Comtherm TFR Series Instruction Manual

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Installation & Maintenance Manual
TFR Burner
Burners, Heaters & Combustion Systems

TFR Burner Instruction Manual
Page.1 .............................................GeneralSpecification
Page.2 .............................................GeneralDescription
Page.3 .............................................Installation
Page.4 .............................................Installation
Page.5 .............................................Installation
Page.6 .............................................InitialLight Up (Commissioning guidance)
Page.7 .............................................InitialLight Up (Commissioning guidance)
Page.8 .............................................InitialLight Up (Commissioning guidance)
Page.9 .............................................InitialLight Up (Commissioning guidance)
Page.10 ...........................................Fault Finding Guide
Page.11 ............................................Fault Finding Guide
Page.12 ............................................Fault Finding Guide
Page.13 ............................................Fault Finding Guide
Page.14 ............................................FaultFinding Guide
Page.16 ............................................PartsList (Key)
Page.17 ............................................Suggested Service Program
Page.18 ............................................SuggestedService Program
Page.19 ............................................BurnerService program
Page.20 ............................................BurnerCommissioning Record
Page.21 ............................................Additional Commissioning Notes
Index
Comtherm Ltd
Installation & Maintenance Manual
Burners, Heaters & Combustion Systems

The 'TFR' series of packagedgas burnershave beenspecificallydesigned forthe firingof
immersion tubes installed in liquid tanks.
The TFR burnersare intendedfor application to small bore tube applicationswith tube
diametersup to 200mm in diameter.
The TFR burner head has been specially developed for small bore applicationsand is
availablefor firing into immersiontubes with diametersup to 200mm.
The TFR burner uses asplit combustion cone headwhereairis introducedinto the flame at
threepoints and providescooling for the combustion tubes.
TFR burners canbe supplied for inputs rangingfrom 35kW to 750kW.
Dependingon immersion tube selection TFR burnerapplicationscan producethermal
efficiencies of over 75% and 80% respectively.
BURNER ASSEMBLIES
Each burnerunit is supplied with a packagedand pre-pipedvalve assembly,including the
safety valves and controls necessary to form a fully pre-packagedcombustion module.
Burner assemblies normally include automatic flame safety and ignition equipment.
Burnersbuilt to special specificationsdependingon applicationand country of installation
can be fitted.
Burner packages are fully tested and the operationof all components checked before
despatch from the factory.
TYPES OF CONTROL AVAILABLE
Burnersarenormallysuppliedsuitable for on-off control with slowopening safety shut off and
control valves.
If required modulation control or high-low controlled burnerscan be supplied.
Condensationof productsof combustion in the tubes limits the turndownrangeavailable
when high-low or modulation control is used.
General Specification
Comtherm Ltd
Installation & Maintenance Manual
Page 01
Burners, Heaters & Combustion Systems

The burner consists of a nozzle assembly having fuel and air jets designed to produce
effective mixingof the fuel andcombustionair hence providinggood flame stability. The
nozzle assembly is fitted with integral ignition and flame sensor facilities.
The unit comes complete with all the valves and controls required;forming a fully packed, safe
burnerassembly.
The valves and controls are pre-piped and mounted on the burner,as illustrated
diagrammaticallyin document M4. Pressure test points are fitted between valves where
necessary.
The physicalarrangementof the burneris shownin diagramform on document M3 (where
applicable).
All the electricalequipment on the unit is pre-wiredto a terminalenclosurebuilt into the burner
assembly,as detailed in the burnerwiring diagramincluded on document M5.
The electrical operation of the burner is as follows:
When the electrical supply is switched on to the burner and all the control circuits are closed,
the burner light up sequence is initiated.
The burner flame safety sequence control unit (unit A1) receives the electrical start signal and
begins to cycle through an air pre-purgeand light up sequence.
The air pre-purgeis for a specified, preset time and allows for dilution of any fuel leakage;to
safeguardagainstthe possibilityof explosive fuel/air mixturebeing presentin the firing
chamber whenthe ignition is energized.After the completion of the pre-purge,the ignition
and flame proving period take place.
When the flame signalis proven,the burner sequencecontrol remainsin the operating
position until any of the control circuit interlocks arebroken or a flame failure(lockout)
condition occurs.
Complete details of the burner light-up sequence including the flame safety control unit (item
A1) will be found in the component data sheet, enclosed.
For details on installation see pages 3-5 and for commissioning refer to pages6-9.
NOTE: See page16 forkey to items referredto throughoutthis manual. Refer to documents
M1, M3, M4, M5, M9 sent with contract for specific component manufacturersused on this
equipment.
General Description
Comtherm Ltd
Installation & Maintenance Manual Page 02
Burners, Heaters & Combustion Systems

