Glossary- System Control Engineering
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A AGA | Appliance | Authorized Installer | Auto-ignition Temperature | Automatic ignition
B Bleed line | Burner - Atmospheric | Burner - Automatic | Burner - Forced Draught | Burner - Induced draught | Burner - Multi-fuel | Burner - Multi-fuel alternative | Burner - Mutli-fuel simultaneous | Burner - Part automatic | Burner off cycle | Burner unit
C Closed position indicator switch | Combination gas control | Combustion product | Critical time | Cross lighting
D Damper | Direct-fired air heater | Direct-fired ovenheater | Double block and vent | Draught diverter
E Electronic flame safeguard | Excess air
F Fail-safe | Flame abnormality | Flame detector | Flame establishment period | Flame failure response time | Flame lift | Flame proving period | Flame safeguard | Flame safeguard system | Flue | Flue - Common | Flue - Natural Draught | Flue - Open | Flue - Secondary | Flue - Slip Joint | Flue gases | Flue system | Flue terminal | Forced or induced draught combustion system
G Gas consumption | Gas pressure regulator | Gas tight | Gas/air ratio control
H High gas pressure detector | Hot water boiler
I Ignition temperatureor | In service | Indoor flueless appliance | Injector | Interlock boiler | Intermittent pilot | Interrupted pilot | IP Rating
L Leakage detection system | Light back | Limit device | Liquefied petroleum gas (LP gas) | Liquefied petroleum gas (LP gas) | Lockout | Low-gas-pressure detector | Lower explosive limit (LEL)
M Manual ignition | Mixing blower | Mixing tube | Modification
N Natural draught | Natural gas (NG) | No-flow | Nominal gas consumption | Non-return valve
O Open flued appliance | Open position indicator switch | Operating pressure | Opso Regulator | Over-pressure protection system | Over-temperature cut-out device
P Parts Per Million (PPM) | Permanent pilot | Pilot | Position indicator switch | Position-proving system | Pressure | Process after-burner | Programmable electronic system (PES) | Programming flame safeguard | Proof-of-closure switch | Protected pilot | Purge (or purging) | Purge volume
R Rated working pressure | Relief device
S Safe start check | Safety shut off system | Safety shut off system, double block and vent | Safety shut off valve | Safety shutdown | Set pressure | Simulated natural gas (SNG) | Single Phase | Solenoid Valve | Start gas | Steam boiler | Stoichiometric combustion | Supervised burner
T Temperature limit device | Tempered liquefied petroleum gas (TLP) | Test firing valve | Thermocouple | Thermostat | Town gas (TG) | Transformer | Type A appliance | Type B appliance
V Valve | Valve train | Vent line | Vent valve, double block and vent safety shut off system

 

 

 
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A

AGA Related Phrases :
Definition : The AGA (Australian Gas Association) (http://www.aga.asn.au/) provides accredited product certfication serviceswith respect to the gas, electrical and plumbing sectors within Australia. It also provides additional certification services that are accepted by the relevant government/industry regulators.

 

 
back to top  Appliance

 

Related Phrases :
Definition : An assembly, part of which uses gas to produce flame, heat, light, power or special atmosphere.

 

 
back to top  Authorized Installer

 

Related Phrases :
Definition : A person appointed, licensed, authorized or otherwise permitted to carry out gasfitting work.

 

 
back to top  Auto-ignition Temperature

 

Related Phrases :
Definition : The lowest temperature at which the rate of self-heating of a gas-air mixture exceeds the rate of heat loss to the surroundings, thus causing the mixture to ignite.

 

 
back to top  Automatic ignition

 

Related Phrases :
Definition : The lighting of gas at a burner without a manual operation whenever gas flows from the burner.

 

 

 
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B

Bleed line Related Phrases :
Definition : A small diameter pipe or tube that conveys gas to a safe place from a gas component that discharges small rates of gas as part of its normal operation.

 

 
back to top  Burner - Atmospheric

 

Related Phrases :
Definition : A system where all of the air for combustion is produced by the inspirating effect of the gas or the natural draught in the combustion chamber or combination of the two without mechanical assistance.

 

 
back to top  Burner - Automatic

 

Related Phrases :
Definition : A burner system that, on starting, follows a self-acting sequence that has been manually or automatically initiated, to provide gas and ignition to the burner without any intermediate manual operation.

 

 
back to top  Burner - Forced Draught

 

Related Phrases :
Definition : A system where all of the air, oxygen or a mixture of the two used for combustion is provided under pressure.

