The types of appliances covered by HTR1 training and asessment includes:

• Gas fires
• Wall heaters
• Convector heaters
• Stoves, which may be open, balanced or fan assisted
• Flueless gas fires (with and without catalytic converters)
• Greenhouse heaters

The Gas Fire and Wall Heater (HTR1) course is not fuel specific and the range of appliances may be either Natural Gas (NG) or Liquefied Petroleum Gas (LPG).

Prior to taking HTR1, gas engineers will need to hold a valid appropriate core gas safety assessment and CPA1, or equivalent Gas Services N/SVQ or QCF qualification. The core assessment is determined by the fuel supplied and the type of dwelling where the appliance is fitted, for example:

• NG wall heater or gas fire fitted in a house, flat or bungalow = CCN1
• LPG wall heater or gas fire fitted in a house, flat or bungalow = CCLP1 (PD)
• LPG gas fire fitted in a Residential Park Home = CCLP1 (RPH)

HTR1 is designed to assess the competence of a gas engineer to install, exchange, commission, disconnect, service, carry out repairs and attend to breakdown of appliances. However, as with all ACS assessments, HTR1 will only assess an engineer’s competence in matters of gas safety, it will not assess other key skills such as building works or electrical installation etc.

Due to the range of appliances and work activity covered by HTR1, during assessment gas engineers must be able to correctly identify the appliance type, apply the guidance given in the manufactures instructions and appropriate British Standard, and ensure that the appliance is safe to use.

Typical HTR1 training, for an installer undertaking this module for the first time, will include:

• Installing and commission an appliance
• Attending to breakdown and diagnosing gas safety faults
• Carrying out a service and identifying any installation or component defects

In addition to the practical HTR1 assessment, a number of underpinning knowledge questions covering the requirements of British Standards (BS) 5871 parts 1 – 4 must be answered correctly. Gas engineers undertaking HTR1 as a reassessment are not required to carry out the installation element and will answer fewer knowledge questions.

Gas Fire and Wall Heater Safety (HTR1) training and assessment is available as part of Logic4training’s CCN1 and appliances package, or as stand alone unit.

The MET1 Gas Meter Safety Assessment is designed to test gas safety competence if an installer’s domestic gas meter work includes:

• Installing from new
• Exchanging from existing
• Permanently removing and commissioning/decommissioning.

MET1 assessment is not required simply to connect a gas meter or to make minor alterations during a domestic system installation.

MET1 (gas meter safety) training covers primary and secondary meters, up to six cubic metres per hour capacity, with a low supply pressure of less than 75 mbar. Operatives installing meters with a higher supply pressure, between 75 mbar – 2 bar, will additionally require the REGT1 assessment.

Candidates must hold one of the following core qualifications as a pre-requisite for taking MET1: CCN1, COCN1 or CCCN1. Non-domestic engineers can undertake MET1, without the need for CCN1, but only if they encounter domestic sized appliances within non-domestic premises.

Gas meter training covers the following topics:

• Gas Safety Legislation
• Installation of pipework and fittings
• Test for tightness
• Checking and/or setting meter regulations
• Identification of unsafe situations
• The Operation and positioning of emergency controls
• Emergency notices and warning labels
• The operation and checking of gas safety devices and controls
• Flue testing
• Installation of open, balanced and fan assisted flue assemblies
• Gas Emergency Actions and Procedures
• Characteristics of combustion
• Ventilation
• Re-establish existing gas supply and re-light appliances.

The MET1 course does not include training on electrical or telecommunication components, and therefore smart meters, or the following:

• Meter reading
• Pre‑payment mechanisms
• Meter box installation
• Construction of meter compartments or housings
• Pipework installation
• Installation or exchange of emergency/meter controls to service pipework
• Service valves or their operation
• Meter removal from site and subsequent disposal
• Testing by Office of Gas Supply Technical Directorate or by OFGEM Technical Directorate and theft of gas.

Contractors have historically included MET1 as part of the training package for its operatives, but they are frequently finding they do not need this module. Gas providers are currently not undertaking major meter replacement programmes, so the demand for this type of work is decreasing. In the rare instance where there is a need to move a meter to a new location, the meter owner would need to be consulted to arrange the work and grant their permission to break and re-seal the governor.

Gas Meter Safety training and assessment (MET1) is available from Logic4training as a stand-alone appliance module.

Individual appliance modules, CEN1 and WAT1, have been replaced with CENWAT, which became effective from 1^st April 2011.

The types of domestic appliances covered by CENWAT (Central Heating and Hot Water) training includes:

• Open and balanced flue (natural draught and fan assisted)
• Central heating & hot water boilers
• Circulators
• Combination boilers
• Storage water heaters
• Instantaneous water heaters with a heat input equal to or less than 70kW.

The CENWAT assessment is not fuel specific and the range of appliances covered may be supplied by either Natural Gas (NG) or Liquefied Petroleum Gas (LPG).

