NEW
Font size
WorksheetsL3 ventelation,flues,combustion
Total questions: 25
Worksheet time: 13mins
Working pressure is that pressure measured
at the meter when?
All appliances are turned off
3 cooker burners are lit, or any other appliance full on
The supply is open to atmosphere
all appliances turned full on
When an air vent is installed on the internal wall of a
property the vent must be sited not?
less than 450mm from floor level
more than 450mm from floor level
more than 450mm from ceiling level
less than 450mm from ceiling level
The ventilation requirement for open flued
appliances is dependent upon?
the maximum heat input
the maximum heat output
room dimensions
room dimensions
What action should the gas operative take if an air
vent, of adequate size, but fitted with a fly
screen is encountered?
Install another air vent of the same size with a fly screen
Remove the fly screen
Leave the vent and instruct the user to clean regularly
Disconnect the appliance and label as At Risk
An open flued combination boiler with hot water
input of 36kW (gross) and heating input of 21 kW
(gross) is fitted in a kitchen measuring 2.5m by 2.2m
by I .8m. What is the vent free area required?
59.6 cm2
127.1 cm2
186.6 cm2
A 16kW (Net) input open flued boiler fitted in a kitchen, with an external door and openable window, and having a volume of 11m3 also has a gas cooker installed. What ventilation area is required?
45 cm2
95 cm2
No additional ventilation required
A room sealed boiler with a range rated burner from
16 kW to 21 kW (gross) is fitted in a compartment
and set to I 8.5 kW (gross). What is the required
ventilation direct to outside?
94 cm2 both top and bottom
189 cm2 both top and bottom
83 cm2 both top and bottom
200 cm2 both top and bottom
A room sealed combination boiler with hot water
input of 33kW and heating input of 25kW is fitted in a
kitchen measuring 2.5m by 2.2m by I .8m. What is
the vent free area required?
78 cm2
No vent required
114 cm2
The purpose of the top vent installed within a
compartment is to:
Assist the pull of the flue
Supply air for combustion
Remove warm air for cooling
Reduce the pull of the flue
When installing two or more internal ventilators to
provide air for combustion they must be:
all the same size
50% over sized
25% over sized
white in colour
Where an extract fan is in the same room as an air
brick providing air for combustion:
an additional 50cm2 should be added
the fan must be disconnected
the fan can only blow inwards
an additional 100cm2 should be added
Flue blocks installed after 1986, must have a
minimum internal dimension of?
150mm
100mm
90mm
75mm
The minimum void dimension below an appliance
connection on an unlined brick chimney is?
100 mm – 10 litre
250 mm – 12 litre
75mm – 2 litre
80mm – 8 litre
When shielding plastic gutter from a flue terminal the
minimum air gap between the shield and the gutter
should be?
25mm
15m
1mm
5mm
A flue serving a gas fire , on an external wall should
be lined when it is above?
9 metres high
10 metres high
12.5 meres high
15 metres high
An open flued fire with an Oxygen Depletion Sensing
Device is permitted in a Bedroom if?
it is above 14 kW input
it is below 14 kW input
it is below 7 kW input
its input is irrelevant
A precast flue block installation dating from the
1970’s would be expected to have a cross
sectional area of?
12000 mm2
16000 mm2
13000 mm2
The Gas Safety (Installation and Use) Regulations
apply to touring caravans ONLY when
hired out in the course of a business?
True
False
Non-metallic gas pipe can only be used to convey
gas if it is?
black in colour
yellow in colour
a pipe connected to a readily movable flueless appliance or a sleeved pipe entering a building
a pipe connected to a readily movable appliance
Any newly installed gas appliance which CAN
NOT be used safely?
must be labeled, “Do Not Use”
can be left connected to the supply
cannot be left connected to the gas supply
is safe to be left connected providing the user is told of the situation
A tenant agreeing to have safety work done
DISCHARGES the landlord from their obligations
under The Gas Safety (Installation and
Use) Regulations for landlord safety checks?
True
False
Where the responsible person refuses to allow an
unsafe appliance to be disconnected, the
installer shall?
turn off appliance and inform TRANSCO
inform Gas Safe Register
do nothing to the appliance
turn off appliance and write to the responsible person
A gas fire and back boiler of inputs 7kW and 16kW
respectively fitted in 1999, in a bed sitting
room. What are the ventilation requirements?
72 cm2
103.5 cm2
80 cm2
Installation not allowed
To convert Btu’s to kW you?
multiply by 3412
divide by 3412
multiply by 1040
divide by 1040
To change the Gross input of an appliance to Net
you?
÷ by 1.11
x by 1.11
÷ by 1.1
÷ by 1.1
