When buying a new furnace, it's easy to think that a bigger furnace will give you faster and more efficient heat for your home. But unless your previous furnace was undersized from the start, going with a bigger furnace actually gives you the opposite performance. Only a furnace that's precisely tailored to your home's size and heating
Here are three good reasons why installing an oversized furnace is never the right choice for your home.
1. You'll Lose Consistent Comfort
If you have a furnace that struggles to heat your home in an even and consistent manner, you might be tempted to choose a new furnace that has a bit more heating capacity than your home actually needs. However, installing an oversized furnace won't guarantee consistent heat throughout your home. In fact, the excess capacity can make your heating problems worse.
If you have a hard time getting certain rooms in your home warmed up, the underlying problem usually involves poor airflow balance. An oversized furnace will only make the issue worse – cold rooms will remain cold while rooms that get warmer than expected will now become uncomfortably hot. Thermostat placement can also prevent certain rooms from warming up properly.
2. You'll Also Lose Efficiency
Modern furnaces are designed to run as efficiently as possible, but only when they run correctly. A typical furnace will enter an initial warm-up phase and steadily reach the desired temperature within 10 to 15 minutes of operation. An oversized furnace will reach that temperature in record time – usually within 5 to 6 minutes – and then shut off.
The problem is this happens during the least efficient phase of the furnace's operation – the warm-up phase. Adding insult to injury, the furnace will cycle on again and again just to maintain those desired temperatures, sometimes even before the furnace reaches its proper temperature. You'll end up paying more in energy costs than you would with a properly sized furnace.
3. You'll Get Less Life from Your Unit
Remember the part about the oversized furnace cycling on and off repeatedly? It's a problem known as "short cycling" and it can wreck your furnace if left unchecked. Furnaces weren't designed to start up and shut down rapidly. Under short cycling, internal components are subject to extreme stresses and unusual wear, moving the entire unit close to a sudden breakdown.
An oversized furnace will fail sooner and be more expensive to replace than simply using a properly sized furnace. Right-sizing your new furnace will help it last longer while giving your home greater comfort and efficiency. For more information on your particular needs, check with a furnace installation professional.