DOMESTIC & LIGHT COMMERCIAL SERVICING AND COMMISSIONING

Transcription

1 DOMESTIC & LIGHT COMMERCIAL SERVICING AND COMMISSIONING Requirements for Oil Fired Systems Pressure Jet Appliances Foreword This publication is one of a number of technical manuals provided by OFTEC to assist those involved in oil delivery, installation &/or maintenance of equipment to understand the practices, principles and safety requirements of their work. OFTEC technical manuals can also be used as a reference to support technicians during OFTEC training & assessment and assist them out in the field. The Service and Commissioning Technician undertakes an important role within the industry and both manufacturers and users of oil fired equipment have come to depend upon them for a high level of competence and professionalism. This role includes inspection of equipment to determine compliance with Building Regulations and through servicing and repair ensures that the installed equipment is safe and operating at peak efficiency and performance. Scope OFTEC Technical Book 2 provides generic information about oil, the combustion process, single stage pressure jet burners and related equipment used for domestic & light commercial space heating, hot water and cooking purpose using liquid fuels to BS 2869 (Class C2 kerosene and Class D gas oil), bio-liquids to EN and bio-liquid/mineral fuel blends to OPS 24. It should be noted that this publication is not a compendium of the individual requirements for all modern equipment and should be read in conjunction with equipment manufacturer s literature. This publication has been compiled into the following 10 sections: Section 1 The Technician The role of the Service and Commissioning Technician including guidance on how to implement a positive and professional working manner in order to meet customer expectations. Section 2 Oil Information regarding oil, the refining process and typical fuel characteristics. Section 3 Oil Fired Pressure Jet Appliances Basic operating principles of oil fired heating and cooking appliance that utilise pressure jet burners Edition Introduction Page I

2 Section 4 Pressure Jet Burners Detailed information relating to the operating principles of pressure jet burners. Included are details on the various component parts and how they inter-relate to one another, plus, burner inspection and maintenance procedures. Section 5 Combustion The constituents of fuel and the basic principle of achieving good combustion, what influences combustion and why and how flue gas analysis takes place to ensure that appliances are operating at peak efficiency and performance. Section 6 Service and Commissioning Procedure Detailed information relating to the procedures that technicians should follow when commissioning an installation for the first time or performing planned maintenance. Section 7 OFTEC Procedures Procedures that technicians should implement into their everyday work in order to meet legislative requirements in the production and distribution of information relating to work carried out. Section 8 Fault Finding General guidance on finding the cause of malfunctioning pressure jet appliance installations. Section 9 Acknowledgements Section 10 Blank Pages Intentionally blank pages for technicians to record information. Copyright The Copyright of this publication rests in OFTEC. All rights reserved. This document and its information is supplied without liability for errors or omission and no part may be reproduced, used or disclosed except as authorised by Contract or other written permission. Page II Introduction 2010 Edition

3 OFTEC The Oil Firing Technical Association (OFTEC) was formed in April 1991 with the aim of improving standards within the oil firing industry and to make available information, tools, equipment and products to enable all concerned to carry out their functions compliantly. The Members of the Association are made up of representatives from oil companies, oil distributors, manufacturers of equipment and training & assessment centres utilised by the oil firing industry in the United Kingdom, Channel Islands, Isle of Man and the Republic of Ireland. In addition to OFTEC s activity as a trade association, OFTEC operates a Competent Persons Register. This allows technicians that undergo training and assessment in the installation of different heating technologies to apply for registration in order to self-certify their installation work, as required by some regional Building Regulations. OFTEC currently offers registration with regard to oil, heat pumps, solar thermal, unvented hot water, and electrical installation work. See for further developments in the registration area. Through the OFTEC trade association, an important aspect of work is the testing, approval and certification of oil firing equipment. A scheme for this is operated under the name of OFCERT TM. OFCERT TM is an integral part of OFTEC s mission to promote excellence in oil fired heating and cooking. Specifiers and users of OFCERT TM licensed oil firing equipment can be sure that it exceeds the latest standards of manufacturing and legislation. Equally, because OFCERT TM is the dedicated testing and certification scheme for oil firing equipment, it gives added prestige to the high standards of manufacture within the industry. OFTEC Member Independent Test Houses carry out testing to OFCERT TM requirements. Each Test House must have UKAS or ILAB approved test procedures and they are consulted with regard to the development of OFCERT TM Standards. Manufacturers can apply for OFCERT TM approval for their own test facilities as Auxiliary Test Facilities, providing they meet stringent criteria including UKAS or ILAB approval for their operations. Testing at Auxiliary Test Houses is usually required to be supervised by an appropriate Main Test House. Main Test Houses are first class independent or government laboratories. A full list of current test houses can be found in the OFTEC Equipment Directory/Specifiers Guide. The OFTEC Equipment Directory/Specifiers Guide is a valuable resource for specifiers and users of oil firing equipment. Updated regularly, the Directory is available online and contains comprehensive details of oil firing and associated equipment. It also shows which products have obtained OFCERT TM licences, along with details of relevant European Standards and Directives. Copies of the relevant OFTEC Standards together with application forms are available to order from OFTEC. OFCERT TM licences are awarded to equipment that has satisfied the requirements of an OFTEC Standard and is produced to a Quality Assurance scheme incorporating that standard. The scheme is operated under the overall supervision of the OFCERT TM Scheme Committee. This is one of many OFTEC publications. For a complete listing please visit the publications section at Edition Introduction Page III

