accordance with boiler manufactu-
rers instructions.These must include

average water temperature and CO2
or O2concentration.
To adjust the combustion device,
start by increasing the air volume
somewhat.

with excess air and smoke number
0. Reduce the air volume until soot
occurs and increase again to reach
a combustion free of soot.
By this procedure an optimum adjust-
ment is obtained. If larger nozzles
are used the preadjustment of the air
volume must be increased.
Condensation in chimney
A modern burner works with less
excess air and often also with smal-
ler nozzles than older models. This

risk of condensation in the chimney.
The risk increases if the area of the
-

60°C measured 0,5 metres from the
chimney top.
Pump adjustment
See separate description.
Adjustment of burner
To obtain a correct adjustment a

measurement must be carried out.
Otherwise there is a risk that a bad
adjustment may cause a formation of

the chimney.
Maintenance

regularly for any signs of malfunction
or oil leakage.
GENERAL INSTRUCTIONS
Measures to raise the temperature:
Insulate the chimney in cold attics
Install a tube in the chimney
Install a draught regulator (dilutes the

them up during standstill)
Increase the oil quantity
     
removing turbulators, if any, in the
boiler.
Instructions for use
The end user of the burner should be
instructed about the operation and
safety features of the burner.
He should also be made aware of
the importance of the area around
     
combustible material.
Air adjustment 0 - 32
171 305 69 07-01
Adjustment of nozzle assembly 0 - 22

MAINTENANCE OF OIL BURNER
Warning: Before doing any service switch off power at the main switch and cut off the oil supply
171 305 68 07-01
Service of burner head and nozzle assembly

171 415 21 07-01
List of components
A1 Oil burner control
A2 Twin thermostat
E1 Preheater
F1 Fuse, max. 10A
H1 Alarm lamp
H2 Signal lamp (optional)
M1Burner motor
P1 Time meter (optional)
R1 Photoresistor
S3 Main switch
T1 Ignition transformer
Y1 Solenoid valve
X1 Plug-in contact, burner
X2 Plug-in contact, boiler
The colours of the preheater cable:
A Blue
B Brown
C Black
*
(1)(2)
Outer electrical connection
Wiring diagram
* If there is no plug-in contact (X2) on the boiler, connect to the contact
enclosed. In case the twin thermostat is in series on incoming phase
L1, a loop between the terminals T1 and T2 is necessary.
Mains connection and fuses in
accordance with local regulations.
ELECTRIC EQUIPMENT
Oil burner control: LOA21... / LOA24..
With preheater.
X1
X2
1(2)

171 415 21 07-01
Function
1. Switch on operating switch and twin thermostat
Voltage is applied to the preheater and the preheating period starts.
This period lasts till the operating temperature of the oil has been
reached and the preheater thermostat closes (2).
2. Preheater thermostat closes
The burner motor starts, an ignition spark is formed, the prepurge goes
on till the prepurge period expires and the solenoid valve opens (3).
3. Solenoid valve opens

(1) 
(2)  
ignition transformer is connected to terminal 7 (LOA24.173...).
4. The safety time expires
  
  
burner will make an attempt to re-start.
4-5. Operating position
If the burner operation is interrupted by means of the main switch or the
thermostat, a new start takes place when the conditions in accordance
 
The oil burner control cuts out
A red lamp in the control is lit. Press the reset button and the burner
re-starts.
Post-ignition
(2) If a post-ignition of 15 s. is wanted, move the ignition transformer
from terminal 7 to terminal 6 (LOA24.173...).
Technical data
Pre-ignition time: 13 s
Pre-purge time: 13 s
(1) Post-ignition time: 15 s
(2) Post-ignition time: 2 s
Safety lock-out time: 10 s
Reset time after lockout: ≈50 s
 
Ambient temperature: from - 20 to +60°C
 
  
Enclosure: IP 40
(Under voltage proof only LOA24...)
Control of photo current
Current through photo unit is measured with a d.c. ammeter
(a moving coil instrument connected in series with the photo unit).
ELECTRIC EQUIPMENT
Oil burner control: LOA21... / LOA24..
With preheater.
2(2)

INSTRUCTIONS PUMP TYPE DANFOSS BFP41
Components
 
2. Pressure gauge port
3. Pressure adjustment, 4mm allen key
 



8. Return plug
Technical data
Viscosity range: 1,3-12,0 mm2
Pressure range: 7-15 bar
Oil temperature: -10 to +70°C
Suction line tables
The suction line tables consist of
theoretically calculated values where
the pipe dimensions and oil velocity
have been matched so that turbulences
will not occur. Such turbulences will
result in increased pressure losses and
in acoustic noise in the pipe system. In
addition to drawn copper piping a pipe
system usually comprises 4 elbows, a
non-return valve, a cut-off valve and an