Prior to taking CENWAT, gas engineers will need to hold an appropriate valid ACS core gas safety assessment and CPA1.

CENWAT is designed to assess the competence of a gas engineer to install, exchange, commission, disconnect, service, carry out repair and attend to breakdown of appliances. However, as with all ACS assessments CENWAT will only assess an engineer’s competence in matters of gas safety, it will not assess other associated key skills such as plumbing or the electrical installation etc.

Appliances fitted in commercial premises

Many domestic gas boilers and water heaters covered by CENWAT are fitted in commercial premises; in this case an engineer holding an appropriate commercial ACS core may undertake CENWAT without holding CCN1 or CCLP1. The Gas Safe Register will recognise this combination of assessments as proof of competence to work on these appliances, but will not issue a license card for domestic gas boilers or water heaters.

Examples where a domestic appliance may be fitted in commercial premises with the appropriate ACS core assessment could be as follows.

• 30kW NG System boiler fitted in a plant room (COCN1)
• 35kW NG Combination boiler fitted in catering kitchen (CCCN1)
• 24kW LPG water heater fitted in a commercial laundry (CCLNG1 + CoNGLP1 (PD)

The Assessment

A typical practical CENWAT assessment for an engineer carrying this out for the first time will include:

• Completing the installation and commissioning of a gas boiler
• Identifying gas safety components
• Installation faults and servicing in accordance with the manufactures instructions
• Operational and performance check of an instantaneous water heater, including temperature rise and flow rate.

Gas engineers whose CEN1 and WAT1 assessments are expiring may undertake CENWAT as a reassessment, which omits the installation element and requires fewer knowledge questions to be answered.

CENWAT training forms part of Logic4training’s Gas Safety (CCN1) and appliances course, or is available as a stand-alone appliance module.

Combustion Performance Analysis (CPA1) training and assessment is now compulsory for all Gas Safe Registered engineers who carry out work on Central Heating Boilers and Water Heaters (CENWAT) or Gas Fires and Space Heaters (HTR1).

Gas engineers may be required to undertake combustion performance analysis (CPA1) when carrying out any of the following types of work

• Commissioning a new  installation (where required by the appliance manufacturer)
• Re-commissioning after servicing or after replacement of parts
• When determining service requirements

Combustion Performance Analysis (CPA1) training is based on the requirements of British Standard (BS) 7967 Parts 1 -4, the assessment is designed to test an engineer’s competence to undertake and interpret the results of a combustion performance analysis, obtained across a range of domestic gas appliances including; flueless, open flued & room sealed appliances.

Using a portable electronic combustion analyser

A combustion analyser takes a sample of the combustion products and measures the levels of CO, CO₂, CO/CO₂ ratio, oxygen and the flue gas temperature. For the majority of domestic appliances it is the CO/CO₂ ratio that is used to determine whether combustion is correct or the appliance requires attention e.g. servicing.

Possible reasons for poor combustion include:

• Lack of maintenance e.g. blocked primary air port or heat exchanger, dirt or debris on fan or burner
• Defective or damaged gas or combustion components e.g. split burner, distorted heat exchanger etc.
• Incorrect gas rate or burner pressure

Where the cause of the poor combustion analysis cannot be rectified by inspection, servicing, cleaning or adjusting, the appliance manufacturer should be consulted and the appliance dealt with in accordance with the Gas Industry Unsafe Situations Procedure (GSUSP).

How to obtain a sample of the products of combustion

Prior to obtaining a sample of the products of combustion the appliance should normally be allowed to operate for at least 10 minutes, this is to ensure the appliance is at normal operating temperature and levels of CO and CO₂ produced have stabilised. During this time the analyser must be prepared for use by turning on and purging the sampling probe and hose, this normally takes 1-2 minutes.

Note; some boiler manufactures will require the appliance to be put into ‘service mode’ or operate at maximum gas rate prior to obtaining a sample.

The sample must be obtained from within the combustion stream with the sampling probe normally inserted 200mm in to the flue, this ensures the combustion products are well mixed and an accurate sample is taken.  For open flued appliances; the most convenient sampling point is normally via the draught diverter, with room sealed appliances, there are two options how to obtain a sample;

• Where the appliance is fan assisted and incorporates an integral flue gas sampling point (normally as part of the flue elbow) the sample should be taken from that point.
• Where there is no sample point provided and terminal is accessible the analyser probe can be inserted in the flue discharge duct in the flue terminal

Where a room sealed appliance does not incorporate an integral flue gas sampling point and the terminal is not easily accessible e.g. in a high rise building, it will not be possible to obtain a sample of the combustion products.

CPA1 training and assessment is included within the CCN1 course, for more information about our range of gas courses, click here.

Logic4trade sells flue gas analysers, necessary for combustion performance analysis. Click here to find out more.