4 TECHNICAL UPDATES Due to developments in technology and changes in building regulations, OFTEC will from time to time issue updates to this publication to maintain its accuracy. OFTEC technicians can obtain updates as free of charge downloads from the OFTEC website as a benefit of registration. Printed copies can be obtained from OFTEC on request and a charge may be levied for this service. So that latest information is held and can be referred to, it is recommended that registered technicians take advantage of free technical updates, which should be printed and inserted into this publication. The table below has been provided to record updates to this publication and may be viewed as part of an OFTEC inspection as evidence that a technician is aware of latest changes in industry. The first line of the table is completed as an example of the information required. Update Reference Date of Update Page Reference AMD /09/2010 Section 4, Page 22 AMD /01/2011 Section 6, Page 27 AMD /03/2013 Section 6, Pages 6 to 7 AMD /03/2013 Section 6, Page 20 AMD /03/2013 Section 6, Page 22 AMD /03/2013 Section 6, Page 25 AMD /03/2013 Section 7, Pages 5 to 6 AMD /03/2013 Section 7, Pages 9 to 12 & 14 AMD /03/2013 Contents, Pages X to XI & XIII AMD /03/2013 Section 8, Page 5 AMD /09/2013 Section 7, Pages 5 to 6 AMD /01/2014 Section 5, Page 18 AMD /01/2014 Section 6, Page 24 AMD /06/2014 Section 6, Page 19 12/01/2015 Various (BS Update) Page IV Introduction 2010 Edition Version 8

5 4.3.7 Calculating Nozzle Size and throughput Pressures Inspection and Maintenance Set-up Procedure Maintenance Procedure SECTION 5 COMBUSTION 5.1 Fuel Properties Constituents of Fuels Calorific Value Fuel Suitability Principles of Combustion Requirements for Combustion Composition of Air Fuel Oil Flames Physical Requirements for Oil Burning Oil Atomising and Vaporisation Combustion Air Supply and Air-Oil Mixing Heat Source Oil Burning Summary Excess Combustion Air Excess Air Requirement Excess Air Measurement Why Excess Combustion Air must be Carefully Controlled Incomplete Combustion Smoke Soot Carbon Monoxide Efficiency Loss Common Causes of Poor Combustion in Oil Flames for Pressure Jet Burners Combustion Analysis Reasons for Combustion Analysis Combustion Efficiency Readings Types of Test Equipment Oil Pressure and Vacuum Gauges and Test Manifolds Smoke Tester Draught Gauge Electronic Test Equipment Maintenance and Calibration of Test Equipment Edition Contents Page VII

6 Blank Page SECTION 6 COMMISSIONING AND SERVICE PROCEDURE 6.1 Pre-Commissioning Checks System Preparation Required Appliance Heat Output Rating (CD/11 Schedule Item A1) Commissioning General Commissioning Checks Servicing the Appliance Requirements Planned Procedure Safety Safe Electrical Isolation Cleanliness Observation The OFTEC Service and Commissioning Schedule and Report CD/ Service Details Oil Storage (CD/11 Schedule Item 1) Oil Storage Tank and Supports (CD/11 Schedule Item 1.1) Tank Location (CD/11 Schedule Item 1.2) Water Contamination of Stored Fuel (CD/11 Schedule Item 1.3) Oil Contents Gauges (CD/11 Schedule Item 1.4) Filling Systems (CD/11 Schedule Item 1.5) Vent Systems (CD/11 Schedule Item 1.6) Overfill Alarms (CD/11 Schedule Item 1.7) Oil Supply System (CD/11 Schedule Item 2) Oil Supply Systems (CD/11 Schedule Item 2.1) Oil Line Filter (CD/11 Schedule Item 2.2) Fire Valves (CD/11 Schedule Item 2.3) Mains Equipotential Bonding Air Supply (CD/11 Schedule Item 3) Combustion Air Supply (CD/11 Schedule Item 3.1) Ventilation Air Supply (CD/11 Schedule Item 3.2) 'Make up' Air Supplies (CD/11 Schedule Item 3.3) Flues and Chimneys (CD/11 Schedule Item 4) Inspection (CD/11 Schedule Item 4.1) Page VIII Contents 2010 Edition

7 Diagram 28 Atomisation... 8 Diagram 29 Pressure Jet Oil Burner... 8 Diagram 30 Simplified Schematic of the Combustion Processes Pressure Jet Burning... 9 Diagram 31 Effect of Increased Excess Air on the Carbon Dioxide Diagram 32 and Oxygen Contents of Flue Gases for Pressure Jet Burners Excess Air - Relationship with Smoke Production and Efficiency for Pressure Jet Burners Diagram 33 Efficiency Loss Diagram 34 Gross Flue Loss as a Percentage of Heat Input for Kerosene Diagram 35 Pressure and Vacuum Gauges Diagram 36 Smoke Tester Diagram 37 Draught Gauge Diagram 38 Flue Gas Analyser with Probe and Remote Printer Diagram 39 Removed as part of update Diagram 40 Removed as part of update Table 6 Typical Combustion Readings Table 7 Gross Flue Loss Chart Corrected for an Ambient Temperature of 15.6 o C (60 o F) SECTION 6 DIAGRAMS AND TABLES Diagram 41 Completed Flue and Hearth Data Plate Table 8 Nozzle Conversion Chart SECTION 7 DIAGRAMS AND TABLES Diagram 42 OFTEC Oil Warning Sticker... 1 Diagram 43 CD/10 Form... 3 Diagram 44 CD/10T Form... 4 Diagram 45 CD/11 Form (Front)... 6 Diagram 46 CD/11 Form (Back)... 7 Diagram 47a CD/12 Form... 9 Diagram 47b CD/14 Form Diagram 48 CD/30 Form Edition Contents Page XIII