 

 
back to top  Burner - Induced draught

 

Related Phrases :
Definition : A system where all or part of the air for combustion is introduced by providing suction in the combustion chamber by mechanical means.

 

 
back to top  Burner - Multi-fuel

 

Related Phrases :
Definition : A burner that can use more than one fuel.

 

 
back to top  Burner - Multi-fuel alternative

 

Related Phrases :
Definition : A multi-fuel burner that can use only one fuel at a time.

 

 
back to top  Burner - Mutli-fuel simultaneous

 

Related Phrases :
Definition : A multi-fuel burner that can use more than one fuel at a time.

 

 
back to top  Burner - Part automatic

 

Related Phrases :
Definition : A burner system that includes any self-acting operation.

 

 
back to top  Burner off cycle

 

Related Phrases :
Definition : A normal cessation of operation occurring when a pre-determined operation condition is reached and the operation of the burner to provide the application of heat is no longer required. The equipment is placed into a safe stand-by condition ready to restart on demand; or A shut down to a safe stand-by condition in response to an incorrect condition signal resulting from a fault that is unlikely to be hazardous or is likely to be self rectifying so that normal restarting is permissible when the fault has cleared.

 

 
back to top  Burner unit

 

Related Phrases :
Definition : A number of burners, fed from the same manifold, controlled together, having one supervised ignition source and performing as a single burner.

 

 

 
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C

Closed position indicator switch Related Phrases :
Definition : A switch which indicates closed when the valve is within 1 mm of the closed position or has reduced the flow to 10% or less of the equivalent fully open flow for a given pressure differential.

 

 
back to top  Combination gas control

 

Related Phrases :
Definition : An assembly of two or more different control functions in a single body.

 

 
back to top  Combustion product

 

Related Phrases :
Definition : Constituents resulting from the combustion of a fuel with air, oxygen or mixture of the two, including the inerts associated with the fuel and the air but excluding any other diluent or contaminant.

 

 
back to top  Critical time

 

Related Phrases :
Definition : The time required to build up a pocket or concentration of unignited gas of such quantity and proportions that, if ignited, the pressure of the resultant explosion could equal the permissible safe internal pressure of the appliance.

 

 
back to top  Cross lighting

 

Related Phrases :
Definition : Lighting of one burner from another either directly or by means of an intermediate flame.

 

 

 
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D

Damper Related Phrases :
Definition : An adjustable device for controlling (a) air flow in a forced or induced draught air system;(b) the flow of flue products in a flue system; (c) the recirculation of air, flue gases or process gases; or (d) the flow of any other fluids.

 

 
back to top  Direct-fired air heater

 

Related Phrases :
Definition : An appliance for heating a forced air stream where the combustion products are released with the heated air.

 

 
back to top  Direct-fired ovenheater

 

Related Phrases :
Definition : An oven in which the combustion products flow through the oven compartment.

 

 
back to top  Double block and vent

 

Related Phrases :
Definition : See 'Safety shut off system double block and vent'.

 

 
back to top  Draught diverter

 

Related Phrases :
Definition : A device, without moving parts, fitted in the flue of an appliance for isolating the combustion system from the effects of pressure changes in the secondary flue.

 

 

 
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E

Electronic flame safeguard Related Phrases :
Definition : A flame safeguard utilising electronic components to perform its function.

 

 
back to top  Excess air

 

Related Phrases :
Definition : Air in excess of that required for complete combustion that is mixed unchanged with the combustion products, in the combustion chamber.

 

 

 
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F

Fail-safe Related Phrases :
Definition : A feature that ensures absence or malfunction of any critical control or safety component, system, signal or function will not result in an unsafe condition.

 

 
back to top  Flame abnormality

 

Related Phrases :
Definition : A flame condition that results in flame lift, floating, light back, appreciable yellow tipping, carbon deposition or objectionable odour.

 

 
back to top  Flame detector

 

Related Phrases :
Definition : A device that is sensitive to flame properties and initiates a signal when flame is detected.

 

 
back to top  Flame establishment period

 

Related Phrases :
Definition : The period that begins when the fuel valve is energized and ends when the flame safeguard system is first required to supervise that flame.

 

 
back to top  Flame failure response time

 

Related Phrases :
Definition : The time taken for the flame safeguard to detect loss of flame and de-energize the safety shut off valve.

