L3 Central Heating Revision

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Question 1 of 73

Which one of the following is the name of the point at which an expansion vessel connects to a central heating system?

Select one of the following:

a) Negative point.
b) Neutral point.
c) Positive point.
d) Central point.

Explanation

Question 2 of 73

Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

a) Fully pumped system with 2 x two port valves.
b) Fully pumped system with mid-position valve.
c) Pumped heating with unvented hot water.
d) Sealed central heating system.

Explanation

Question 3 of 73

Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

a) Pumped heating with unvented hot water.
b) Fully pumped system with 2 x two port valves.
c) Sealed central heating system.
d) Fully pumped system with 3 ports valve.

Explanation

Question 4 of 73

Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

a) Fully pumped system with 2 x two port valves.
b) Fully pumped system with mid-position valve.
c) Pumped heating with unvented hot water.
d) Sealed central heating system.

Explanation

Question 5 of 73

Which one of the following is the likely effect on the heating system when the pump is positioned as shown in the Figure?

Select one of the following:

a) The system is put under neutral pressure.
b) The system is put under positive pressure.
c) Water is likely to be pumped over the vent.
d) Air would be sucked in through the vent.

Explanation

Question 6 of 73

Which one of the following is the likely effect on the heating system when the pump is positioned as shown in the Figure?

Select one of the following:

a) The system is put under neutral pressure.
b) The system is put under positive pressure.
c) Water is likely to be pumped over the vent.
d) Air would be sucked in through the vent.

Explanation

Question 7 of 73

In the central heating system shown in the Figure , what is the name of Component A

Select one of the following:

a) Zone valve.
b) 3 port mid position valve.
c) Pressure relief valve.
d) Automatic air vent.

Explanation

Question 8 of 73

Which one of the following is the name of Component A shown in the Figure?

Select one of the following:

a) Automatic by-pass valve.
b) Wheel head valve.
c) 2 port motorised valve.
d) Air separator.

Explanation

Question 9 of 73

14 Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

a) Fully pumped system with 2 x two port valves.
b) Fully pumped system with mid-position valve.
c) Pumped heating with gravity primary flow and return.
d) Sealed central heating system.

Explanation

Question 10 of 73

Which one of the following is the likely effect on the heating system when the pump is positioned as shown in the Figure?

Select one of the following:

a) The system is put under negative pressure.
b) The system is put under positive pressure.
c) Water is likely to be pumped over the vent.
d) Air would be sucked in through the vent.

Explanation

Question 11 of 73

Which one of the following shown in the Figure is a manufacturer’s replacement part for a typical gas fired combination boiler?

Select one of the following:

a) Compact thermal module.
b) Fan assembly.
c) Secondary heat exchanger.
d) Burner assembly.

Explanation

Question 12 of 73

What type of open vented system is shown in the diagram?

Select one of the following:

a) Fully pumped with two mid position valves.
b) Partially pumped heating with gravity hot water.
c) Fully pumped with 2 x two port valves.
d) Partially pumped using a mid position valve.

Explanation

Question 13 of 73

Which one of the following types of heating system uses the components In the image shown?

Select one of the following:

a) C Plan.
d) W Plan.
c) S Plan.
b) Y Plan,

Explanation

Question 14 of 73

Which one of the following Is a correct description of the circuit shown?

Select one of the following:

A- Fully pumped hot water and multiple space heating system.
B- Fully pumped incorporating two 2 port valves.
C- Fully pumped incorporating a 3 port valve.
D- Fully pumped heating, gravity hot water.

Explanation

Question 15 of 73

which one of the following heating systems is Indicated by the wiring diagram shown?

Select one of the following:

A- Fully pumped hot water and multiple space heating system.
B- Fully pumped incorporating two 2 port valves.
C- Fully pumped incorporating a 3 port valve.
D- Fully pumped heating, gravity hot water.

Explanation

Question 16 of 73

Which one of the following heating systems is indicated by the wiring diagram shown?

Select one of the following:

a) S plan plus
b) C plan plus
c) W plan
d) Y plan

Explanation

Question 17 of 73

What type of heating component is shown in the image?

Select one of the following:

A- a pressure gauge.
B- an automatic air vent
C- an electric thermostat
D- a temperature gauge.

Explanation

Question 18 of 73

Both the pressure relief and temperature control valves fail in a sealed heating system. What is the likely outcome in such situation?