8 THE TECHNICIAN 1.1 The Role of the Service and Commissioning Technician Fuel Supply is a Competitive Business The Service & Commissioning Technician, whether employed by an oil distributor or working for an independent company, is the most important interface between the oil firing industry and its customers. There is a great deal of competition in the fuel business, which makes this relationship vitally important. Oil is not the only fuel for home heating. Natural gas, electricity, LPG and solid fuel are also available. The companies supplying these fuels offer attractive inducements to persuade customers to use their products. Oil is supplied by independent distributors who compete with each other and have to provide a good service. The work of the Technician is a vitally important part of that service Why is the Service & Commissioning Technician Important? If your company or the company you represent can offer, the best appliance service techniques in the area, your organisation will attract new business, and your present customers will stay with you. The Service & Commissioning Technician is in an excellent position to contribute a great deal to such good customer relations. Customers often contact Service & Commissioning Technicians for the first time when there is a problem with their heating systems. The manner in which they approach their customer in these circumstances is vitally important. In addition to their professional capability in executing their work, it also requires that they keep in mind the fact that they are the front line representatives of not only their company but also the oil industry. Page 1 Section Edition

9 Schematic of an Oil Refinery Process Diagram Edition Section 2 Page 4

10 2.3 Oil for the Domestic and Industrial Heating Market Oil is an excellent fuel for heating. It contains a great deal of heat per unit volume, it is stable under a range of environmental condition, easily transportable and its flow can be quite simply controlled. Many oil fuels, particularly those used for domestic heating, have extremely low sulphur contents that can help to reduce pollution. With the wide range of atomising and vaporising combustion equipment available, oil can be easily mixed with air to form a combustible mist that will burn cleanly and to a pre-set flame pattern. Mineral oil can be safely stored in suitable, simple containers with minimal decal in fuel properties. Handling is straight forward and the metering of quantities delivered creates no problems. In the rare event of an accident occurring, the spilt fuel may be messy but it is usually not dangerous. Oil is an easy fuel to live with. As a world-traded commodity, oil can suffer from price fluctuations, especially at times of international tension. History shows, however, that high prices caused by such events are rarely permanent and when this applies to a fuel for which most customers have significant storage facilities, the effect of such possible variations on those who manage their stocks properly should not be very noticeable. About 900,000 homes in England, Wales and Scotland, 460,000 homes in Northern Ireland, 500,000 homes in the Irish Republic, and a large number of commercial and industrial concerns use oil as a fuel for heating, steam raising or process work. When modern equipment is installed they enjoy a significant running cost advantage over the users of other fuels. Oil can be a significantly less expensive domestic heating fuel than its competitors as the following diagrams show. The following graphs show the average fuel cost comparison for space and water heating of an average sized three bedroom house, as provided by the October 2014 edition of The Sutherland Tables. They represent the average cost of using a condensing boiler, or appropriate heating system for the particular fuel, for properties that do not have access to the gas mains network. Comparative Domestic Fuels Costs (Source: Sutherland Tables October 2014) Diagram 4a Average cost of space and water heating for an average sized three bedroom house in England, Wales and Scotland using a condensing boiler or heating system available for fuel supply ( ) Solid Fuel Electricity LPG Oil Page 5 Section Edition

11 Comparative Domestic Fuels Costs (Source: Sutherland Tables October 2014) Diagram 4b Average cost of space and water heating for an average sized three bedroom house in Northern Ireland using a condensing boiler or heating system available for fuel supply ( ) Solid Fuel Electricity LPG Oil Comparative Domestic Fuels Costs (Source: Sutherland Tables October 2014) Diagram 4c Average cost of space and water heating for an average sized three bedroom house in the Republic of Ireland using a condensing boiler or heating system available for fuel supply ( ) Solid Fuel Electricity LPG Oil * The figures in diagrams 4a, 4b and 4c cover the period between January 2014 and October * The Sutherland Tables figures compare running costs and do not include capital costs. * LPG running cost figures includes LPG tank rental costs Edition Section 2 Page 6

12 2.4 Oil Characteristics Specifications See OFTEC Technical Book 1 and BS Viscosity Viscosity is a measure of the thickness of a liquid and thus its resistance to flow. It is defined as the force per unit surface required to shear a layer of unit thickness at a unit velocity. More viscous oils are often considered to be thicker Test Methods Although the Redwood scale of viscosity is obsolete, it is still sometimes quoted. The scale was abandoned because of its very poor repeatability and reproducibility, which was a consequence of the rather low test temperature of 38 C. The viscosity test used today is known as the kinematic method. It is based on the measurement of the time taken for a fixed volume of fuel oil to flow under prescribed conditions. It is recorded in Centistokes (cst) which are equivalent to mm 2 /s Centistokes (cst) These units are directly equivalent to the SI unit of mm 2 /s. British Standard 2869 requirements for fuel oils are: Class C 1.5 cst at 40 o C Class D 3.1 cst at 40 o C Class E 8.2 cst at 100 o C Class F 20.0 cst at 100 o C Class G 40.0 cst at 100 o C NOTE: 40 o C 104 o F 100 o C 212 o F The last three classes of oil are not typically used in domestic heating. Page 7 Section Edition

