baltur comist 36 Instruction Download

Page: 55 / 140

55 / 139

0006080093_00709

proceed as follows:

1) Ensure that combustion waste can

be discharged without any hin-
drance (chimney gate open) and
that there is water in the boiler.

) Open the combustion air re-

gulator (see BT 8653/1) to the
extent considered necessary
and open to about one third the
air passage between blast tube

and disk, using the flame disk

adjustment screw.

3) Operate the relief valve and “first

flame” regulators so that desired

quantity (start-up flow rate) of gas

in supplied.

N.B.

See end pages for detailed

description of gas supply adjust-
ment depending on type of valve

fitted to burner.

4) Switch off the second flame ther

mostat and switch on the burner
by operating main  and burner
(natural gas setting) switches. In
this way the burner is cut-in and
carries  out  the  pre-ventilation
phase. If the air pressure control
pressure switch reads pressure
above  its  preset  value,  first
switch  on  the  ignition  transfor-
mer and then the gas valves (re-

lief and first flame). The valves

open fully is limited to the setting

to which the flow rate regulator

(built-into the first flame valve

(pilot) has been manually set.

On first ignition, further “blocks”

can occur due to insufficient air

clearance of gas pipes. There
is therefore not enough gas to

give a stable flame. A “Block”

with flame present can also be

caused by flame instability due

to incorrect air/gas ratio. This
can be remedied by varying
quantity of air/gas supplied in or-

der to find correct ratio. This can

be  remedied  by  operating  the
blast  tube  adjustment  device,
closing (unscrew the blast tube
position adjustment screw in the
case of COMIST 36 and move
forward  the  blast  tube  fixing
knobs  in  the  case  of  COMIST
7 and COMIST 1) or opening
(screw the blast tube adjustment

screw in the case of COMIST 36
and move backward the blast

tube fixing knobs in the case of

COMIST 7 and COMIST 1)
more the air passage between

blast tube and flame disk (see

BT 8608/1 and BT 8608/3).

5) While burner is operating, adjust

supply to desired value for “first

flame” (natural gas = 8550 kcal/

), taking a reading at the me-

ter. This flow rate can be modified

by using the regulator built-into
the valve, as described above.

6) Check that combustion occurs

correctly (use the appropriate
instruments). Maximum permitted
level of carbon monoxide (CO) is
0,1% whereas permitted range for
carbon dioxide (CO

) is 8 ÷ 10%.

7) After adjusting, switch burner on

and off several times to check
that ignition is correct.

8) Switch off burner via the main

switch to make a direct (brid-
ge) connection between the

terminals of the second flame

thermostat. Adjust combustion
air to setting considered suitable

for switch-on of second flame

(see BT 8653/1). Also open the

gas flow regulator (built-into the

second valve) to obtain a sup-
ply considered suitable for the

main flame and set the 1st and

nd stage switch in “nd stage”
position.

9) Now switch on main switch to

ignite burner. While burner is

operating on second flame, che

ck gas supply (meter reading) as
previously described. Depending
on readings, adjust gas supply if
necessary,  to  adapt  it  to  actual
value  required  (boiler  output).
Using suitable instruments, che-
ck  that  combustion  is  correct
(CO

= 8 ÷ 10 % for natural gas

- CO max. = 0,1%). To improve

combustion and for good flame

stability  (no  pulsations)  it  may
be  necessary  to  operate  the
blast  tube  adjustment  device.
If  burner  operates  on  low  fuel
supply, the air passage between
disk  and  blast  tube  should  be

reduced (unscrew the blast tube
position adjustment screw in the
case  of  COMIST  36  and  move
forward  the  blast  tube  fixing
knobs  in  the  case  of  COMIST
7 and COMIST 1). When the
burner  is  operating  at  a  higher
fuel  supply  level,  this  passage
should  be  opened  proportiona-
tely (screw the blast tube position
adjustment screw in the case of
COMIST 36 and move backward

the blast tube fixing knobs in the

case of COMIST 36 and move

backward the blast tube fixing

knobs in the case of COMIST 7

and COMIST 122). If flame disk

position is modified, it is usually

also necessary first to correct

the positions of the first and se

cond flame air regulation gates.

Then, check that ignition is
correct.

SAFETY CHECKS

After adjusting, always check the
following:

1) Burner stop: open air and gas ther-
mostats and pressure switches.

) “Blocking”: shadow the photocell
(UV).

To unblock, push the appropriate
button.

TENANCE

At the end of the heating season,
it is good practice to clean the gas

and light oil filters, the combustion

head (disk, insulators, nozzles), the
combustion air passages and the
photoelectric cell (UV). It is advisa-
ble to use wooden or plastic instru-
ments to clean the nozzle passages.
Nozzle should be replaced after 1
months’ use.

UV CELL

If flame detection is carried out with

the UV cell, the following should be
taken  into  consideration.  Even  the
slightest greasiness will compromise
the  passage  of  the  ultraviolet  rays
through  the  UV  photoelectric  cell