Bentone STG 146, Installation And Maintenance Instructions Manual

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 manufacturers 

instructions. These must include the 

checking  of  flue  gas  temperatures, 

average water temperature and CO

2

or O

2

 concentration

General instructions

The installation of the gas burner must 

be carried out in accordance with 

current regulations and standards. The 

installers of gas burners should therfore 

be acquainted with all regulations and  

ensure that the installation complies 

with the requirements. The installation, 

mounting and adjustment should be  

made with the greatest care and only 

the correct gas should be used.

Operating instructions

The operating instructions accompa-

nying the burner should be left in 

a prominent position in the boiler 

room.

Instructions

The user should be thoroughly 

instructed in the function of the gas 

burner and the whole installation. The 

supplier must instruct the user.

Inspection and maintenance

Daily inspection is advisable.

Service

Service  should  only  be  carried  out 

by qualified personell. Replacement 

parts should be of the same make and 

approved by the same authorities as 

the original. If the burner is converted 

to fire another gas quality it must be 

re-commissioned. If town gas is to be 

fired  the  combustion  head  must  be 

converted and the  gas train adjusted 

to suit, (e.g.a larger gas armature or 

a different spring in the governor may 

be required).

Start up

After  the  burner  has  been  fitted  to 

the boiler and the electric connection, 

the leakage control, the venting and 

the electric function test have been 

carried out, the burner will be ready 

for start-up.
Hower, study the sections dealing 

with adjustments of  multi-bloc, 

combustion air and combustion 

head.

172 305 52  07-01

GENERAL INSTRUCTIONS

Open the ball valve and switch on the 

main switch. If the burner starts the 

actual adjustment can be made.

Air adjustment

On all burners the air adjustment can 

be  made  with  or  without  the  cover 

fitted. Final fine adjustment must be 

made with the cover on.

Adjustment of burner head

The burners are equipped with an 

adjustment  device  changing  the 

position of the brake plate in the burner 

head. This is used to adjust the corect 

pressure  drop  over  the  combustion 

device  and  thereby  obtain  a  good 

pulsation free combustion. 
Which position to use depends on 

input and overpressure in the boiler.

A general rule is that the lower capacity 

the smaller the opening between brake 

plate and combustion device.

Adjustment of brake plate

–

Turn by means of an allen key the  

  screw in the desired direction.
 

STG120/1, STG120/2, STG146/1

–

To reduce the opening: turn the  

  screw to the left.

–

To increase the opening: turn the  

  screw to the right.

  STG146/2

–

To reduce the opening: turn the  

  screw to the right.

–

To increase the opening: turn the  

  screw to the left.

The adjustment of the position of the  

brake plate affects the air flow. It is 

therefore always necessary to make a 

fine adjustment of the air by means of 

the adjustment device of the burner.

Control of burner head

To check the burner head, brake plate 

and electrodes proceed as follows:

Remove the cover. Loosen the union 

nut between inner assembly and multi-

bloc. Loosen the burner from the 

flange and withdraw the burner from 

the boiler. If it is necessary to remove 

the burner tube, loosen the two allen 

screws, turn and withdraw the burner 

tube.

Commissioning of installation

Control of the combustion. The 

combustion quality is checked by 

means of a flue gas analysis device. 

Adjust the burner to appr. 20% excess 

air in accordance with the table. Check 

the flue gas temperature. Calculate 

the efficiency. Check also the actual 

gas volume on the  gas meter so that 

the correct input is achieved.

Gas quality

CO

2

% 

lambda 1,2

0

2

%

max CO

2

%

Natural gas

10,0

3,5

11,9

LPG

11,5

3,5

13,9