Consequences of over-sized system-
Many heating and cooling contractor may tempt you into buying an over sized unit. Mark, they do it to feather their own nest. Never assume that an over sized system will cool or heat the house better. An over sized unit can generate following problems -
• It consumes more energy as it is larger size.
• It short-cycles and it heat or cools a smaller space faster. A lot of energy is also wasted through short-cycling.
• The unit will be noisy as it will supply more air through the vents than is required by the rooms.
• The frequent temperature swing due to the large system will make you uncomfortable; it will be unable to maintain the appropriate humidity level, as it will not run for long each cycle.
• Short cycling will lead to rapid wear and tear of the air conditioner.
• It fails to remove sufficient humidity from the air since it doesn't run long enough to provide adequate humidity control.
Consequences of undersized system-
Don’t be tempted to buy a too-small system to save money. The saving will go into energy bills that you will pay at the end of each month. Here are the results of an undersized unit -
• As it is capacitated to cool or heat a big house, it will run continuously to render the desired comfort. This will shoot-up the power bills.
• It will be able to provide the desired comfort making the house hotter in summer and cooler in winter
• If it is unable to provide you the desired comfort, it will depend upon supplemental form of heating or cooling. This will be very costly in terms of operation.
• It can create unnecessary noise. This is will be more acute if the ducts are also undersized, compared to what is required by your house.
• As it will be running continuously, its lifespan will be shortened; you will generate frequent repair bills due to breakdowns and multi-functioning.
• A good side of an undersized unit is that it will provide effective humidity control as it will run longer each cycle.