Limpsfield LC Series, Operating And Maintenance Manual

Page 1: ...impsfield Combustion Engineering Limited Unit 10 Airport industrial estate Wireless Way Biggin Hill Kent United Kingdom TN16 3BW Tel 01144 1959 576633 Fax 01144 1959 576644 E mail enquiries limpsfield co uk Web www limpsfield co uk ...

Page 2: ...Burner Technical data 2 Component Information 3 Gas manifold 4 Oil gun assembly 5 Electrode settings 6 Burner installation 7 Typical UL Gas control Train 8 Typical Oil Train 9 General start up procedure for all fuels 10 Service recommendations 11 General burner servicing procedure 12 Fault finding 13 Commissioning Report 14 ...

Page 3: ...Section 1 Legal statements and Disclaimers Burner assembly area ...

Page 4: ...d approved technicians engineers Various training schemes can be arranged at or our works or on site with suitably qualified personnel by prior arrangement with our service support department All personnel working on boilers combustion system should hold suitable qualifications in an appropriate discipline All personnel should have received training from the relevant manufacturer All personnel sho...

Page 5: ...ys contact the manufacturer for advice if in any doubt of your particular requirements It is therefore vitally important that any of the following works 1 Servicing 2 Inspections 3 Remedial Breakdown Works 4 System Modification and Enhancements be carried out by qualified and experienced technicians who have received training from the manufacturer If in any doubt as to the technical proficiency of...

Page 6: ...Recirculation FGR Systems 6 Air Filters Fans and Silencers 7 Gas Pressure Control Rigs 8 Flues and Exhaust Ducts 9 Level Controls and Blowdown Systems 10 Refractory Insulation 11 Burner Ignition and Flame Safeguard Systems Any abnormal occurrence or condition on the system must be investigated by a trained and technically competent person who has been trained by the manufacturer of the relevant eq...

Page 7: ...Section 2 Burner Technical Data Gas flame firing at 12 300 000 btu hr ...

Page 8: ...40 570 Inches 9 45 9 45 9 45 13 97 13 97 17 32 17 32 22 44 Mounting hole Ø MM 8 5 8 5 8 5 10 5 10 5 10 5 10 5 17 Inches 0 33 0 33 0 33 0 41 0 41 0 41 0 41 0 67 Quantity of mounting holes 4 4 4 8 8 8 8 8 Burner Type Number 88 100 123 150 175 200 263 310 Burner Rating Mw 8 8 10 12 3 15 17 5 20 26 3 31 Mmbtu 30 35 42 50 60 70 90 110 Air at 15 Excess Cuft hr 334 650 390 425 468 510 557 750 669 300 780...

Page 9: ...Section 3 Component Information General assembled burner ...

Page 10: ... Damper 8 Rear Burner Wind box 9 Front Burner Wind box 10 Blast Tube Assembly 11 Terminal Box Assembly Transformer Mounting Bracket 12 Terminal Box 13 Ignition Transformer 14 Normally Closed Oil Solenoid Valves 15 Fuel Servo Motor 16 Oil Metering Valve 17 Gas Control valve Lc9 15 screwed type Lc21 310 flanged type 18 Gas Nipple Lc9 15 only Note The above diagram is a general arrangement for illust...

Page 11: ...Section 4 Gas Manifold assembly Split gas head assembly ...

Page 12: ... Warning Ensure all electrical power is removed prior to servicing equipment Step 1 Remove all sight glass fastening screws item 1 on the diagrams above and remove the sight glass assembly item 2 from the burner Step 2 Remove the 4 fixings for the gas manifold from gas manifold mounting plate item 5 Pull the electrode wires not shown and carefully remove manifold assembly item 3 from the burner bl...

Page 13: ...removed the service person has access to the adjustable orifice plate item 8 Step 1 If the burner is equipped with a proven gas pilot Lc21 310 the pilot injector disc must be removed Loosen set screw to allow for removal of the pilot injector disc assembly figure 4 Step 2 Remove 3 ea Diffuser fastening screws item 7 and diffuser stand off pillars item5 Step 3 Loosen 3 ea Jam screw washer item 4 on...

Page 14: ... gap setting will change the gas flow rate hence gas pressure from their original values DECREASING the gap will allow less gas flow per the same pressure Likewise INCREASING the gap will allow more gas flow per the same pressure Thus the burner fuel air ratio may change and require alterations to be made from the original commissioned values Refer to the Autoflame Technical Manual and the Single ...

Page 15: ...ugs in an internal combustion engine This should be carried out as follows Remove the gas head assembly from burner Feeler gauges should first be selected for the correct injector setting In this case 1mm The injector should be loosened off and the feeler gauge inserted between the injector and pipe The injector should then be pushed up against the feeler gauge and locked in position It is importa...

Page 16: ...Section 5 Oil Gun assembly Oil nozzle and lance assembly ...

Page 17: ...es bypass nozzle requires approximately 300 psi 20 bar of oil supply to the nozzle Bypass pressures at high and low fire for a 4 1 turndown are approximately 220 psi 16 bar and 60 psi 4 bar respectively Oil Gun Retaining Screws Nozzle Flow Pipe Oil Lance Support Collar KC2 Oil Nozzle Carrier KC2 BypassNozzle Nozzle Return Pipe ...