The sum of these individual resistances
      
disregarded. The tables do not include
any lengths exceeding 100 m as
experience shows that longer lengths
are not needed.
The tables apply to a standard fuel
oil of normal commercial quality
according to current standards. On
commissioning with an empty tube
system the oil pump should not be
run without oil for more than 5 min.
(a condition is that the pump is being
lubricated during operation).
The tables state the total suction line
length in metres at a nozzle capacity

pressure at the suction and pressure
side is 2,0 bar.
Purging
On 1-pipe systems it is necessary to
purge the pump. On 2-pipe systems
purging is automatic through the
return line.
171 505 07 10-01
Two-pipe system
Height Pipe diameter
H ø6 mm ø8 mm ø10 mm
m m m m
0 17 53 100
-0,5 15 47 100
-1,0 13 41 99
-1,5 11 34 84
-2,0 9 28 68
-2,5 7 22 53
-3,0 5 15 37
-3,5 3 9 22
4,0 1 3 6
Height Pipe diameter
H ø4 mm ø5 mm ø6 mm
m m m m
Height Pipe diameter
H ø6 mm ø8 mm ø10 mm
m m m m
4,0 33 100 100
3,5 31 98 100
3,0 29 91 100
2,5 27 85 100
2,0 25 79 100
1,5 23 72 100
1,0 21 66 100
0,5 19 60 100
Height Pipe diameter
H ø4 mm ø5 mm ø6 mm
m m m m
4,0 51 100 100
3,5 45 100 100
3,0 38 94 100
2,5 32 78 100
2,0 26 62 100
1,5 19 47 97
1,0 13 31 65
0,5 6 16 32
1-pipe system 1-pipe system

system is not recommended
Two-pipe system
H
H

Function Danfoss BFP41
   
drawn from the suction connection

side of the gear wheel (C).
The gear wheel then pumps oil to the
pressure side and the oil is put under
pressure.
The pressure is controlled and kept
constant at the set value by the
regulating valve (P1) with the
diaphragm (D).
The regulating valve (P1) distributes
the oil quantity supplied by the gear set
(C) between the nozzle port (E) and
the return side of the pump (R).
The oil quantity utilized is determined
by the set pressure on the regulating
valve (P1) and the size of the oil nozzle
in the nozzle line.
The valve (P1) functions in the following
way:
 
been reached, the passage to the
return side opens.
- The diaphragm and the spring
keep the pump pressure constant
at set value.
- If the pump is overloaded, i.e. if
you try to get out more
oil than the gear set can supply
under existing circum-stances, the
oil pressure falls below the set value
and the valve closes against the
return side (R) by means of the
diaphragm(D)andgoesintostarting
position.
This can be remedied by:
- Reducing the pump pressure.
- Reducing the oil quantity supplied
by using a smaller nozzle.
- Using a pump with a larger capacity.
171 505 08 07-01

Burner with preheating
Consider that the oil quantity is
reduced at preheating by 5-20%
depending on.
- Rise in temperature at the nozzle
- Nozzle design
- Capacity (high capacity - small
difference)
Mounting/dismounting return plug

from plug
     
the cover by means of a 4 mm allen

necessary, put a screwdriver between
 


and replace it by a new one. Press it
on to the plug. Ensure that the


One pipe system Two pipe system
R
S
E
NC
A
G
H
V
P1
P
D
C
INSTRUCTIONS PUMP TYPE DANFOSS BFP41