13 Where bio-liquids are produced from used cooking oil, they tend to offer greater lifecycle green house gas savings, as the used cooking oil is considered a waste at the point is converted to a fuel, so the emissions before that point are counted as zero. This compares to many vegetable oils, which have green house gas emissions associated with their cultivation, through the use of fertilisers, for example. FAME for heating purposes should meet the requirements of EN and can either be used as part of a blend with mineral fuels such as kerosene or gas oil, or used in its pure form as a 100% bio-liquid fuel. Fuel must also be produced under strict quality assurance systems to achieve consistent quality and properties of the fuel. The properties of bio-liquids and bio-liquid blends in comparison to mineral fuels such as kerosene are very different. This is an important factor to bear in mind as this means that to change from 100% mineral fuel, such as kerosene, even to a kerosene bio-liquid blend is likely to require formal conversion and re-commissioning of installations and equipment. In basic terms, bio-liquid fuels are thicker, heavier and have different energy content. Additionally, the properties of bio-liquids differ from mineral fuels and react differently to different materials. Materials such as rubber, as found in fuel pumps and as filter seals, are commonly in contact mineral fuels, but may not be compatible with bio-liquids. Pressure jet appliances and installations can be converted to run on bio-liquids with relative ease, but only where the actual properties of the fuel are known. Conversion would commonly require at least the replacement of atomising nozzles, fuel pumps, flexible oil lines, filters/filter seals and re-commissioning of the burner would also be required. Attention should also be paid to suction line sizing as a correctly sized kerosene suction line may require an increase in size for example from 6mm to 8mm or even to 10mm. Bio-liquids are hydroscopic (they absorb water) and should never be introduced to oil storage and supply systems which are contaminated. Contaminated systems should be cleaned before switching over to bio-liquids as the consequences may inevitably be blocked filters and inoperative systems as the bio-liquid picks up water and sludge that may have built up within the system. Bio-liquids should never be introduced to existing oil storage tank installations which do not have secondary containment as the cleaning effect of the fuel may well find weaknesses in existing tanks which lead to leaks. It is recommended that wherever possible and practicable new integrally bunded oil storage tanks suitable for bio-liquids are considered. To help prevent long term storage stagnation it is recommended that smaller tanks are utilised based upon half yearly usage. For bespoke installations where a 100% FAME is being considered as the fuel to be used consideration will have to be made to the use of heated and insulated (and possibly agitated) fuel storage tanks as well as trace heated and insulated supply lines. For specific advice on the availability of bio-liquid new and conversion equipment & components please contact appliance, equipment and burner manufacturers directly Edition Section 2 Page 12

14 2.5 Fuel Oil Contamination The classes of fuel used for most domestic oil heating and cooking in the United Kingdom are kerosene (Class C2) and gas oil (Class D). (See Technical Book 1). Fuel cross-contamination within the oil storage tank can occur in exceptional circumstances, such as a customer inadvertently placing an order for an incorrect grade of fuel for their appliance. The pictures below show varying percentages of kerosene (C2) contaminated with gas oil (D). The subjective photographs below are for indicative purposes, enabling on-site recognition where extreme examples of cross-contamination have occurred. Water in Kerosene Fuel storage should be checked at least annually for the presence of water using water finding paste or taking a sample of fuel and checking for separation. As can be seen from the adjacent photograph, when a sample of fuel is placed in a vessel the mineral fuel will separate and float on top of the water. Large quantities of water within storage tanks can be identified by shining a touch through the inspection cover and observing the presence of puddle-like beads on the bottom of the tank. Page 13 Section Edition

15 EXAMPLE: Flue Gas temperature 200 o C/CO 2 12% = Flue loss 14.8% Flue loss 100% % = 85.2% Gross Combustion Efficiency 85.2% - 3% = 82.2% Estimated Overall Gross Efficiency NOTE: Where flue gas temperature is between figures given on the chart, e.g. 125 o C, take a difference between 100 o C o C for flue loss percentage. Another means of assessing combustion efficiency is to use the chart shown in diagram 31. Typical combustion test readings are given in table 6. These are for guidance and comparison purposes only and manufacturers figures should be referenced for particular appliances. Appliance manufacturer stated efficiencies, as detailed in the Product Characteristics Database (PCDB) for the UK and in the Home-heating Appliance Register of Performance (HARP) database for the Republic of Ireland, are based on gross calorific values Types of Test Equipment Flue gas analysis should only be performed using calibrated electronic test equipment. Manual draught gauges and Smoke Testers should, however, be used for initial testing before electronic equipment is applied to protect the life of the oxygen cell of electronic analysis equipment. NOTE: All test equipment should be regularly calibrated following the equipment manufacturer's specified instructions with due regard to intervals and methodology Edition Section 5 Page 22

16 5.6.4 Oil Pressure and Vacuum Gauges and Test Manifolds The oil pressure gauge is connected to the relevant pressure port on the fuel pump in order to enable adjustments to be made to the pumps performance. The vacuum gauge is connected to the vacuum port on the fuel pump in order to confirm that the suction resistance of the oil supply system is within the parameters laid down by the pump manufacturer. This is ideal for commissioning new installations and when fault finding suspect fuel pumps. They have a circular dial calibrated in psi or bar, they are screwed into the port provided on the fuel pump in place of the blanking off plug. The glycerine filled types provide damped action, longer life and are normally capable of being recalibrated. Test manifolds are used to connect pressure and vacuum gauges to fuel pumps. They also enable the correct venting of fuel pumps and supply lines during maintenance procedures. Pressure and Vacuum Gauges Diagram 35 Shown above: Glycerine filled pressure and (compound) vacuum gauges complete with manifold and high pressure flexible connection hose assembly. Page 23 Section Edition

