Overall Revision Flashcards
9 kW Open Flue boiler, What is the ventiliation requirement?
Check the data badge, take away 7 kW for adventitaious air and multiply the the remaining 2 kW by 5. Answer is 10 cm2 Ventilation required and an openable window/door leading to the outside.
5 kW Open Flue boiler, What is the ventiliation requirement?
Below 7 kW so adventitious air eliminates the the need for ventilation requirements.
28 kW Room sealed boiler within a compartment ventiliated to the outside, what are the ventiliation requirements?
Top Vent: 28 kW x 5 cm2
Bottom Vent: 28 kW x 5 cm2
18 kW Open Flue boiler within a compartment, ventiliated via an internal room, what are the ventiliation requirements?
Top Vent: 18 kW x 10 cm2 = 180 cm2
Bottom Vent: 18 kW x 20 cm2 = 360 cm2
As we are ventilating to an internal room, a vent is required for combustion air direct from outside.
Effective free area of vent = 18 kW - 7 kW
= 11 kW x 5 cm2
= 55 cm2
9 kW Open Flue boiler within a compartment, ventiliated to the outside, what are the ventiliation requirements?
Top Vent: 9 kW x 5 cm2 = 45 cm2
Bottom Vent: 9 kW x 10 cm2 = 90 cm2
As the compartment ventiliation is direct to outside, no further requirement for additional combustion ventiliation.
What are the flamability limits of Natural Gas?
5-15 %
What is the minimum distance that copper pipe should be from an electrical socket or light switch?
25 mm
Minimum distance that the gas meter should be from a fuse box?
150mm
Unsafe Situations for a flueless cooker?
Cooker bayonet to have a clean U bend looking downwards and be 750 mm distance above the ground level.
Does the cooker have a chain if it is isolated?
The safety lid works properly.
Overall good condition of the appliance?
No water fitting used for cooker pipework?
Not installed in a bathroom.
Correct ventilation?
What is the minimum distance a flue should be from a window?
300mm
How often should a flue be supported?
Every 1.8m
How often should a room sealed boiler be supported?
Every 2m
How far should the guard be from the terminal?
50mm
Where should a carbon monoxide alarm be located?
Between 1m and 3m from the appliance.
Where should the carbon monoxide be if wall mounted?
1.5m from floor level and at least 150 mm below the ceiling but highier than any window or door within the room.
Where should the carbon monoxide alarm be if ceiling mounted?
At least 300 mm away from any wall
When completing a combustion analysis procedure, how long should the level of CO be monitored?
15 minutes.
What is the specific gravity of Natural Gas?
0.6
Ventilation required for a flueless appliance if room size is 8 m3?
50 cm2 ventiliation and a window/door leading directly to the outside.
Ventilation required for a flueless appliance if room size is 4 m3?
100 cm2 ventilation + openable window or door leading to the outside.
Ventilation requirements for a flueless appliance if room size is above 10 m3?
Just a window or door leading to the outside.
How much ventilation does a DFE require?
Most require a 100 cm2 air vent with adventitious air already taken off.
Name 4 parts of an Open Flue?
Primary Flue, Down draught diverter, secondary flue and a terminal.
What is the minimum distance that the vertical chimney is required above the appliance/draught diverter?
600 mm
What is the minimum circular CSA of a chimney with gas blocks?
16500 mm2
What is the minimum circular CSA of a new gas fire?
12000 mm2
Offset blocks, what is the minimum offset?
30 degrees
Approved terminals should be designed with an entry of what size?
6mm ball but prevent entry of a 16mm ball.
At what size chimney diameter, should it have an approved terminal?
170mm or less.
What minimum distance chimney flashing is required?
150 mm
Chimney outlets based on a ridge, how far should the terminals be apart?
50 mm and should terminate at the same height
Chimney outlets based on a ridge which are open on all 4 sides, should be at least how far apart?
300 mm
What is the first gas family? What is the second gas family? What is the third gas family?
1st - Manufactored gas. 2nd - Natural gas. 3rd - LPG.