171 505 44 07-01
Gph 8 9 10 11
           
0,40 1,33 16 13 1,41 17 14 1,49 18 15 1,56 18 16
0,50 1,66 20 17 1,76 21 18 1,86 22 19 1,95 23 20
0,60 2,00 24 20 2,12 25 22 2,23 26 23 2,34 28 24
0,65 2,16 26 22 2,29 27 23 2,42 29 25 2,54 30 26
0,75 2,49 29 25 2,65 31 27 2,79 33 28 2,93 35 30
0,85 2,83 33 29 3,00 36 31 3,16 37 32 3,32 39 34
1,00 3,33 39 34 3,53 42 36 3,72 44 38 3,90 46 40
1,10 3,66 43 37 3,88 46 39 4,09 48 42 4,29 51 44
1,20 3,99 47 41 4,24 50 43 4,47 53 46 4,68 55 48
1,25 4,16 49 42 4,40 52 45 4,65 55 47 4,88 58 50
1,35 4,49 53 46 4,76 56 48 5,02 59 51 5,27 62 54
1,50 4,98 59 51 5,29 63 54 5,58 66 57 5,85 69 60
1,65 5,49 65 56 5,82 69 59 6,14 73 63 6,44 76 66
1,75 5,82 69 59 6,18 73 63 6,51 77 66 6,83 81 70
2,00 6,65 79 68 7,06 84 72 7,45 88 76 7,81 93 80
2,25 7,49 89 76 7,94 94 81 8,38 99 85 8,78 104 89
2,50 8,32 99 85 8,82 105 90 9,31 110 95 9,76 116 99
2,75 9,15 108 93 9,71 115 99 10,24 121 104 10,73 127 109
3,00 9,98 118 102 10,59 126 108 11,16 132 114 11,71 139 119
3,50 11,65 138 119 12,35 146 126 13,03 154 133 13,66 162 139
4,00 13,31 158 136 14,12 167 144 14,89 176 152 15,62 185 159
4,50 14,97 177 153 15,88 188 162 16,75 198 171 17,57 208 179
5,00 16,64 197 170 17,65 209 180 18,62 221 190 19,52 231 199
5,50 18,30 217 187 19,42 230 198 20,48 243 209 21,47 255 219
6,00 19,97 237 204 21,18 251 216 22,34 265 228 23,42 278 239
6,50 21,63 256 220 22,94 272 234 24,20 287 247 25,37 301 259
7,00 23,29 276 237 24,71 293 252 26,06 309 266 27,33 324 279
7,50 24,96 296 254 26,47 314 270 27,92 331 285 29,28 347 298
8,00 26,62 316 271 28,24 335 288 29,79 353 304 31,23 370 318
8,50 28,28 335 288 30,00 356 306 31,65 375 323 33,18 393 338
9,00 29,95 355 305 31,77 377 324 33,59 398 342 35,14 417 358
NOZZLE TABLE
Pump pressure bar
The table applies to oil with a viscosity of 4,4 mm23.
Burner with preheater
Consider that on preheating the oil quantity is reduced by 5-20% depending on.
- Rise in temperature at the nozzle
- Design of nozzle
- Capacity (high capacity - small difference)
1(2)

171 505 44 07-01
Gph 12 13 14 15
           
0,40 1,63 19 17 1,70 20 17 1,76 21 18 1,82 21 18
0,50 2,04 24 21 2,12 25 22 2,20 26 22 2,28 27 23
0,60 2,45 29 25 2,55 30 26 2,64 31 27 2,73 32 28
0,65 2,65 31 27 2,75 33 28 2,86 34 29 2,96 35 30
0,75 3,08 36 31 3,18 38 32 3,30 39 34 3,42 40 35
0,85 3,47 41 35 3,61 43 37 3,74 44 38 3,87 46 39
1,00 4,08 48 42 4,24 50 43 4,40 52 45 4,56 54 46
1,10 4,48 53 46 4,67 55 48 4,84 57 49 5,01 59 51
1,20 4,89 58 50 5,09 60 52 5,29 63 54 5,47 65 56
1,25 5,10 60 52 5,30 63 54 5,51 65 56 5,70 68 58
1,35 5,50 65 56 5,73 68 58 5,95 70 61 6,15 73 63
1,50 6,11 72 62 6,36 75 65 6,60 78 67 6,83 81 70
1,65 6,73 80 69 7,00 83 71 7,27 86 74 7,52 89 77
1,75 7,14 85 73 7,42 88 76 7,71 91 79 7,97 94 81
2,00 8,18 97 83 8,49 101 86 8,81 104 90 9,12 108 93
2,25 9,18 109 94 9,55 113 97 9,91 117 101 10,26 122 105
2,50 10,19 121 104 10,61 126 108 11,01 130 112 11,39 135 116
2,75 11,21 133 114 11,67 138 119 12,11 144 123 12,53 148 128
3,00 12,23 145 125 12,73 151 130 13,21 157 135 13,67 162 139
3,50 14,27 169 145 14,85 176 151 15,42 183 157 15,95 189 163
4,00 16,31 193 166 16,97 201 173 17,62 209 180 18,23 216 186
4,50 18,35 217 187 19,10 226 195 19,82 235 202 20,51 243 209
5,00 20,39 242 208 21,22 251 216 22,03 261 225 22,79 270 232
5,50 22,43 266 229 23,34 277 238 24,23 287 247 25,07 297 256
6,00 24,47 290 249 25,46 302 260 26,43 313 269 27,49 326 280
6,50 26,51 314 270 27,58 327 281 28,63 339 292 29,63 351 302
7,00 28,55 338 291 29,70 352 303 30,84 366 314 31,91 378 325
7,50 30,59 363 312 31,83 377 324 33,04 392 337 34,19 405 349
8,00 32,63 387 333 33,95 403 346 35,25 418 359 36,47 432 372
8,50 34,66 411 353 36,07 428 368 37,45 444 382 38,74 459 395
9,00 36,71 435 374 38,19 453 389 39,65 470 404 41,02 486 418
NOZZLE TABLE
The table applies to oil with a viscosity of 4,4 mm23.
Burner with preheater
Consider that on preheating the oil quantity is reduced by 5-20% depending on.
- Rise in temperature at the nozzle
- Design of nozzle
- Capacity (high capacity - small difference)
2(2)
Pump pressure bar

