To protect the coolant from freezing
							                                
                                        
                                    
							                        
                    
                            For easier starting from cold
							                                
                                        
                                    
							                        
                    
                            To prevent the air tank from freezing
							                                
                                        
                                    
							                        
                    
                            For effective cab heating
							                                
                                        
                                    
							                        
                     
	 
	