Page 18: ... drip after burner shutdown This feature requires approximately 75 psi 5 bar of oil pressure at the nozzle to open Upon initial commissioning of oil the commissioning engineer may have to close the spillback metering valve an incremental amount if ignition does not take place The opening pressure can be measured with a 0 600 psi 0 40 bar oil pressure gauge via the pressure port in the spillback me...

Page 19: ...Section 6 Electrode settings Pilot injector and ignition setup ...

Page 20: ...fold prior to the gas metering valve At the proper sequence the ignition transformer energizes and a spark is generated at the electrode tips located directly above the orifice plate gap At this time the pilot gas is ignited and may burn behind the diffuser Once the main gas valves energize main ignition takes place and the gas should move from behind the diffuser and retain to the diffuser face T...

Page 21: ...the source of the main gas ignition A critical element in proper burner light off not only is related to pilot gas supply pressure but also the position of the ignition electrode The figure above illustrates proper ignition electrode gap setting This setting should be kept to approximately 1 8 or 3mm Electrodes should be kept clean and checked periodically for proper adjustment Pilot Injector Disc...

Page 22: ...Section 7 Burner Installation Limpsfield LC9 dual fuel burners on Hurst boilers ...

Page 23: ... 70 National Electrical Code Please contact Limpsfield Engineering Technical Help for clarification on any of the above Contact Limpsfield s engineering department for installation technical information as each burner is engineered to suit each site application and a general arrangement drawing is created and submitted to the customer for application approval for height width length dimensions and...

Page 24: ...Sample Typical fire tube installation ...

Page 25: ...Typical water tube installation ...

Page 26: ... sizes from several manufacturers This allows for proper air delivery in both volume and pressure for installations of high altitude elevated furnace pressures and varying ambient conditions which affect fan performance Thus blower arrangement is dependant upon jobsite conditions which must be known at the time of placing the order The installation arrangement of the blower is dependant upon many ...

Page 27: ... of the duct so that 2 off NPT pipe nipples schedule 40 can be fitted to either end one for the air pressure switch to be mounted to and the other 1 4 nipple to be Beveled as shown in figure 4 above to an angle of 45 degree angle and then positioned in line with the airflow stream The low pressure sensing line vacuum connection of a differential pressure switch should be connected before the high ...

Page 28: ...umstances should the boiler room be subject to a negative pressure It is generally accepted that square inch of free air opening for each burner within the boiler room per 1000 BTU hr Authority relating to combustion air and boiler room ventilation requirements vary widely and in order to make certain of compliance the controlling authorities should be consulted and to NFPA 31 to ensure all necess...

Page 29: ...Section 8 Typical Gas control Train 2 gas control train assembled ...

Page 30: ... shutoff valve for leakage testing locked oe sealed open L Leakage test connection M Gas Meter optional N Drip leg Q High gas pressure switch R Low gas pressure switch S Pressure gauge T Manual shutoff valve X Low fire start switch Safety shutdown interlocks not shown Flame detector s Excessive steam back pressure interlock excessive water temperature and pressure interlock for hot water boilers A...

Page 31: ...Typical Gas Train Note it is important that gas trains adhere to your local codes and requirements Schematic of a typical gas train Lc9 15 Schematic of a typical gas train Lc21 310 ...

Page 32: ...Section 9 Typical Oil Train Assembled oil pump with filter ...

Page 33: ...Typical No2 Oil Train Note It is important that oil trains adhere to local codes and requirements Maximum return pressure of 2psi Figure 1 Typical Light Fuel Oil Hydraulic Schematic ...

Page 34: ...Typical No6 Oil Train Pressure Atomising Note It is important that oil trains adhere to local codes and requirements Figure 2 Typical Heavy Fuel Oil Hydraulic Schematic ...

Page 35: ...Typical No6 Oil Train Air Atomising Note It is important that oil trains adhere to local codes and requirements Figure 3 Typical Heavy Fuel Oil Hydraulic Schematic ...

Page 36: ...Section 10 General start up procedure ...

Page 37: ...Manual to ensure that the correct amount of oil is input in to the boiler furnace The oil throughput can be measured by an oil meter or the absence of an oil meter the throughput can be checked by supply and spillback oil pressures Procedures in general 1 Check and inspect that all burner package equipment has been installed correctly and the installation has been completed this includes gas and o...

Page 38: ...afeguard in order that when operating and modulating under normal conditions the same safe and efficient combustion is met at all times The servo motors controlling the air and fuel Gas or Oil should be set to achieve a smooth and reliable light off every time once this is achieved the burner flame will modulate to meet the boiler load demand based on the settings programmed and entered by the tra...

Page 39: ...ves still in the manually off closed position to check the shut off safety of the burner package 9 The pilot and main gas lines should be purged of air carried out in accordance with NFPA 54 and then all valves shut off and pipe work reconnected in readiness for firing burners 10 All gas pipe work should be pressure checked for gas soundness we advise that a bubble leak test is also carried out on...