 

 
back to top  Flame lift

 

Related Phrases :
Definition : Separation of a flame from a burner port, whilst continuing to burn with its base some distance from the port.

 

 
back to top  Flame proving period

 

Related Phrases :
Definition : The supervised period immediately following the flame establishment period and before any further operation other than shutdown is permitted.

 

 
back to top  Flame safeguard

 

Related Phrases :
Definition : A safety device that automatically cuts off the gas supply if the actuating flame is extinguished.om the port.

 

 
back to top  Flame safeguard system

 

Related Phrases :
Definition : A system consisting of a flame detector(s) plus associated circuitry, integral components, valves and interlocks, the function of which is to shut off the fuel supply to the burner(s) in the event of ignition failure or flame failure.

 

 
back to top  Flue

 

Related Phrases :
Definition : The pipe or duct through which combustion products are conveyed from a gas appliance to a discharge point, including any draught diverter, slip joint and associated duct, barometric device, fan or other fittings in the duct and includes the following.

 

 
back to top  Flue - Common

 

Related Phrases :
Definition : A flue system designed to carry combustion products from two or more appliances.

 

 
back to top  Flue - Natural Draught

 

Related Phrases :
Definition : A flue in which the draught is provided by the buoyancy effect of the hot gases in it.

 

 
back to top  Flue - Open

 

Related Phrases :
Definition : A flue system containing a draught diverter or canopy.

 

 
back to top  Flue - Secondary

 

Related Phrases :
Definition : The portion of the flue that extends from the outlet of the draught diverter to the flue terminal.

 

 
back to top  Flue - Slip Joint

 

Related Phrases :
Definition : A join in the flue (usually close to the appliance) that may be dismantled to facilitate the disconnection of the appliance from the flue.

 

 
back to top  Flue gases

 

Related Phrases :
Definition : Combustion products plus all diluents and contaminants. These include, where applicable, excess air, dilution air, process air, and waste products from the process.

 

 
back to top  Flue system

 

Related Phrases :
Definition : The passage through which flue gases are conveyed from an appliance to a discharge point including draught diverter, barometric device, fan or similar part.

 

 
back to top  Flue terminal

 

Related Phrases :
Definition : The point at which flue gases discharge from a flue.

 

 
back to top  Forced or induced draught combustion system

 

Related Phrases :
Definition : A combustion system where all or part of the air for combustion is provided by a fan or other mechanical device which is an integral part of the combustion system.

 

 

 
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G

Gas consumption Related Phrases :
Definition : The rate of energy consumed by an appliance under specific conditions and expressed in multipliers of joules per hour, for example, megajoules per hour (MJ/h) or gigajoules per hour (GJ/h).

 

 
back to top  Gas pressure regulator

 

Related Phrases :
Definition : A device that automatically regulates the outlet pressure of the gas passing through it to a predetermined value.

 

 
back to top  Gas tight

 

Related Phrases :
Definition : Meets the leak testing requirements of the appropriate Standard.

 

 
back to top  Gas/air ratio control

 

Related Phrases :
Definition : A system which simultaneously controls the flow of gas and air to a burner(s).

 

 

 
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H

High gas pressure detector Related Phrases :
Definition : A sensing device that is actuated when pressure rises above a pre-set value in it.

 

 
back to top  Hot water boiler

 

Related Phrases :
Definition : Any vessel wherein water is intended to be heated to a temperature exceeding 99C by the application of heat from the combustion products to the vessel without the generation of steam.

 

 

 
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I

Ignition temperatureor Related Phrases :
Definition : The lowest temperature at which heat is generated by combustion faster than heat is lost to the surroundings, and combustion thus becomes self-propagating.

 

 
back to top  In service

 

Related Phrases :
Definition : An appliance connected to the gas supply irrespective of the on or off status of the isolation valve.

 

 
back to top  Indoor flueless appliance

 

Related Phrases :
Definition : An indoor appliance designed to discharge its combustion products into the same room or space in which it is installed.

 

 
back to top  Injector

 

Related Phrases :
Definition : A device that causes air to mix with a stream of gas. In the case of an aerated burner it incorporates an orifice discharging gas into the mixing tube or throat.

 

 
back to top  Interlock boiler

 

Related Phrases :
Definition : A device or function that ensures that the operation of items of equipment is dependent upon the fulfilment of predetermined conditions by other items of equipment.