17 5.6.7 Electronic Test Equipment Combustion analysis should only be performed using calibrated electronic test equipment. Electronic flue gas analysers have various models available and measurements can be taken of flue gas temperature, CO 2/O 2/CO ppm and smoke number. Readings of percentage CO 2/O 2, excess air and combustion efficiency can be obtained. CO is read as parts per million (ppm). This equipment can be set up to monitor all the parameters of the combustion process simultaneously. The advantage of this is that the operator can monitor the display while making adjustments to the burner, speeding up the commissioning and giving a more accurate picture of the performance. One of the advantages of these types of equipment is that a printout of the test results can be left with the customer. Maintenance of this equipment and care in handling it is absolutely vital, including calibration checks to the manufacturer's recommendations. Flue Gas Analyser with Probe and Remote Printer Diagram Edition Section 5 Page 26

18 5.6.8 Maintenance and Calibration of Test Equipment Oil Pressure and Vacuum Gauges Check that the thread and washer are in good condition. Pressure and vacuum gauges are required to be re-calibrated, normally annually, as an inaccurate gauge can cause burners to be incorrectly set up. Glycerine filled gauges normally have the facility to be re-calibrated by the manufacturer. Smoke Tester Lubricate with the appropriate silicone oil. USE ONLY THIS OIL, as other oils may cause staining of the filter paper and hence affect the smoke reading. Check the short length of rubber tubing regularly for deterioration. Draught Gauge No maintenance is required, but should be handled very carefully. If the casing is damaged, check the accuracy of the gauge. If it is impaired, return the gauge to the manufacturer for repair. When in use, position the gauge so that condensation, which will affect the instrument s accuracy, does not collect inside the mechanism or in the sampling tube. Check the sampling tube regularly for any deterioration. Electronic draught gauges should be checked and calibrated regularly. Electronic Flue Gas Analyser The nature of electronic analysers means they drift out of calibration over time. Test equipment should, therefore, be regularly calibrated following the equipment manufacturers specified instructions with due regard to intervals and methodology. Maintaining combustion instruments within calibration is vital to ensure results of combustion analysis are valid and accurate. Current certificates of calibration must be retained for this purpose. When not in use it is important that the analyser is kept in a warm, dry environment - especially overnight. This is to protect the instrument from malfunctioning due to cold weather damage and condensation which can affect the electrochemical sensors inside. If damage is suspected the analyser manufacturer should be contacted for advice. Page 27 Section Edition

19 BLANK PAGE 2010 Edition Section 5 Page 28

20 COMMISSIONING AND SERVICE PROCEDURE OFTEC WOULD RECOMMEND THAT OIL FIRED PRESSURE JET SERVICE AND COMMISSIONING WORKS SHOULD BE CARRIED OUT BY OFTEC REGISTERED TECHNICIANS HOLDING A CURRENT OFT 101 QUALIFICATION NOTE: The information in this section relates to the completion of the OFTEC CD/11 Oil Fired Appliance and System Service Schedule Report Form 6.1 Pre-Commissioning Checks System Preparation Prior to commissioning work taking place, the installer should ensure the following: a) The appliance has in place a dedicated and safe supply of heating oil. The oil tank should contain a sufficient level of heating oil and, where practicable to do so, the oil supply system should be primed with oil. b) Where the appliance serves a wet heating system, the system in its entirety has been thoroughly cleaned & flushed and is filled with water containing a chemical treatment formulation (inhibitor) to control corrosion and the formation of scale and sludge Required Appliance Heat Output Rating (CD/11 Schedule Item A1) Pressure jet boiler models can be commissioned to provide a rated heat output that is within a given range e.g kW as declared by the appliance manufacturer. The manufacturer will provide with the appliance an oil nozzle for the burner that is normally sized to give a mid-range heat output e.g. 20kW, however, this may not best suit the heat load requirement of the system that the appliance serves. To ensure peak performance is achieved and that the heat load requirement of the system is met, it is important that before appliance commission the required heat output is confirmed by the heating system designer/installer and recorded on the CD/11. Adjustments made to increase or decrease the burner heat output rating should be in accordance with the manufacturer s instructions. In all cases the commissioned heat output must be in scope of the appliance manufacturer s designed parameters. Page 1 Section Edition