Before proceedingwith the installation of the burner,inspect the burnerfor any physical
damagethat may have occurredduring transit, storage or off-loading.Any damageshould
be reported immediately.
The pipe work or gas valves on the burner should not be used for lifting under any
circumstances,as this tends to pull fittings loose or damagevalves, causing leaks during later
operation.
Mount the burner in the firing position, makingsurethat adequatespace is allowed around
the burnerfor ventilation andthat the combustion air inlet is not blocked.
Ensure that an adequatefresh air supply is available for combustion and general ventilation.
Situations wheregas from valve and pipe work leaks can collect and form pockets of
combustible gas/air must be avoided.
Ensurethat adequatespace is allowed aroundthe burner for easy access to allburner
components, pressureswitches, control operatorsetc.
The burner should be securely fixed and the transmission of vibration and heat should be
minimised.
GAS SUPPLY:
Gas piping to the burnershould be of sufficient size to providethe correct gas pressureat the
burner valve assembly inlet (see specification in document M1).
If in any doubt concerningthe sizeand designof thegas supply pipework, consult the gas
supply company.
The pressureloss in the gas supply pipe work should be such that the following pipeline
velocities arenot exceeded:
Unfiltered supply 20M/s (65.6ft.sec)
Filtered supply (250microns) 45M/s (148ft.sec)
The above stated velocities are based on the avoidance of excessive noise pollution and
erosion.
Installation
Comtherm Ltd
Installation & Maintenance Manual
Page 03
Burners, Heaters & Combustion Systems

For low-pressuresuppliesup to 25 mbar (10 w.c), the pressuredropbetweenthe meterand
the burner inlet should normally not exceed 1mbar (0.4 w.c).
For high-pressuresupplies,this pressuredropshould not exceed 10% of the availablegas
pressure.
A manual shut off valve followedbya union or flangedjoint should beincorporatedin the
Gas supply pipe adjacent to the burner,this valve permits isolation of the supply and removal
of the burner assembly for maintenance purposes.
The manual shut off valve should be easily accessible.
Do not use the burner valve assemblyto support the gas supply pipework. Suitable brackets
or hangersshould be used for this purpose.
Before connecting the gas supply check that the available gas pressure is correct (see
specification in document M1).
Check that the gas supply system has been designed and installed to ensure that during fault
conditions, pressuresin excess of the maximum designratingof the equipment cannot be
reached.
If the burneris installed in a confinedspaceconsiderationshould betaken forthe fitting of a
vent pipe to the breatherholes of governors.
Vents from governorsmust not bemanifoldedand shouldterminate ina safe place,preferably
above roof level.
Any additional vent pipes that are required will be shown in document M4.
The gas supply pipe will be full of air and will require purging.
This purgingshould only be carried out by a suitably qualified gas engineer.
With regardto the soundness (leak) testing andpurgingof the supply pipework ensurethat a
certificate exists stating that this work has been completed in accordancewith technical
publications EN 746-1 and 2.
Installation (Continued)
Comtherm Ltd
Installation & Maintenance Manual Page 04
Burners, Heaters & Combustion Systems

After completion of the installationwork, the procedure for testing for gasleaks on the burner
detailed in the manual section pages10-15, should be completed and any leaks repaired.
The burnershould be left with the manualshut off valve (item V1) in the closed position until
the plant is commissioned by a suitably qualifiedgas engineer.
ELECTRICAL SUPPLY:
Burnerscan be suppliedto suit almost all types of electrical power supply; includingall
common industrial three phase (50 or 60Hz) powersupplies and with 110/120v or
220/240v control circuits. Burners to suit otherelectrical supplyvoltages can besupplied
speciallyto suit specific applicationrequirements.
All wiringon the burnershould comply with the requirementsof the local electricalcodes of
practice.
All conduits shouldbe kept clearof heat zones.
Local means of electrical isolation should be installed close to the burner.
Ensurethat the electrical voltage does not vary from the specified bymorethan 6%.
High temperaturewire (tri-rated or better) should be used for all electrical connections.
The electrical connections to the burnershownon the diagramin document M5 should be
strictly adheredto.
Gas pipe work shouldnot be used as an electrical earth.
Installation (Continued)
Comtherm Ltd
Installation & Maintenance Manual
Page 05
Burners, Heaters & Combustion Systems
.