 

 
back to top  Intermittent pilot

 

Related Phrases :
Definition : A pilot that is automatically ignited each time the burner is started, and which is automatically extinguished with the main burner.

 

 
back to top  Interrupted pilot

 

Related Phrases :
Definition : A pilot that is automatically ignited each time the burner is started, and which is automatically extinguished at the end of the main flame establishment period.

 

 
back to top  IP Rating

 

Related Phrases :
Definition : The IP Code (http://en.wikipedia.org/wiki/Ip_rating) (or Ingress Protection Rating, sometimes also interpreted as International Protection Rating) consists of the letters IP followed by two digits or one digit and one letter and an optional letter. As defined in international standard IEC 60529, IP Code classifies and rates the degrees of protection provided against the intrusion of solid objects (including body parts like hands and fingers), dust, accidental contact, and water in mechanical casings and with electrical enclosures.

 

 

 
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L

Leakage detection system Related Phrases :
Definition : A means of checking that the safety shut off valves and the vent valves, where fitted, of a safety shut off system are gas tight, also referred to as a valve proving system.

 

 
back to top  Light back

 

Related Phrases :
Definition : Transfer of the flame from burner port(s) into the body of the burner or back to the injector.

 

 
back to top  Limit device

 

Related Phrases :
Definition : A device that is actuated by the approach to a hazardous situation in an appliance due to abnormal conditions, and when actuated, causes the gas supply to all burners to shut off with lockout.

 

 
back to top  Liquefied petroleum gas (LP gas)

 

Related Phrases :
Definition : A gas composed predominantly of any of the following hydrocarbons, or any combination of them in the vapour phase; propane, propene (propylene), butane and butene (butylene).

 

 
back to top  Liquefied petroleum gas (LP gas)

 

Related Phrases :
Definition : Liquefied petroleum gas (http://en.wikipedia.org/wiki/Liquefied_petroleum_gas)(also called LPG, GPL, LP Gas, or liquid propane gas) is a flammable mixture of hydrocarbon gases used as a fuel in heating appliances and vehicles.

 

 
back to top  Lockout

 

Related Phrases :
Definition : A safety shutdown condition of the control system that requires a manual reset in order to restart.

 

 
back to top  Low-gas-pressure detector

 

Related Phrases :
Definition : A sensing device that is actuated when the gas pressure falls below a pre-set value.

 

 
back to top  Lower explosive limit (LEL)

 

Related Phrases :
Definition : The lowest percentage of gas in a mixture of gas and air in which combustion can be selfsustaining at standard temperature (15C) and pressure (101.325 kPa absolute) conditions.

 

 

 
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M

Manual ignition Related Phrases :
Definition : The lighting of gas at a burner by a manual operation whenever gas flows from the burner.

 

 
back to top  Mixing blower

 

Related Phrases :
Definition : A motor-driven blower, the suction side of which is supplied with a mixture of air and gas from an appropriate proportioning device, which supplies a burner(s) in the immediate vicinity of the blower and has no control and/or safety device between the blower and burner.

 

 
back to top  Mixing tube

 

Related Phrases :
Definition : That part of an atmospheric burner in which the air and gas are mixed.

 

 
back to top  Modification

 

Related Phrases :
Definition : An upgrade to any or all of: gas valve train equipment; combustion/purge air system; flame safeguard system; burner management system (not involving like for like exchange of components) that changes the safety integrity of the existing system or takes the gas appliance out of its original certification criteria.

 

 

 
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N

Natural draught Related Phrases :
Definition : The flow produced by the tendency of warmed gases to rise.s are mixed.

 

 
back to top  Natural gas (NG)

 

Related Phrases :
Definition : A hydrocarbon gas consisting mainly of methane.

 

 
back to top  No-flow

 

Related Phrases :
Definition : A flow condition suitably below the normal proven air flow device setting that provides a reliable and repeatable no-flow signal from the flow device.

 

 
back to top  Nominal gas consumption

 

Related Phrases :
Definition : The appliance gas consumption, in megajoules per hour, stated in specifications, data plates, instructions and general communications.

 

 
back to top  Non-return valve

 

Related Phrases :
Definition : A device designed to operate automatically to prevent reversal of flow in a pipe.

 

 

 
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O

Open flued appliance Related Phrases :
Definition : An indoor appliance designed to be connected to an open flue system, its combustion air being drawn from the room or space in which it is installed.

 

 
back to top  Open position indicator switch

 

Related Phrases :
Definition : A switch that indicates 'open when' the valve is within 10% of the fully open position.

