Chimney and Flue
Flue Inspection and Testing
Regulations
Gas Supply
Safety Devices and Controls
Pipework
Ventilation
Unsafe Situations
Commissioning
Gas Performance
Gas Pipework
Chimney and Flue
Combustion
Boilers
Flue Inspection and Testing
- clips are not more than 1.8m apart
- bends are not more than 45° (30° - for pre-cast flue)
- Flue-flow testing using a Smoke Pellet (5m3 of smoke within 30 sec)
- Spillage testing using Smoke Matches
| Characteristic |
Natural gas |
Propane |
Butane |
| Specific gravity |
0.6 |
1.5 |
2.0 |
| Calorific value |
39MJ/m3 |
93MJ/m3 |
122MJ/m3 |
| Stoichiometric air requirements |
10:1 |
24:1 |
30:1 |
| Supply pressure |
21mbar |
37mbar |
28mbar |
| Flammability limits |
5-15% |
2-10% |
2-9% |
| Flame speed |
0.36m/sec |
0.46m/sec |
0.45m/sec |
| Ignition temperature |
704°C |
530°C |
408°C |
| Flame temperature |
1930°C |
1980°C |
1996°C |