PLEASE NOTE:
Without exception, burners should only be commissioned by suitably qualified
personnel. The following notes are intended as guidance and in no way negate the
need for the equipment to be commissioned by suitably qualified personnel.
1. Examine the burner for physicaldamage.
2. Close all manual fuel valves.
3. Check that the electrical supply is switched off.
4. Check all electrical connections to ensure that the combustion air pressure switch (item P1)
and the safety shut off valve (item S1) arewiredto the correct terminals in the burner
safety control unit (see electrical diagramin document M5)
5. Check the incoming gas pressure (at V1) and verify that the inlet gas pressure is as
specified (see page M1).Generally speaking, the inlet gas pressure, without the burner
operating,will be somewhat higher than when the burner is in operation.
6. Ensure that the burner on/off switch is in the position.
7. Switch the electrical supply on.
8. Check for gasleaks on the burner as follows:
(a) Close the manual valve V1 and pilot manual valve V6.
(b) Vent burner pipe work downstream of V1 by opening a suitably positioned test
nipple.
(c) Use a manometer test pressure downstream of V1 for 1.5 minutes. If no pressure
buildsup, valve V1 is not leaking.
(d) Open valve V1.
(e) Check for external leakage using a soap solution or gasdetector on
pipe work and valves, rectifying any leaks before proceeding.
(f) Put temporary electricalsupply onto valve S1.This will pressurise the space
between S1 and S2. Open the test point downstream of S2 and connect the
manometer (valve V2 must be closed); if no pressure builds up within 1.5 minutes then
valve S2 is sound.
Initial Light Up (Commissioning)
Comtherm Ltd
Installation & Maintenance Manual Page 06
Burners, Heaters & Combustion Systems

(g) Disconnect the electrical supply to valve S1 and vent the space
between valve S1 and S2, using the pressuretest nipple.Using the
manometer, check that no pressure builds up between the two valves; if no pressure
is detected then valve S1 is sound
(h) Open pilot manual valve V6 and check by using the test nipple downstream of V1
that there is no pressure drop at this point. If no pressure drop is detected in 1.5
minutes then valve S3 is not leaking.
(i) Finally, check downstream of V2 and V3 with soap solution or gas detector (with
burner running).
In cases where burners are fitted with main multi-block / combination safety valve units, the
above procedure will vary; the valve should be energized to check for downstream pipe
leakages and de-energised followed by venting of downstream pipe space to check for valve
seat leakages.
9. Release the spring pressure on the gas governor (item G2).
10.Set the combustion air pressure switch (item P1) 25% below the specified air pressure
required.
11. Start the fan supplying the combustion air and ensure that the fan rotation direction is
correct.
Check the running current of the motor and crosscheck this with the data on the Motor label.
Ensure that the motor overload protection is correctly set.
12.Ensure that valves V2 and V6 areclosed.
13.Check that all pressure switches associated with the burner are in the correct position.
Note that the burner combustion air pressure switch (item P1) should be in the
position and should only switch over after the combustion air fan has started
14. Check that all pressure switches associated with the burnerare in the position calling
for and switch the burner on.It may be necessary to reset the burnerlockout fault button.
Initial Light Up (Commissioning)
Comtherm Ltd
Installation & Maintenance Manual
Page 07
Burners, Heaters & Combustion Systems