 

 
back to top  Operating pressure

 

Related Phrases :
Definition : The gas pressure that the consumer piping or the appliance is or will be subjected to under normal operating conditions.

 

 
back to top  Opso Regulator

 

Related Phrases :
Definition : Over-pressure shut-off (OPSO) regulators (http://www.elstergasdepot.com/repair-parts/regulator-shut-off-parts/opso.html) prevent excessive gas pressure from entering a building causing a hazardous condition. The shut-off device closes if the regulator outlet pressure rises above the maximum set point or set pressure.

 

 
back to top  Over-pressure protection system

 

Related Phrases :
Definition : A system preventing the pressure in piping or in an appliance from exceeding a predetermined value.

 

 
back to top  Over-temperature cut-out device

 

Related Phrases :
Definition : A manual reset or non-resetting device that functions to shut off the gas supply to a burner or burners to pre-vent temperature from exceeding a predetermined level.

 

 

 
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P

Parts Per Million (PPM) Related Phrases :
Definition : Parts per million (http://www.engineeringtoolbox.com/ppm-d_1039.html)- ppm - is commonly used as a measure of small levels of pollutants in air, water, body fluids, etc.

 

 
back to top  Permanent pilot

 

Related Phrases :
Definition : A pilot that is intended to be permanently alight while the appliance is in service and that is controlled independently of the main burner.

 

 
back to top  Pilot

 

Related Phrases :
Definition : A permanently located burner independent of the main burner, small in relation to it, and arranged to provide ignition for the main burner.

 

 
back to top  Position indicator switch

 

Related Phrases :
Definition : A switch that is activated when a particular position is reached.

 

 
back to top  Position-proving system

 

Related Phrases :
Definition : A means of checking that the safety shut off valves and vent valves of a double block and vent safety shut off system are in the correct position.

 

 
back to top  Pressure

 

Related Phrases :
Definition : Pressure (the symbol: P)(http://en.wikipedia.org/wiki/Pressure) is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure (also spelled gage pressure) is the pressure relative to the local atmospheric or ambient pressure.

 

 
back to top  Process after-burner

 

Related Phrases :
Definition : A gas-fired appliance used specifically for the incineration of exhaust gases containing combustible gases or dust in concentrations below the lower explosive limit.

 

 
back to top  Programmable electronic system (PES)

 

Related Phrases :
Definition : A system based on one or more central processing units (CPUs), connected to sensors and/or actuators, for the purpose of control, protection or monitoring.

 

 
back to top  Programming flame safeguard

 

Related Phrases :
Definition : A flame safeguard that automatically sequences at least two burner functions such as ignition spark, gas valve, etc.

 

 
back to top  Proof-of-closure switch

 

Related Phrases :
Definition : A switch fitted to a safety shut off valve that is only activated after the valve is closed and incorporates over-travel of the valve past the position where the valve is just closed.

 

 
back to top  Protected pilot

 

Related Phrases :
Definition : A pilot that is fitted with a flame safeguard.

 

 
back to top  Purge (or purging)

 

Related Phrases :
Definition : With respect to an appliance means the removal of combustibles.

 

 
back to top  Purge volume

 

Related Phrases :
Definition : The purge volume includes the combustion chamber and all areas where combustion products and combustible vapours, dusts or gases may accumulate in the appliance or process, up to the vertical connection of a flue or chimney that discharges directly to atmosphere.

 

 

 
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R

Rated working pressure Related Phrases :
Definition : The maximum allowable inlet pressure specified by the manufacturer.

 

 
back to top  Relief device

 

Related Phrases :
Definition : A safety device designed to forestall the development of a dangerous condition by preventing pressure, temperature or vacuum build-up.

 

 

 
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S

Safe start check Related Phrases :
Definition : A check of a flame safeguard system that will prevent an ignition attempt from occurring if the system is in the flame proved condition before any gas valves are energized as part of an ignition attempt.

 

 
back to top  Safety shut off system

 

Related Phrases :
Definition : An arrangement of valves and associated control systems that shuts off the supply of gas, when required, using a device that senses an unsafe condition.

 

 
back to top  Safety shut off system, double block and vent

 

Related Phrases :
Definition : A safety shut off system that incorporates two safety shut off valves in series, with the space between the two valves automatically vented. These valves are interlocked so that when the safety shut off valves are closed, the vent valve is open and vice versa.

