Cold Air Return Ductwork

The hot air goes up into the plenum and from there flows to the supply trunk line image 3 where it is distributed through vents throughout the rest of the home.

Cold air return ductwork.

First building codes in many areas require that the cold air return line gets external insulation and therefore you will need to leave a gap for the insulation around the duct return line. The conditioned air then re circulates back into the system as needed. Therefore your return air duct and grill size will be 24 by 24 inches tip. In addition its flexibility allows for easier installation in hard to reach areas.

A furnace return system must collect all the air being put out by that system. An insufficient return system or one too large will reduce the efficiency of the heating and increase energy bills. Return air ducts are necessary for just about every room. A cold air return vent is necessary for optimal functioning of your heating system.

For each cubic foot of air that is pumped out into your home the same amount must be drawn back in so the process can start over. Lambro rigiflex 4 in x 96 in aluminum semi rigid flexible duct. Diameter of duct x 3 14 return air duct in square inches. Step 4 calculate the square root of the total.

4 ton unit x 144 square inches 576 squared. Return cold air from registers to the furnace so that it will run properly. They do precisely what the name implies. Yes if your house is either hot or cold i ll bet you have inferior or lacking return air ducts.

If you live in a home that has rooms that are either too hot in hot weather or are cold in cold weather you could have a return air duct issue. Used as a central return vent box filter grill not included. Can be easily cut to size. Every building that uses forced hot air for heating will have cold air return vents.

If the furnace is putting out 1 000 cubic feet per minute of air flow the return system must collect 1 000 cubic feet and take it back to the unit. Can accept any size collar up to 18 in. Return vents also provide air circulation. Menards offers a wide range of ductwork pipe and fittings to help your ductwork systems run efficiently these products are used for warm air return supply and exhaust systems.

The square root of 576 is 24. Item 1790033 model 1790033. Cold air returns in order for your ductwork system to operate properly the furnace must have a consistent source of air that is cycled back into the unit. Flexible duct can be installed in place of galvanized pipe in many applications if allowed by your local hvac codes.

During cold weather gas burners create heat in the heat exchanger image 2 which in turn heats the air.