Select one of the following:

A- The boiler may stop working.
B- The pump may stop working
C- The pressure vessel may explode.
D- The pressure vessel may overflow.

Explanation

Question 19 of 73

what type of gas heating boiler component is shown In the Image?

Select one of the following:

A- Boiler hood.
B- heat exchanger.
C- pressure gauge.
D- a gas burner.

Explanation

Question 20 of 73

What type of gas heating boiler component is shown in the image?

Select one of the following:

A- water thermostat.
B- diverter valve.
C- air pressure switch.
D- Multifunctional valve.

Explanation

Question 21 of 73

According to the Domestic Heating Compliance Guide, a device that takes heat energy from a low-temperature source and upgrades it to a temperature that could be used for heating, is known as a:

Select one of the following:

a) heat pump
b) solar heating panel
c) combined heat and power boiler
d) condensing boiler

Explanation

Question 22 of 73

Which one of the following is used to indicate the U value through a building fabric?

Select one of the following:

a) W/m² ºC.
b) W/m³ ºC.
c) W x r ºC.
d) W + r ºC.

Explanation

Question 23 of 73

Which one of the following Building Regulations covers the requirements for combustion appliances?

Select one of the following:

a) Part A (C in Northern Ireland).
b) Part J (N in Northern Ireland).
c) Part L (K in Northern Ireland).
d) Part P (P in Northern Ireland).

Explanation

Question 24 of 73

Which one of the following government departments provides information on the Boiler Efficiency Database?

Select one of the following:

a) DfES. (Department for Education and Skills ..(DfES)
b) DEFRA. (Department for Environment, Food and Rural Affairs (Defra)
c) BERR. (Department for Business, Enterprise and Regulatory Reform)
d) DIUS. (Department for Innovation, Universities and Skills)

Explanation

Question 25 of 73

A central heating system in which the water supplied to the system is fed directly from the cold water supply pipe is

Select one of the following:

a) open vented fully pumped
b) open vented gravity
c) unvented hot water
d) sealed system

Explanation

Question 26 of 73

According to the Domestic Heating Compliance Guide, what is the minimum SEDBUK value for a gas or oil fired central heating boiler installed in an existing dwelling after 1 April 2007?

Select one of the following:

a) 76%.
b) 80%.
c) 82%.
d) 86%.

Explanation

Question 27 of 73

Which one of the following methods is usually preferred for determining the boiler output when replacing an existing oil or gas fired boiler?

Select one of the following:

a) Replace like for like.
b) Whole house boiler sizing method.
c) Add 30% to existing output.
d) Only use SEDBUK band D boilers.

Explanation

Question 28 of 73

According to the Domestic Heating Compliance Guide, which one of the following organisations operates an approvals scheme for solid fuel boilers and heating appliances?

Select one of the following:

a) CORGI.
b) OFTEC.
c) HETAS.
d) NICEIC.

Explanation

Question 29 of 73

Which one of the following should be the minimum distance, in mm, between a boiler flue and any combustible material when it passes through a cupboard?

Select one of the following:

a) 10.
b) 15.
c) 25.
d) 50.

Explanation

Question 30 of 73

Which one of the following would be the most desirable pump location in an open vented fully pumped central heating system?

Select one of the following:

Explanation

Question 31 of 73

The condensate pipework from a high efficiency (condensing) boiler should be laid at a minimum fall of

Select one of the following:

a) 1.5º
b) 2.5º
c) 5º
d) 10º

Explanation

Question 32 of 73

Which one of the following test methods is used to determine the soundness of a central heating system?

Select one of the following:

a) Hydraulic pressure.
b) Visual inspection.
c) Hydrostatic pressure.
d) Pneumatic pressure.

Explanation

Question 33 of 73

The minimum size of earthling cable, in mm, used to bond the main services in a domestic property is

Select one of the following:

a) 2.5 mm2
b) 6 mm2
c) 10mm2
d) 12 mm2

Explanation

Question 34 of 73

Which one of the following items of equipment could be used to test temperature differential between the heating flow and return pipework?

Select one of the following:

a) Multi-meter
b) Manometer.
c) Ammeter.
d) Digital thermometer.

Explanation

Question 35 of 73

The pressure gauge in a sealed heating system should be capable of reading a pressure range, in bars, of

Select one of the following:

a) 0 to 3
b) 0 to 4
c) 1 to 4
d) 2 to 5.