FAULT LOCATION
Burner fails to start
Delayed ignition, burners starts violently
Burner fails to start after normal operation
Situation
Motor runs
Burner pre-purges
Flame occurs
Burner locks out
Motor runs
Burner pre-purges

Burner locks out
Possible causes
Flame instability
Incorrect head settings
Low oil pressure
Excess air
Photocell not seeing light
Photocell failed
Control faulty
False light
No spark
No oil
Remedies
Check nozzle to burner head dimension
and electrode position
Check oil pressure
Adjust air damper
Check that photocell is clean and
unobstructed


advisable to change the photocell if also
changing control)
Check that photocell is not seeing
ambient light
Check that H.T. leads are sound and are
not arcing other than at electrode gap
Check oil supply to burner - check that
pump is not airlocked
Check operation of magnetic valve
Burner fails to start
Lamp not lit
Motor runs
Burner runs to lockout
Fuse has blown
Appliance thermostat has not reset
Appliance overheat device has operated
Control relay or photocell defective
No oil being delivered

 
No spark
Check or replace fuse if necessary.
Check reason for failure
Adjust thermostat
Reset overheat device. Find reason for
its operation and rectify
Check by replacement

and nozzle are all in good order
Rectify condition
Check ignition transformer. Check
electrode gap and porcelain
Burner pulsates on start-up

Burner pulsates on start-up
Burner starts violently
Excessive draught
Nozzle partly blocked
Oil pressure too low
Flue blocked or damaged
Fan slipping on shaft
Pump coupling loose or worn
Delayed ignition
Adjust the burner
Replace nozzle
Check and adjust
Check and rectify
Check and retighten
Check and replace
Check the electrode adjustment, see
diagram
Check electrodes for damage
Check H.T. leads for damage and
disconnection
171 915 01 08-01

OIL BURNERS MAINTENANCE
INSTRUCTIONS
General information
Keep the boiler room clean. Ensure that the boiler
room has permanent fresh air intake. Switch off before
dismantling the oil burner.
At hinged mounting, make sure that an automatic safety
switch is fitted, so that the burner cannot start when
theswing door is open.
Don´t use the oil fired boiler to burn paper or
rubbish,unless the boiler is especially fitted with a hinged
door tomake this possible.
Don´t fill tank while burner is working.
Starting precautions
Make sure that the oil tank is not empty
Make sure that the valves on oil and water supply pipes
areopen.
Make sure that the boiler flue damper is open.
Make sure that the boiler thermostat is set at the correct
temperature.
Switch on the current. Most relay systems have a
delayed action so that the burner will not start for
perhaps 20 seconds.
With heavy oil the delay will be longer as the burner
will notstart until the oil in the preheater reaches the
requiredtemperature.
If the burner will not start
Press the reset button on the relay. Check that the
thermostats are correctly adjusted.
Don´t forget the room thermostat, check that any
fusesare intact and main switch is on.
If the burner starts but does not ignite
Make an attempt to start the burner.
Never make close repeated start attempts.
Don´t restart the burner until the boiler is free from oil
gases.
If the burner still does not ignite send for the service
engineer.
When switching off during summer
Always use the main switch to cut out the burner even
when adjusting the burner or cutting off the heating for
ashort time. For longer periods of shut down, close all
valves and the oil supply stop-cock.
Clean the filter and nozzle by washing in petrol or
paraffin.
Make sure the filter medium is not damaged or defective.
Protect electrical gear from damp.
Warning
Never stand too near or put your face to the inspection
or fire door, when the burner is about to start.
Never use a naked flame to ignite oil if the electrical
ignition fails.
Always wait for about 10 minutes for the unburnt gases
to disperse before restarting the oil burner if it has failed
to ignite previously.
Installed by:
Tel:
170 025 01 2012-04-16

Enertech AB. P.O Box 309, SE-341 26 Ljungby.
www.bentone.se, www.bentone.com