21 6.2 Commissioning General When an oil-fired installation is first put into use it is essential that its main features be checked for safe and efficient operation and that, in particular, its burner is set up to suit site conditions. Most manufacturers will test fire an appliance before it leaves their factory but this does not mean that the appliance is ready for use without further adjustment. A commissioning technician must check the installation and carry out a combustion efficiency test in order to ensure that operation is up to the high levels expected by the industry and the end users. Many manufacturers' guarantees will probably depend on this having been carried out. If the installation involves two appliances using the same flue and chimney system and the technician is satisfied that this can be operated safely, then it is essential that any testing undertaken involves the use of both appliances at the same time so that the performance of each appliance can be verified when the chimney is fully loaded. This applies to every category of appliance visit for this type of installation during which combustion testing is undertaken. Further information on this is given in sub-section Commissioning Checks Appliances should be commissioned using the correct calibration equipment and in accordance with the manufacturer s commissioning instructions. The commissioning process should consist of the following steps: a) Ensuring that the installation is safe before the appliance is fired. The OFTEC CD/11 report schedule can be used for this purpose (see sections 6.4 to 6.15 in this publication); b) Ensuring that the appliance performs safely once fired; c) Ensuring that the appliance and system controls operate correctly; d) Checking that the user has been provided with an operating manual for the appliance and has been instructed in the use of the appliance, including maintenance and servicing requirements; e) Ensuring that the commissioning report i.e. OFTEC CD/11, is completed and provided to the end user. When testing is undertaken the results must be recorded and left on site. Evidence of results from electronic flue gas analysers should always be in printed format where print facility exists. Results from manual instruments such as smoke, draught, pump pressure, etc. can be manually recorded on the commissioning report. The general advice given in section 6.3 regarding the organisation of servicing operations should be followed Edition Section 6 Page 2

22 6.3 Servicing the Appliance Requirements To maintain the safe and efficient operation of the appliance and its associated equipment, it should be given a regular skilled service at least once a year or as recommended by the appliance manufacturer. This is best achieved by means of an annual service contract. Traditionally, if an appliance is used all the year round, the best times for its bi-annual servicing were autumn and spring or before the start of the heating season in conjunction with other oil fired heating equipment if present. If an appliance is shut down completely during the summer, the service should ideally be as soon as possible after the annual shut down Planned Procedure In order to carry out a service operation in a professional and effective manner it is necessary to work to a previously planned procedure. The OFTEC CD/11 form is designed to assist you in following this procedure. At the same time it must be remembered that any procedure has to be capable of being adapted to meet the needs of individual situations that include non-standard elements. The set procedure should form a framework within which to work and must not become restrictive Safety The prime aim of service operations is the achievement of safety, both for the user of the equipment being serviced and for the service technician. Accidents are caused, they do not just happen and they can be prevented by forethought. OFTEC Technical Book 1 gives a great deal of information on this subject. Plan your approach to each job. Think about the positioning of cleaning equipment and other items such as ladders. Leads to electrical equipment sometimes have to cross areas where access cannot be entirely prevented. The use of warning notices can reduce risk but always consider an alternative approach if this may be safer, even if it would increase the time taken. See OFTEC Technical Book 3 for Regional and Procedural requirements applicable to oil storage and supply services. See OFTEC Technical Book 4 for Regional and Procedural requirements applicable to oil fired appliance installation Safe Electrical Isolation The safe isolation of electrical supplies is vital and for reference the nine steps for the safe isolation of electrical supplies are noted below: Step 1 Step 2 Step 3 Select an approved voltage indicator with fused leads conforming to HSE Guidance Note GS38 To prove correct function of the voltage indicator on an approved proving unit or a known supply Locate means of isolation for installation or circuit to be worked on e.g. main isolator fuse or circuit breaker Page 3 Section Edition

23 Step 4 Step 5 Step 6 Step 7 Check if the installation circuit or fixed equipment to be isolated is in service Isolate the installation or circuit by switching off and with-drawing the fuse(s) Place fuse(s) in a safe place under your sole control or lock off the isolator or circuit breaker, placing the key in a safe place under your sole control Using the voltage indicator verify that the installation circuit or fixed equipment is dead: Phase to Phase (3 phase equipment only) Phase (Live) to Neutral Phase (Live) to Earth Neutral to Earth Step 8 Step 9 Re-check correct function of voltage indicator on the proving unit or on a known supply Fit warning label to main isolator, circuit breaker or fixed equipment indicating personnel are working on the circuit Cleanliness The cleanliness of the service operation must be given considerable thought. The use of protective sheeting on floors is essential. The means of clearing away dust, grease and oil must be carefully thought through and the equipment used must look smart and be in good condition. OFTEC Technical Book 1 outlines how to deal with various type of oil spills. Please refer to this information when dealing with any kind of spill, whether it is contained within the appliance casing or otherwise. The appliance and the area around it must be left clean regardless of the condition it was in before the service work started Observation The most important skill that service and commissioning technicians can develop is the ability to observe and draw conclusions from what they see, for example multiple appliances using the same chimney (attention should be made to the advice in sub-section 6.1.1). This gives invaluable information regarding the way in which appliances are operating, what is required to rectify any faults and what steps must be taken to improve performance The OFTEC Service and Commissioning Schedule and Report CD/11 OFTEC publishes a Service and Commissioning Report pad to aid the technician covering the majority of the items that need attention during an oil fired appliance service. A copy of this is included in sub-section 7.3. A record of works undertaken, parts fitted and combustion analysis shows the condition in which the appliance was left running, as required by BS 5410: Part 1. This is an essential part 2010 Edition Section 6 Page 4

24 of any appliance visit, issue your customer a CD/11 form or equivalent. In the event of any subsequent claim or dispute, it can be the only means of evidence available for works carried out and advice given. NOTE: Registered OFTEC CD/11 forms are available through OFTEC Direct Service Details The following notes give guidance regarding servicing operations. They are laid out in the same order as the items on the OFTEC Service and Commissioning Report. Page 5 Section Edition