Explanation

Question 36 of 73

When commissioning a gas fired combination boiler, which one of the following activities should be carried out after turning on the mains water supply?

Select one of the following:

a) Check the water level is correct in the CWSC.
b) Purge the hot water pipework of air.
c) Check the water level is correct in the F&E cistern.
d) Isolate the boiler at the fused spur outlet.

Explanation

Question 37 of 73

Information related to the performance specification of an LPG fired central heating boiler is obtained from

Select one of the following:

a) SEDBUK
b) Building Regulations Part L (F in Northern Ireland)
c) Manufacturer’s instructions
d) CORGI.

Explanation

Question 38 of 73

When commissioning a gas fired system boiler, adjustment to the heat output of the boiler is achieved by

Select one of the following:

a) adjusting the room thermostat
b) adjusting the cylinder thermostat
c) range rating the boiler
d) balancing the system.

Explanation

Question 39 of 73

Which one of the following would be the first action prior to de-commissioning a central heating system in an unoccupied dwelling?

Select one of the following:

a) Seek permission to carry out the work from the Local Authority.
b) Contact the utility services to isolate the gas and electricity supplies to the building.
c) Ensure that the content of the heating system is drained into containers and disposed of.
d) Ensure that all the incoming services have been safely isolated.

Explanation

Question 40 of 73

Which one of the following would contain a fault finding chart for a specific solid fuel boiler?

Select one of the following:

a) HETAS manual.
b) Domestic Heating Compliance Guide.
c) OFTEC manual.
d) Manufacturer’s instructions.

Explanation

Question 41 of 73

When determining the output of a gas central heating boiler, how many kW should be allowed for the hot water heating circuit with a cylinder of 100 – 120 litres?

Select one of the following:

a) 2 kW.
b) 4 kW.
c) 6 kW.
d) 8 kW.

Explanation

Question 42 of 73

Which one of the following should be included on a Benchmark Service Interval Record?

Select one of the following:

a) Flow and return temperature.
b) Gas inlet pressure.
c) Gas Safe Register ID card serial number.
d) Gas flue analysis results.

Explanation

Question 43 of 73

The Domestic Heating Compliance Guide refers to ‘boiler interlock’. This can be described as a

Select one of the following:

a) wiring arrangement preventing the boiler from firing when each circuit has shut off
b) security setting on the boiler to prevent the possibility of tampering by the customer
c) wiring arrangement to remove the residual heat from the boiler to the heat leak radiator
d) system of isolating the boiler when the frost thermostat is activated.

Explanation

Question 44 of 73

According to the Domestic Heating Compliance Guide, a heating system that supplies heat to a number of dwellings from a common heat source is known as

Select one of the following:

a) combination heating
b) community heating
c) central heating
d) combined heat and power.

Explanation

Question 45 of 73

On boilers fitted with digital displays, which one of the following display codes takes priority over other codes?

Select one of the following:

a) Status.
b) Diagnostic.
c) Fault.
d) Memory.

Explanation

Question 46 of 73

Which one of the following government departments provides information on the Boiler Efficiency Database?

Select one of the following:

a) DfES.
b) DEFRA.
c) BERR.
d) DIUS.

Explanation

Question 47 of 73

Guidance on how to satisfy the Building Regulations energy efficiency requirements when carrying out central heating work on new buildings can be found in

Select one of the following:

a) Approved Document E (B in Northern Ireland)
b) Approved Document G (C in Northern Ireland)
c) Approved Document J (E in Northern Ireland)
d) Approved Document L1A (F1 in Northern Ireland).

Explanation

Question 48 of 73

When installing a high efficiency (condensing boiler), provision must be made for a

Select one of the following:

a) discharge pipe run to a drain or soakaway
b) double check valve to be installed on the primary flow
c) single check valve to be installed on the vent pipe
d) flow meter to be installed on the gas valve.

Explanation

Question 49 of 73

Which one of the following is the normal pressure for soundness testing a wet central heating system?

Select one of the following:

a) 0.5 times the maximum operating pressure.
b) 1.5 times the maximum operating pressure.
c) 2 times the maximum operating head.
d) 2.5 times the maximum operating head.

Explanation

Question 50 of 73

Which one of the following is the correct size of fuse, in amps, for protecting a domestic central heating circuit?

