Furnace Installation: How an Oversized Furnace Causes Short Cycling

Furnace Repair Technician Tips

To meet the needs of different environments and lifestyles, furnaces come in different sizes. Many homeowners will choose to get a bigger unit, believing in the notion that it will perform better. Installing an oversized furnace, however, can lead to multiple problems, including short cycling. If you are experiencing a noisy AC operation and your utility bills are steadily increasing, it may be time to replace your inefficient furnace. If your current device is not working optimally, look for professional HVAC companies in Toronto to make a sound installation for you.

Heating Cycles

When a furnace is too large for the room it is installed in, it experiences very fast heating cycles, putting it through quick wear and tear and increasing the chances of a breakdown of your system. This is because set temperatures are achieved rapidly, causing the furnace to shut down. Once the heating components are dramatically increased, you will require frequent repairs and maintenance. The proper size of a furnace ensures that the system operates in an efficient burn stage throughout the day.

Inefficiency in Operation

Due to constant stop and start mode that tends to use more fuel, heating costs increase and the furnace is also not able to operate at the set efficiency levels. There is no way to correct such a problem, which is often caused by an oversized system, but to have furnace installation professionals replace it. When a furnace fires up, it becomes ineffective and fails to reach its peak efficiency until the air leaving it reaches a steady value. Understand that an oversized furnace operates more on the warming up phase, and once it reaches a steady temperature, it shuts off again.

With such a system, heat tends to blast for short periods, causing the room to feel cold or hot during the heating cycle. Some rooms may be warmer while others may fail to receive equal amounts of heat. If the thermostat heats up too fast, the furnace may not get the chance to run enough and heat your home. Professionals will have to calculate your current heating space and will not make assumptions that you will require a larger furnace in the future. Note that the IFUE efficiency and BTU capacity ratings will not be accurate if incorrect calculations of the needed furnace are made, making it impossible to achieve the desired HVAC performance.


Emergency heating system replacement policy: Furnace replacement, Home Performance
Measure Guideline: High-Efficiency Natural Gas Furnaces, National Renewable Energy Laboratory

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