• HVAC is an acronym for a system of processes that work together: heating, ventilating and air conditioning. These three systems are integrated in the home so that you can be cool in the summer and warm in the winter. However, HVAC systems do fail: the fan or condensor can break; the vents can clog; the sensors can stop reading the temperature. Any of these failures requires a technician or home repair enthusiast to use specific tools on the HVAC system.
  
  

Condensor Water Removal Pump

• The condensor in an HVAC system condenses gas into liquid, and in the process removes heat from the original matter, thereby cooling a room. The liquid produced in the system is drained out, but sometimes the drain is clogged or excess water builds up. In this case, technicians or repair people have to vacuum the water up with a wet vac or pump it out with a water removal pump. The water pump works by connecting it to the main drain line and pumping out all the water from the system.
  
  

Drain Guns

• Drain guns use compressed air, carbon dioxide or nitrogen to blast away clogs in the drain lines of HVAC systems. They attach to an opening at a drain line. Drains can clog from an accumulation of grit, dirt and other particles. This buildup can block drainage flow and stop the action of condensing gas into a liquid, necessary to remove heat from a room.
  
  

Carbon Monoxide Meters

• Furnaces eject toxic gases, such as carbon monoxide, through the flue, which takes the toxic gas out of the building. Carbon monoxide meters test whether the flue is ejecting carbon monoxide and that there is no carbon monoxide buildup in the house. Inspectors use these devices by drilling a small hole in a flue chimney and inserting the probe into it in order to test the carbon monoxide levels.