Select one of the following:

a) 3 amp
b) 5. amp
c) 13. amp
d) 16. amp

Explanation

Question 51 of 73

The pressure relief valve in a sealed heating system should discharge at what pressure?

Select one of the following:

a) 1bar
b) 2 bars
c) 3 bars
d) 4 bars

Explanation

Question 52 of 73

The meaning of the status codes on the digital display indicator on a central heating boiler can be obtained from

Select one of the following:

a) inside the combustion chamber
b) SEDBUK
c) Manufacturer’s instructions
d) SBGI.

Explanation

Question 53 of 73

Information related to the performance specification of a natural gas fired central heating boiler is obtained from

Select one of the following:

a) CORGI
b) Building Regulations Part L (F in Northern Ireland)
c) SEDBUK
d) Manufacturer’s instructions.

Explanation

Question 54 of 73

When commissioning central heating systems, manufacturers generally recommend that the system is

Select one of the following:

a) flushed, run at operating temperature, drained, flushed and re-charged
b) tested at operating temperature for 30 minutes at 0.5 times operating pressure
c) left for a period of 24 hours before being put into service after commissioning
d) tested at 0.5 times normal operating temperature for 15 minutes.

Explanation

Question 55 of 73

Which one of the following system components provides an indication that a sealed central heating system has been installed?

Select one of the following:

a) Heat leak radiator.
b) mid position valve.
c) Expansion vessel.
d) Air separator.

Explanation

Question 56 of 73

Which one of the following would contain a fault finding chart for a specific high efficiency gas systems boiler?

Select one of the following:

a) British Standard 6700.
b) Domestic Heating Compliance Guide.
c) Manufacturer’s instructions.
d) British Standard 5449.

Explanation

Question 57 of 73

Insufficient water flow rate through the heat exchanger of a boiler is usually the cause of

Select one of the following:

a) kettling
b) temperature relief discharge
c) pressure relief discharge
d) boiler overrun.

Explanation

Question 58 of 73

Your Diploma in plumbing level 3 is an NVQ qualification

Select one of the following:

True
False

Explanation

Question 59 of 73

When completing your plumbing L3 diploma you will be gas qualified engineer

Select one of the following:

True
False

Explanation

Question 60 of 73

The Gas (Installation & Use), Regulation 3, specifies the qualifications required to carry out work in relation to gas fittings and gas storage. Which one of the following describes the minimum level of qualification required?

Select one of the following:

A) A fully qualified plumber to NVQ Level 3 standard.
B) A member of a class of person approved by HSE
C) A person regularly attending manufacture appliance training courses
D) A person that has successfully completed an accredited course

Explanation

Question 61 of 73

What is the main feature when designing a space heating circuit to a dwelling with a floor area In excess of 150 m²

Select one of the following:

a) A single zone with weather compensated control and optimum start.
b) A single zone with optimum start and TRVs on all radiators
c) Multiple zones with separate time and temperature controls
d) Multiple zones with a single time controller and TRVs on each radiator.

Explanation

Question 62 of 73

Which one of the following identifies this process occurs whereby the outside temp of the building is measured in order to adjust the heating start time?

Select one of the following:

a) Optimum start.
b) Delayed start.
c ) Thermo start
d) Manual start.

Explanation

Question 63 of 73

which one of the following statements best describes the function of a Boiler interlock

Select one of the following:

a) A bypass arrangement in the primary flow and return to assist the boiler in removing excess hot water.
b) A wiring arrangement that permits the frost stat to override all other controls when the outside temperature rises
c) An arrangement permitting hot water to be obtained without the heating circuit being in operation
d) A wiring arrangement that prevents the boiler firing unless there IS a demand from either the water of space heating

Explanation

Question 64 of 73

Work is being undertaken on the wiring centre of a central system. Which one of the following actions should be taken in addition to switching off the electrical supply at the fuse spur?

Select one of the following:

a) Ask the customer to turn off the supply and explain it is their responsibility.
b) Use a notice which is placed on the consumer unit stating “Do not use”
c) Remove and retain the fuse and check for safe isolation of the supply.
d) Turn off the electrical supply and carry out the work methodically.

Explanation

Question 65 of 73

A ring final circuit requires the addition of a fused connection for a boiler. Which one of the following indicate the most suitable location to conduct safe isolation in order to carry out this work

Select one of the following:

a) The consumer Unit main switch.
b) The circuit breaker for the circuit
c) The boiler time clock/controller.
d) At the supplier's main cut out fuse

Explanation

Question 66 of 73

What does the use of low loss headers on multi boiler central heating installations enable?

