Everyone hates wasting money.

That’s why some Kansas homeowners think, “Why bother cooling a room in my home I barely use? I’m going to shut the air vents so I don’t waste energy!”

That sounds nice in theory. I mean, those vents blowing out air have little levers. So you should be able to use them, right?

But closing those vents can actually:

Make you uncomfortable in other parts of your home Cost you money Damage your heating/cooling system We’ll explain why in this nifty article.

How closing vents makes you uncomfortable To understand why closing vents can make you uncomfortable, let’s back up for a second and describe how your cooling/heating system distributes air in your home:

The inside unit has a blower that pulls in air from your home via return grilles.
The AC or furnace cools or heats that air.
The blower pushes that cooled or heated air out the supply vents (the thing homeowners try to close).
Keep in mind: That blower is designed to push against air up to a maximum pressure. But if you close a vent, you’re increasing pressure in your duct system.

This causes the blower to keep running but at a lower speed. So now you have less air coming out supply vents in rooms you are using, leaving you uncomfortable.

In addition, the increased pressure in the duct system will make the blower work harder, decreasing its efficiency.
That’s dangerous because now they’re not absorbing enough heat (in the case of the evaporator coil) or giving up enough heat (in the case of the heat exchanger).

Here’s how that can cause costly damage:

In the summer, the AC’s evaporator coil will get too cold and turn into a block of ice (reducing airflow). Eventually liquid refrigerant flows back to the AC compressor, destroying it.
In the winter, the furnace’s heat exchanger will get too hot, crack and possibly distribute poisonous carbon monoxide throughout your home.
For the love of your system, don’t close air vents
Now we’re not saying closing one vent will cause all of these problems. But closing multiple vents and keeping them that way certainly can.

Duct Air Conditioner

There are a lot of advantages to ducted air conditioning. A ducted system can cool your entire home via its network of ducts. The ducts are hidden in the wall and only discreet wall panels are visible. A “set it and forget it” system, all you have to do is set the thermostat to the desired temperature and your house is always at the perfect temperature. If you pay extra, you can get reverse cycle air conditioning to heat and cool your home. For even greater control, you can get a zone system that allows you to air condition as many or few rooms at a time as you like.

Ducted air conditioning systems are more expensive to buy and install, but their running costs can be offset over time. Getting the right system from a reputable air conditioning installer can help reduce running costs.

Split Systems

A split system is designed for one room only. A single unit is therefore less expensive to buy and have installed, though this will depend on how many rooms they are installed in. Because they have lower energy demands, running costs on split systems are generally lower than ducted air con running costs.

The two most frequently cited disadvantages of split systems are their appearance and limitations. The compressor is fairly big and has to be located outside the house. This can detract from the appearance of the house if the unit has to be located in a prominent position. Although a split system is cheaper than a ducted system, it can only cool a single room. If you want to have air conditioning in the living room, bedrooms and other rooms, you have to buy air conditioners for each room.

At first glance, ducted air conditioning seems like a better solution if you want to air condition your entire house. However, many homeowners have chosen split systems instead and prefer them, saying they offer some hidden advantages:

• Buying a split system is more affordable because you can add on to the system as your budget allows.
• If one unit requires repair, the others continue working and repair costs are lower.
• Replacement costs are lower.
• Running costs are lower because split systems are used only when and where needed.

Whole Home Cooling

If you want discreet air conditioning for your entire house and your budget allows, a ducted zone system is probably the best choice for you. If you only need air conditioning for one room or don’t mind having a few compressors located outside the house, you might prefer a split system. In either case, buy an air conditioner with the right capacity for the space you’re cooling and look for one with a high Energy Star rating.  Then you’ll know you’re getting the most out of every kilowatt of energy your air con uses.