 

 
back to top  Safety shut off valve

 

Related Phrases :
Definition : An automatic shut off valve that meets the requirements of AS 4629 and is used to shut off gas supply to an appliance when a signal is generated indicating the approach of an unsafe condition.

 

 
back to top  Safety shutdown

 

Related Phrases :
Definition : The action of shutting off all gas and ignition energy by means of a safety control such that restart cannot be accomplished without a full start cycle.

 

 
back to top  Set pressure

 

Related Phrases :
Definition : The mean pressure at which a device will actuate at a specific adjustment.

 

 
back to top  Simulated natural gas (SNG)

 

Related Phrases :
Definition : A gas comprising a mixture of LP gas and air, in the approximate proportions of 55% LP gas and 45% air for commercial propane.

 

 
back to top  Single Phase

 

Related Phrases :
Definition : Single Phase (http://en.wikipedia.org/wiki/Single_phase)electric power refers to the distribution of alternating current electric power using a system in which all the voltages of the supply vary in unison. Single-phase distribution is used when loads are mostly lighting and heating, with few large electric motors.

 

 
back to top  Solenoid Valve

 

Related Phrases :
Definition : A solenoid valve (http://en.wikipedia.org/wiki/Solenoid_valve)is an electromechanical valve for use with liquid or gas. The valve is controlled by an electric current through a solenoid.

 

 
back to top  Start gas

 

Related Phrases :
Definition : The gas flowing at a pilot burner, or when no pilot burner is fitted, at a main burner during the flame establishment period for initial ignition.

 

 
back to top  Steam boiler

 

Related Phrases :
Definition : Any vessel wherein steam is intended to be generated at a pressure above that of the atmosphere by the application of heat from the combustion products to the vessel.

 

 
back to top  Stoichiometric combustion

 

Related Phrases :
Definition : The theoretical combustion of fuel in air such that no combustible agent or residual oxygen remains in the combustion products.

 

 
back to top  Supervised burner

 

Related Phrases :
Definition : A burner fitted with a flame safeguard system.

 

 

 
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T

Temperature limit device Related Phrases :
Definition : A device that automatically causes the gas supply to be interrupted when the temperature at the control point reaches a predetermined limit.

 

 
back to top  Tempered liquefied petroleum gas (TLP)

 

Related Phrases :
Definition : A gas comprising a mixture of LP gas and air, in the approximate proportions of 27% LP gas and 73% air for commercial propane.

 

 
back to top  Test firing valve

 

Related Phrases :
Definition : A manual shut off valve that can be used for turning a burner on or off in order to test it for satisfactory ignition, flame stability, etc.

 

 
back to top  Thermocouple

 

Related Phrases :
Definition : Thermocouples (http://en.wikipedia.org/wiki/Thermocouple) are a widely used type of temperature sensor for measurement and control and can also be used to convert a heat gradient into electricity. They are inexpensive, interchangeable, are supplied with standard connectors, and can measure a wide range of temperatures.

 

 
back to top  Thermostat

 

Related Phrases :
Definition : A device that automatically maintains a predetermined temperature in an appliance.

 

 
back to top  Town gas (TG)

 

Related Phrases :
Definition : A gas manufactured from coal or petroleum feedstocks.

 

 
back to top  Transformer

 

Related Phrases :
Definition : An electrical transformer (http://www.ehow.com/how-does_5207362_electrical-transformers-explained.html) is a device that allows one voltage level to pass through it to be either increased or decreased.

 

 
back to top  Type A appliance

 

Related Phrases :
Definition : An appliance for which a certification scheme exists.

 

 
back to top  Type B appliance

 

Related Phrases :
Definition : An appliance, with gas consumption in excess of 10 MJ/h, for which a certification sheme does not exist.

 

 

 
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V

Valve Related Phrases :
Definition : A device for the purpose of controlling or shutting off flow.

 

 
back to top  Valve train

 

Related Phrases :
Definition : A combination of valves, regulators, pipe pieces, unions and the like that form an integrated system for flow or pressure control and safe operation of a burner.

 

 
back to top  Vent line

 

Related Phrases :
Definition : A pipe that is connected to a gas pressure regulator, relief valve or a double block and vent safety shut off system, and will convey gas to a safe location.

 

 
back to top  Vent valve, double block and vent safety shut off system

 

Related Phrases :
Definition : A valve in the vent line of a double block and vent safety shut off system that automatically opens when de-energized and automatically closes when energized.