When HVAC contractors are not aware of combustion safety they are actually creating a hazardous situation. This is because in a carbon monoxide call it may so happen that there is no crack in the heat exchanger. In such a case, the HVAC contractor might think that it was a false alarm and everything else is OK but that is not the correct approach, rather they should check for flue gases and also for depressurization. If these factors are not checked the members of a house might suffer from carbon monoxide poisoning.
When HVAC contractors do not give much importance to the airflow the efficiency of the unit might suffer considerably. It is seen that most HVAC contractors give attention to the box and not the duct work. Here it needs to be noted that when a new HVAC unit is installed it may not match with the existing duct work and there might be leaks or cracks which in turn will affect the quality of airflow. Thus, it is necessary that HVAC contractors give due importance to the existing duct work of a home.
Very often it is seen that HVAC contractors mostly focus on heating and air conditioning and they forget an important part of HVAC that is ventilation. It needs to be mentioned here that the newly constructed buildings have a tighter design but they might have weaknesses in ventilation. The weakness in ventilation might cause misbalance of pressure in various rooms and the airflow might also be restricted. Thus, it is recommended that HVAC contractors give proper attention to ventilation so that there is proper airflow in the house.