1+ Air switching valve  
2+ Hose  
3+ Hose clip  
4+ Air pipe  
5+ Stub pipe hose  
6+ Delay valve  
7+ T-piece  
8+ Thermal vacuum valve  
9+ Stepped connector  
10+ Solenoid vacuum valve  
11+ Mounting bracket  
12+ Setscrew  
13+ Spring washer  
14+ Breather hose  
15+ Vapour hose  

The part numbers in the assembly image below relate to the product number in the table. Clicking on the part number will open up the relevant part details.