Select one of the following:

A- Smaller capacity F&E cisterns
B- A number of balanced independent pump circuits.
C- filling loop to be of smaller diameter.
D- A reduction in operating pressure in the system.

Explanation

Question 67 of 73

Which one of the following identifies the most important factor when calculating the pipework size for a heating system?

Select one of the following:

A- Water density
B- Water velocity.
C- Water hardness
D- Water viscosity.

Explanation

Question 68 of 73

For safety reason, it is important for pressure relief valves to be installed correctly. At what pressure Is a pressure relief valve on a combination boiler normally set to discharge

Select one of the following:

A- 1.5 bar.
B- 2 5 bar.
C- 3 bar.
D- 3.5 bar

Explanation

Question 69 of 73

which one of the following best describes an advantage of using a sealed central heating system?

Select one of the following:

A- lt is less expensive to install.
B- lt can serve longer dead legs
C- lt has a manual test devise.
D- lt produces more heat

Explanation

Question 70 of 73

In a sealed central heating system, which one of the following replaces the open vent pipe in a conventional system?

Select one of the following:

A- Filling loop.
B- Non-return valve.
C- Pressure relief valve
D- Temperature and pressure gauge.

Explanation

Question 71 of 73

The most appropriate position for an expansion vessel is indicated by which one of the following points in the system?

Select one of the following:

A- the highest point.
B- the lowest point.
C- the coolest part of the system.
D- the hottest part of the system.

Explanation

Question 72 of 73

Which type of fuel would not be used in rural areas of the UK where access to a piped fuel supply Is unavailable?

Select one of the following:

A- Fuel oil
B- Natural gas.
C- Heat pumps.
D- Solid fuel.

Explanation

Question 73 of 73

which one of the following boilers requires a drainage pipe to discharge the water produced during the combustion process?

Select one of the following:

A- back boiler
B- combination boiler.
C- independent boiler
D- Condensing boiler.

Explanation

Check answer

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Central heating revision

L3 Central Heating Revision

Question 1 of 73

Which one of the following is the name of the point at which an expansion vessel connects to a central heating system?

Select one of the following:

Explanation

Question 2 of 73

Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

Explanation

Question 3 of 73

Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

Explanation

Question 4 of 73

Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

Explanation

Question 5 of 73

Which one of the following is the likely effect on the heating system when the pump is positioned as shown in the Figure?

Select one of the following:

Explanation

Question 6 of 73

Which one of the following is the likely effect on the heating system when the pump is positioned as shown in the Figure?

Select one of the following:

Explanation

Question 7 of 73

In the central heating system shown in the Figure , what is the name of Component A

Select one of the following:

Explanation

Question 8 of 73

Which one of the following is the name of Component A shown in the Figure?

Select one of the following:

Explanation

Question 9 of 73

14 Which one of the following types of central heating system is shown in the Figure?

Select one of the following:

Explanation

Question 10 of 73

Which one of the following is the likely effect on the heating system when the pump is positioned as shown in the Figure?

Select one of the following:

Explanation

Question 11 of 73

Which one of the following shown in the Figure is a manufacturer’s replacement part for a typical gas fired combination boiler?

Select one of the following:

Explanation

Question 12 of 73

What type of open vented system is shown in the diagram?

Select one of the following:

Explanation

Question 13 of 73

Which one of the following types of heating system uses the components In the image shown?

Select one of the following:

Explanation

Question 14 of 73

Which one of the following Is a correct description of the circuit shown?

Select one of the following:

Explanation

Question 15 of 73

which one of the following heating systems is Indicated by the wiring diagram shown?

Select one of the following:

Explanation

Question 16 of 73

Which one of the following heating systems is indicated by the wiring diagram shown?

Select one of the following:

Explanation

Question 17 of 73

What type of heating component is shown in the image?

Select one of the following:

Explanation

Question 18 of 73

Both the pressure relief and temperature control valves fail in a sealed heating system. What is the likely outcome in such situation?

Select one of the following:

Explanation

Question 19 of 73

what type of gas heating boiler component is shown In the Image?

Select one of the following:

Explanation

Question 20 of 73

What type of gas heating boiler component is shown in the image?