15.Allow the flame safety control unit (item A1) to cycle through the start up sequence; check
that the pressure switch (P1) has changed over from the `no to the air proved position.
If it adjust the combustion air supply so as to provide satisfactory burner air
pressure. Check that the ignition and pilot solenoid valves are electrically energised at the
correct time and in the correct sequence. The burner flame safety control unit should then
lockout.
16.Open the manualpilot valve (item V6)
17.Fit Micro-ammeter into circuit with the flame sensor.
18.Reset the burner lockout button; the burner will cycle and the pilot flame should light. It
may be necessary to start the light up sequence (reset) several times so as to remove air
from the pilot line and to adjust the pilot flame to the correct size. Check the pilot flame
signal on the micro-ammeter.
19.Note that the burnerwill go to lockout after each attempt to light the pilot.
20.Half open the manual test valve (item V2). Reset the burner lockout button. The burner
should cycle and light up onto the main flame.
21.Slowly open up the manual test valve (item V2) to the full position and adjust the main gas
governor (item G2) to produce the required flame size. With the burner on full fire
(temperature control calling heat) check that the gas pressure at the nozzle is as specified
for the required thermal/fuel rating, this will be indicated on the burner data label and
can also be established from the nozzle flow graph included with this manual.
22.Check the main flame signal on the micro-ammeter.
23.Turn the combustion air pressure switch (item P1) upwards so that the burner shuts down.
Note the adjustments in air pressureand reduce the switch setting by 25%.
24.Whilst the burner is operating remove the electrical connections from the flame sensor.
Check that the burner flame safety control locks out immediately and that the gas supply is
automatically shut off.
25. Whilst the burner is operating, block the combustion air supply so that the pressure switch
P1 switches to the position, checking that the burner shuts down.
Initial Light Up (Commissioning)
Comtherm Ltd
Installation & Maintenance Manual Page 08
Burners, Heaters & Combustion Systems

26.Check the operation of all control and safety devices in the burnercontrol circuits.
In addition, ensure that the burner operates correctly. Make a note of all control settings.
27. The low fire setting of the burner should be made in line with the process requirements
whilst still maintaining a steady flame signal.
NOTE;-
Once correctly commissioned the burner settings should only be altered by suitably
qualified personnel, and only when changes to the process requirements deem it
necessary. At no point should the settings of any safety device be altered to overcome
changes in process conditions without the burner again being fully commissioned in line
with those process conditions.
Initial Light Up (Commissioning)
Comtherm Ltd
Installation & Maintenance Manual
Page 09
Burners, Heaters & Combustion Systems

FIND FAULT
POSSIBLE CAUSES
SOLUTION
Burner light up
sequence does not
start
No electrical supply Check electrical supplyat
local isolator.
Check the control fuse
Burner electrical control
condition
Check controls and switches
in control circuit
Check all pressure switches
and micro-switches
Airflow pressureswitch not
made Check setting on switch, if this is correctcheck airflow
Low gas pressure switch
not made Check setting on switch if this is correctcheck thegas
pressure
Start cycle begins but
the burner locks out or
shuts down before
initiating the ignition
sequence
Low combustion air
pressuredifferential Reset burnerpressureswitch (P1)
If pressureswitch P1 is set
correctly open the air damper
on the combustion air fan
Check that the combustion air
fan motor is rotatingin the
correctdirection
Check that the combustion air
fan is running,if not check the
overload or circuit breakers
Fault Finding Guide
Comtherm Ltd
Installation & Maintenance Manual Page 10
Burners, Heaters & Combustion Systems

FIND FAULT
POSSIBLE CAUSES
SOLUTION
Pilot does not light No spark Check electricalsupply to
ignition transformer
Check electrical connection
to spark plug
Check operationof ignition
transformer
Check condition of spark
plug and clean, reset or
replace
No pilot gas Check manualvalve is open
Check that pilot solenoid
valve opens
Ensure gasis availableat
burner
Not enough pilot gas Check pilot gas flow adjuster
and pilot gas regulator
Pilot blown out Reduce process air flow if
possible
Increase pilot gas rate
Pilot lights but locks
out when ignition de-
energised
Pilot gas rate too low Adjust pilot gas rate
Pilot lights but the
burner locks out before
the main valves are
energised
Flame sensor not detecting
the flame
Or
Faulty sensor
Check sensor for damageor
moisture
Clean flame sensor
Check flame sensor
installation and position
Replacesensor
Fault Finding Guide
Comtherm Ltd
Installation & Maintenance Manual
Page 11
Burners, Heaters & Combustion Systems

FIND FAULT
POSSIBLE CAUSES
SOLUTION
Main flame does not
light and burner locks
out at the end of the
pilot phase
Faulty main shut off valve Check electricalsupplyto
valve
Check conditionof the valve,
if faulty, replaces
No main gas Check manualvalve open
Check the adjustment of the
gas control valve
Ensure gasis availableat
burner
Not enough main gas Check main gas flow adjuster
and main gas regulator
Main flame lights but
shuts down after a short
periodof time
Pilot gas rate too high Adjust pilot gas rate
Control circuit operating Check control circuit, over
temperature
limits etc.
Burner gas or air ports
blocked Check and Clean Identifysourceof blockage
and rectify
Flame sensor not detecting
the
flame
Over firing and flameis
firing rate
Check flame sensor
installation and position
Check the main gas pressure
governor
Fault Finding Guide
Comtherm Ltd
nstallation & Maintenance Manual Page 12
Burners, Heaters & Combustion Systems