Page 40: ...re due to the Autoflame flame safeguard internal PID the burner will turn back on at the pre determined set point set by the trained technician 24 If water levels are fitted to the boiler steam applications the boiler should be blown down to check the operation of the water level controls When the water falls below the set water level the burner should turn off and restart automatically when the w...

Page 41: ...cycle this time the pilot valves will open and gas will flow to the ignition assembly and pilot should be established It is advisable to restart the burner to make sure the pilot is reliable and remains stable at pilot start up 14 Once the pilot has been adjusted and is reliable the burner should be turned off and the main oil cock should be opened manually 15 The burner should be restarted throug...

Page 42: ... controls When the water falls below the set water level the burner should turn off and restart automatically when the water level is restored to the correct level With some applications a low water cut out is employed this will require a manual reset before the burner turns back on and is not an automatic operation The following general test equipment is required during Start up and Servicing wor...

Page 43: ...Section 11 Service Recommendations ...

Page 44: ...lly Service Tech Check with combustion check Combustion air Weekly Operator All sources remain clean and open Ignition system Weekly Operator Open limit switch carry out aural and visual checks Check flame signal strength Weekly Operator Monitor UV signal via the MM display and log data Pilot fuel valves Weekly Operator Perform leakage tests refer to the valve manufacturers instructions UV scanner...

Page 45: ...k Annually Service Tech Test low fire interlock in accordance with manufacturers instructions Purge position interlock Annually Service Tech Test purge position interlock in accordance with manufacturers instructions Purge air switch Annually Service Tech Test purge air switch interlock in accordance with manufacturers instructions Leakage tests Annually Service Tech Perform leakage test on pilot ...

Page 46: ...ed Service Tech See pilot turndown test All routine checks should be carried out along with any local codes or site specific maintenance requirements Please refer to heat exchanger manufacturer s instructions for any further exchanger specific procedures for fluid levels heat and pressure tests All service works should be carried out by a fully trained technician to a safe and competent level All ...

Page 47: ...Section 12 General Burner Servicing Procedure ...

Page 48: ... pressure The gas head injection gap can be increased or decreased to improve gas to air mixing please see gas manifold section The service technician should refer to the commission report if he she is unsure of the correct gap setting of the burner Oil Burners LC9 and 15 burners The LC9 and LC15 Limpsfield oil burners are designed to have the oil pressurized to 300 psi supplied to the oil nozzle ...

Page 49: ...the oil pipe work if this is the case ensure that all of the air is expelled from the oil pipe work before re firing the burner The burners are fitted with a check valve in the return pipe work this should be checked for debris and correct operation Always use calibrated U tubes pressure gauges when commissioning on gas you will also require a smoke tester when commissioning on the burner on oil O...

Page 50: ...replace as required 8 Clean any deposits from the diffuser 9 Clean and check the pilot assembly as required LC21 and 36 only 10 Check ignition electrode for cracks or damage 11 Check the blast tube for heat damage especially the combustion chamber end 12 Reset ignition and pilot as shown in sections 3 5 13 Check air damper for excessive play on connection to servo motor 14 Ensure gas manifold o ri...

Page 51: ...nformation if in doubt please contact Limpsfield s technical department Gas Control Train Maintenance All electrical connections on the gas control train should be checked to ensure connections are tight Any filters before the gas train should be checked and cleaned as needed to ensure correct operation When burner is firing gas inlet and outlet pressure should be checked to the commissioned combu...

Page 52: ...Section 13 Fault Finding ...

Page 53: ...8 FD Combustion fan motor faulty replace if required 9 Flame Safeguard locked out reset and determine reason for lockout Burner starts but locks out after 10 seconds 1 Air pressure switch or air sensor faulty replace as required 2 Wiring to air pressure switch faulty check and rewire if required Burner fails to light at pilot stage 1 Pilot gas is not tuned on turn gas isolation cock on 2 Gas pilot...

Page 54: ... on main gas isolation cocks 2 Oil solenoid valves faulty check valves open when energized 3 Oil valves faulty check wiring connections 4 Check fuel supply to burner is ok Oil supply from local tank could be isolated or tank could be empty 5 Check oil pump is rotating correctly in the correct direction Check motor wiring connections check motor windings for integrity check motor to pump coupling 6...

Page 55: ...uld read in between 3 to 4 without making any smoke Re adjust oil air ratios to correct white smoky condition 2 Oil flame is over aired check for low oil pressure due to incorrectly adjusted oil pressure regulator adjust as required 3 Oil flame is over aired check for blocked oil filter clean or replace as required All information shown in the table above is typical information if in doubt please ...

Page 56: ...Section 14 Commissioning Report ...

Page 57: ...hannel 3 channel 4 channel 5 channel 6 O2 Vol CO2 Vol CO ppmvd NO ppmvd SO2 ppmvd Smoke number T exhaust oF Pwindbox WG Pfurnace WG Pstack WG Pfuel supply Pfuel return oil only Spillback psi psi High 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Low FGR start Golden start Comments Engineer Customer ...