25 6.4 Oil Storage (CD/11 Schedule Item 1) Oil Storage Tank and Supports (CD/11 Schedule Item 1.1) Above Ground Tanks Where practicable, visually check the tank, its fittings, and any associated pipework for signs of oil leakage. Where leakage is identified, the customer must be informed and steps must be taken to stop the leak and/or prevent any further escape of oil to the environment. Tank bases and supports should be checked for signs of movement or determination and that the tank is appropriately supported. See OFTEC Technical Book 3. For steel tanks, annually inspect the sides, top, base and all welded seams for signs of corrosion (rust and/or damp patches) or leaks. In particular, look at those parts of the base that are in contact with supports and check there is a damp proof course between the top of the piers and the tank. Advise the customer of any defects. The treatment for corrosion is to remove the rust, treat the bare steel with a corrosion inhibitor and apply two coats of oil resistant paint. If the tank is heavily corroded or flaking, then no attempt should be made to attend to the defect, but a replacement tank should be recommended. For plastic tanks, annually inspect the installation for significant changes in overall geometry (shape and size) paying particular attention to horizontal and vertical lines, such as the top and sides of the tank. The tank should be inspected for any irregular depressions or bulging in the moulding and the material should be checked for whitening, crazing, or cracking. Plastic oil tanks cannot be repaired. Where the integrity of the tank is bought into question following an inspection, a replacement tank should be recommended. Photographic examples of oil storage tanks in generally poor condition can be found in OFTEC Technical Book 3. Observation associated with oil tank inspection can be recorded and relayed to the customer using OFTEC form CD/11. Underground Tanks In recognition of the practical constraints associated with inspecting underground tanks, BS requires owners to be advised of the need to have the integrity of the tank and associated pipework verified at least annually by a specialist contractor. Records of tests carried out must be retained by the owner as evidence and to facilitate delivery of oil Tank Location (CD/11 Schedule Item 1.2) Check that the oil tank is installed to BS 5410: Part 1, and where necessary carry out a risk assessment (TI/133D) to record your findings and advise the customer accordingly (See OFTEC Technical Book 3, OFTEC Procedures). Check that any screening around the tank is self-supporting, and that plants and foliage are kept on the screening and well away from the tank by at least 600mm. Make sure that combustible material is not stored near the tank and if necessary advise that fires should not be lit near it Edition Section 6 Page 6

26 6.4.3 Water Contamination of Stored Fuel (CD/11 Schedule Item 1.3) Where safe and accessible at the time of the service visit, inspect the tank and associated bund for the presence of water. The stored fuel can be checked by dipping the tank with water identification paste on a suitable probe. If water is detected in the tank and/or bund, the customer should be notified so they can make arrangements for its extraction and safe disposal. Water can be removed from tanks by dropping a tube connected to a hand pump down to the bottom of the tank. Water can be drained via a drain valve if fitted replacing the taper plug into the outlet side of the valve using an oil resistant jointing compound. Alternatively, contained and removable water absorbent media such as water hogs or equivalent as available from OFTEC Direct may be utilised for small quantities. Contaminated water removed from the oil storage facility should not be disposed of through surface water drains. All contaminated waste should be disposed of at a suitably licensed waste disposal site. NOTE: A regional waste carriers licence may be required for the transportation of contaminated material. Refer to OFTEC Technical Book 3 for regional environmental contact details. Alternatively, local arrangements can be made to have the contaminated material collected from site and disposed of by a specialist licenced waste collection/disposal company. For further details refer to the OFTEC Directory/Specifiers Guide. NOTE: Water in an oil storage tank can lead to microbiological growth which can block filters and cause appliance combustion problems, especially with biofuels. Where combustion problems are encountered and cannot be resolved contact OFTEC Technical department for a copy of OFTEC Questionnaire T61Q which may help to identify the problem Oil Contents Gauges (CD/11 Schedule Item 1.4) Check sight gauges for correct operation and reasonable accuracy. Check the springloaded isolating valve of a visual gauge. Replace the transparent tube if it is opaque or has been damaged. Make sure that the cap is in place at the top of the tube. Ensure that the top of the sight tube is securely fixed. Non British Standard sight gauges, which do not have a spring loaded auto shut off valve, are not recommended, but where they are encountered they should be left in the off position and the customer notified accordingly on an OFTEC CD/11 form. Replacement gauges should be to OFTEC Standard OFS E103. If an electronic gauge is fitted, check that it is reading correctly and change the battery as recommended by the gauge manufacturer. Any defects should be advised to your client in writing on an OFTEC CD/11 form Filling Systems (CD/11 Schedule Item 1.5) Check fill points for any signs of wear, damage, corrosion and stability of fixing, to identify suitability of use. Where problems are identified these should be reported to the customer as being in need of rectification to facilitate safe delivery. Check that screwed caps are fitted properly in place and held to the tank by a chain. Check that older style loose lids close properly and are fitted with a closure pin or padlock. Page 7 Section Edition

27 NOTE: Tanks with loose lids are not recommended. On extended fill systems check joints for leaks. If an isolation valve is fitted at the filling end check it is not leaking and that the dust cap is fitted with a sound washer. Make sure that any witness hole in the end thread is clear. Air pressure test procedures for oil lines can be found in OFTEC Technical Book Vent Systems (CD/11 Schedule Item 1.6) Check that the vent is clear and that it discharges down into the bund or secondary containment system where there is one. If an extended vent is fitted, operate the flap at the end of the pressure relief pipe and ensure that it is free to move. Place one or two drops of lubricating oil in its hinges. NOTE: New tanks complying with OFTEC Standards OFS T100 and OFS T200 may employ additional measures to help avoid over pressurisation of the tank during filling Overfill Alarms (CD/11 Schedule Item 1.7) Check the operation and condition of any overfill alarms and warning devices fitted to the tank. Replacement alarms should be to OFTEC Standard OFS E Edition Section 6 Page 8