FIND FAULT
POSSIBLE CAUSES
SOLUTION
Flame failure (lockout)
during normal main
flame operation
Faulty main shut off valve Check electricalsupplyto
valve
Check conditionof the valve
if faulty, replace
No main gas Check manualvalve is open
Check the adjustment of the
gas control valve
Ensure gasis availableat
burner
Not enough main gas Check main gas flow adjuster
and main gas regulator
Low fire set too low Check and adjust
Control circuit operating Check control circuit, over
temperature
limits etc.
Burner gas or air ports
blocked Check and Clean Identifysourceof blockage
and rectify
Flame sensor not detecting
the flame
Combustion air failure
Over firing and flameis
firing rate
Check flame sensor
installation and position
Inspect combustion air fan for
damage
Check fan overloads
Check air filter (if fitted) and
clean if necessary
Fault Finding Guide
Comtherm Ltd
Installation & Maintenance Manual
Page 13
Burners, Heaters & Combustion Systems

FIND FAULT
POSSIBLE CAUSES
SOLUTION
Flame failure (lockout)
at low fire Faulty low fire bypass valve (high low burners only) Low fireflame set too low Check electrical supply to
valve
Check condition ofthe valve
if faulty, replace
Low fireflame set too low Check the adjustment of the
gas control valve
Ensure gas is available at
burner
Too much air Check and reset air at high and
low fire
Low fire air set too low
(modulating gas and air
burnersonly)
Check and adjust
Control circuit operating
due to Check control circuit, over temperaturelimits and low fire
settings
Flame sensor not detecting
Flame Check flame sensor installation and position
Main flame too long Too much gas
Check main gas pressure and
reset
Check gas control valve and
reset
Check fuel type
Combustion air set too low Check air dampers,linkages
and air filter (where fitted)
Fault Finding Guide
Comtherm Ltd
Installation & Maintenance Manual Page 14
Burners, Heaters & Combustion Systems

FIND FAULT
POSSIBLE CAUSES
SOLUTION
Red
.
Low process airflow.
Reset air.
Main flame too long.
Check the adjustment of the gas
control valve.
Combustion airset too low.
Check air dampers,linkages and
air filter (where fitted).
Unit will not achieve
temperature.
Too much process air.
Check and reset air.
Burner input setting too low.
Check and reset Burner.
Leakage of cold air into
system.
Source and rectify.
Burner shuts down (see
also sheets M8.1 to
M8.4b).
Control circuit operating.
Check control circuit, process
airflowswitch, over temperature
limits and low firesettings.
Flame sensor not detecting
the flame.
Check flame sensor installation
and position.
Too much pressurein
chamber.
Check Flue.
Unit Produces
condensation.
Burner turned downtoo
low.
Check the adjustment of the gas
control valve.
Low processair volume.
Check and reset air.
Fault Finding Guide
(Indirect Heaters)
Burners, Heaters & Combustion Systems
Page 15 Comtherm Ltd
Installation & Maintenance Manual

Parts List (Key)
A1: Flame control unit
A2: Flame electrode
A3: U.V. flame sensor
A4: Valve proving unit
B1: Burner combustionhead
B2: Peep sight
B3: Viewing window
B4: Inspection plate
C1: Burner fancontactor/overload
C2: Processairfan contactor/overload
E1: Ignition transformer
E2: Ignition plug
E3: Burner on-off switch
E4: Low fire position microswitch
E5: High fire position microswitch
E6: Closed positionindicatorswitch
E7: Isolator
E8: Terminal box
E9: Purgetimer
ET: 24v Control transformer
EB: Alarm Bell
EFS: Exhaust flow switch
FC: Control circuit fuse
FB: Burner control fuse
F1: Burner motor fuse
F2: Process air fan fuse
G1: Primarygas regulator(high pressure)
G2: Main gas governor
G3: Primary pilot gas governor (high pressure)
G5: Over pressureslam shut valve
G6: Pressurereliefvalve
K1: Push button burner start
K2: Push button burner stop
K3: Push button lockout reset
K4: Push button fault reset
K5: Push button alarm mute
K6: Push button valve provingfault reset
K7: Push button Flame signal test
L1: Indication light burnerlockout
L2: Indicationlight burner run
L3: Indicationlight valve fault
L4: Indicationlight power on
L5: Indicationlight instruments on
L6: Indication light burner fan failure
L7: Indicationlight burner fanrun
L9: indicationlight processfanrun
L10: indicationlight exhaust fan run
MF: Burner fan
M1: Burner fan motor
M2: Burner fan impellor
P1: Burner fanpressure switch
P2: Process air pressureswitch
P3: Low gas pressureswitch
P4: High gas pressureswitch
P5: Valve provingpressureswitch
P8: Gas pressure gauge
P9: Air pressuregauge
R: Electrical relay
S1: First safety shut off valve
S2: Second safety shut off valve
S3: First pilot/start gas solenoidvalve
S4: Second pilot/start gas solenoidvalve
S5: Vent valve (normal open)
S6: Threeway solenoid valve -burner air
SM: Solenoid/governor multi-bloc valve
TC: Control instrument
TL: High limit thermostat or sensor
T3: Valve positioner
T4: Valve actuator
T5: Control supply transformer
V1: Manual inlet valve
V2: Manual test valve
V3: Gas filter
V4: Vent cock
V5: Gas control valve
V6: Pilot manualgas valve
V7: Pilot gas adjustment
V8: Gauge cock
V9: Air flow control valve
V10: Gas flow adjustment
V11: Air flow adjustment
V12: Air filter
V13: Oil filter
V14: Oil control valve
V15: Gas orifice plate
Inclusion of this list does not imply that all items are included in the particular equipment to which this refers: refer to sheets M3 (if
applicable), M4 and M5 for details. Refer to recommended spares list for actual complete parts specification.
Burners, Heaters & Combustion Systems
Page 16

The burner is designed to allow quick and easy preventative maintenance by removal
of the burner back door.
The exact timing of service work to the burners can only be determined based on the
ambient working environment of each specific installation; as a minimum however we would
suggest that the following service points are covered at least on a half yearly basis and should
only becarriedout by suitably qualifiedpersonnel;
1. Remove burner back door.
2. Remove spark electrode, clean with wire brush and check plug gap setting of 2.5 to
3mm.
Inspect plug ceramic for any cracks or damage.
3. a. Remove flame sensing electrode, clean electrode with emery paper and inspect
plug ceramic for any cracksor damage.
Or
b. Remove U.V. cell and clean bulb with clean cloth; taking care to not touch the bulb
itself.
4. Remove combustion fan motor and impellor, clear impellor blades of any blockage or
build-up of materialdrawnin by the fan.
5. Clear fan inlet guard of any blockage or restriction, if the combustion air is ducted to
the fan assembly then the duct should be removed to check for any blockage.
6. Clear burner body of any dirt or debris which has been drawn in by the combustion
fan.
7. Un-bolt and remove the inner gas manifold / nozzle / air cone and inspect front face
of nozzle and air cone for serious damage, small cracks and fishers or very slight
distortion in the air cone would not be detrimental to the operationof the burner.
When replacing the inner assembly a suitable sealant should be applied to its joint
with the inlet gas manifold.
8. All pressureswitch impulse lines should be removed and checked for any blockage.
Suggested Service Program
Burners, Heaters & Combustion Systems
Page 17 Comtherm Ltd
Installation & Maintenance Manual

Suggested Service Program
Burners, Heaters & Combustion Systems
Page 18
Comtherm Ltd
Installation & Maintenance Manual
9. This down time with the burner should also be used to check the integrity and correct
operation of safety pressure switches and solenoids.
10. The burner valve assembly should also be checked at this time for gasleaks.
11. Finally all burner gas and air settings should be checked against the last recorded
commissioning or service settings. The burner should not be put back into operation until
test firing has been carried out by the engineerperformingthe service.
Under no circumstances should the settings of any safety devices be changed from those
recorded in the last commissioning data unless this is being carried out as a complete re-
commissioning of the burner to facilitate changes in process requirements; the re-
commissioning of the burner should only be carriedout by suitably qualifiedpersonnel.
If the ambient conditions are particularly dirty then we would suggest carrying out a full
service on a quarterly basis.