28 6.5 Oil Supply System (CD/11 Schedule Item 2) Oil Supply Systems (CD/11 Schedule Item 2.1) The oil supply pipework, valves, filters and fire valve(s) (see section 6.5.3) should be visually inspected and checked for correct operation. Visual checks should be made for damage and/or leaks. Where leakage problems are found or suspected, the equipment owner should be advised of the need to have any leaks repaired and the supply pipe pressure tested. Air pressure test procedures for oil pipes can be found in sub-section If a de-aeration device is fitted, check that it is appropriate for its location (internal or external, separation from a flue terminal see OFTEC Technical Book 3) and that it is in good condition and that it is venting properly Oil Line Filter (CD/11 Schedule Item 2.2) Annual inspection of all filter media is required as part of routine service visits. It is important to take particular care in re-assembling aluminium alloy filter bodies. Cross threading almost invariably causes damage and consequently leaks, which cannot be stopped. Over tightening may easily cause a fracture and must also be avoided. Where an existing oil filter is unserviceable, it should be replaced using a filter manufactured to OFTEC Technical Standard OFS E104. NOTE: Any used filter elements and absorbents such as rags or towels that come into contact with oil during the filter replacement process are deemed contaminated waste and should be disposed of in line with current legislation. It is important that the appliance/burner manufacturer s specified filtration requirements are met. For further guidance on filter installation and micron rating requirements refer to OFTEC Technical Book 3, Section 2. Replaceable Cartridge/Element Types Annual replacement of disposable filter elements and seals are essential to protect downstream equipment. Mark the date of fitting a new cartridge on the top or body of the filter. Follow the filter manufacturer's instructions as contained within the manufacturer's replacement service kit. Page 9 Section Edition

29 Metal Element Type Annual replacement of disposable filter elements and seals are essential to protect downstream equipment. Mark the date of fitting a new cartridge on the top or body of the filter Follow the filter manufacturer's instructions as contained within the manufacturer's replacement service kit. Where manufacturer s instructions are no longer available the following procedure is recommended: Isolate the oil supply. Position an oil proof tray beneath the filter bowl to safely contain any drips. Ensuring sorbent materials are ready to hand, unscrew bowl-retaining screw and lower the bowl. Remove filter element from the housing, wash in clean oil, inspect condition and, if satisfactory, replace carefully. Fit new seals to the unit and reassemble bowl to the upper section of the filter. Turn on the oil supply, check that the bowl is oil tight and bleed off any air through the bleed screws on the upper section. Air Venting Air trapped in the top of the filter can seriously impair the performance of the burner by restricting oil flow and must therefore be removed. Most filters have vents on the inlet and the outlet side. Integrally combined filter and sight gauge units normally require opening of sight tube valve (as if to read level) to vent new filter Fire Valves (CD/11 Schedule Item 2.3) Remote Acting Phial and Capillary Visually inspect the valve for signs of damage and/or oil leakage at joints with the oil supply pipe. The sensor capillary should be checked throughout its length for any kinks or damage and to ensure that it is adequately supported and protected. The correct operation of the valve should be observed using electronic test equipment. Manufacturers advice should be taken regarding the maximum acceptable valve activation temperature. Due to the inherent frequency of risk of exposure to scalding open to technicians, OFTEC can no longer support the once common use of boiling water being used as a test medium to prove the operation of fire valves. Automatic fire valve field test equipment is available for this purpose. For further advice on field testing methodologies please refer to manufacturers instructions. For guidance on the installation of fire valves refer to OFTEC Technical Book 3, Section Edition Section 6 Page 10

30 Dead-weight/Fusible Link Type Historically used in non domestic installations, check the cable for freedom of movement over the pulleys, remove any kinks in the wire. Release the cable to allow the valve to close and check that it does so correctly (the dead-weight) must be able to swing through its prescribed arc. Check the types, which have a gland around the spindle of the actuating valve, for leaks. If a leak is found the valve should be replaced with a glandless type to British Standard 799: Part 2. See OFTEC Technical Book 3, Section 4. Fusible Pin or Wheel Type This type of fire valve is not recommended for use as the sole means of fire protection for any oil fired appliance installation as per British Standard 5410: Part 1. The reason for this is that British Standard 5410: Part 1 calls for testing of the operation of the fire valve, which with this design would require the application of heat/flame to the fusible part which would in essence destroy this part of the valve. British Standard 5410: Part 1 also calls for fire protection valves to be able to remotely sense fire (and/or temperature rise above appliance ambient) and isolate the fuel supply before it enters the building for internally installed appliances, or at least 1m away from externally installed appliances. For further information regarding fire valves refer to OFTEC Technical Book 3, Section Mains Equipotential Bonding Oil supply pipes should be provided with a main protective bonding conductor in accordance with BS See OFTEC Technical Book 3, Section 2. Page 11 Section Edition

31 CD/30 Form (Oil Condensing Boiler Installation Assessment Form) Diagram THE AVENUE CHURCHFORD A.N OTHER OIL SERVICES C/23456 N/01643/105E/600/101/ N/A N/A 1100 ASSESSMENT SCORE T EXCEEDS 1000 N/A 1100 A.N. OTHER INSTALLER Anthony Other 03/07/ Edition Section 7 Page 13