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Single Stage vs Two Stage Furnace

single stage vs two stage furnace

Your home comfort greatly depends on your furnace’s performance, so it is vital you ensure the new unit heats your home efficiently to save on energy costs. When choosing a new furnace one of the main decisions you will make is whether you want a single stage or two stage furnace. In this article we discuss what the differences are so you have the knowledge to choose which one is best for you.

What is a Single Stage Furnace?

Single stage furnaces only have two settings: on and off. They will heat your home at 100% full capacity power whenever the furnace is on until the set temperature is reached. A single stage furnace contains a fixed gas valve and single speed blower motor. It achieves full capacity by running the fan at full speed and opening the gas valve all the way to deliver the most heat possible to your home. This means that even if your home only needs a little bit of heat it will run at full blast.

Single Stage Furnace Pros

Compared to two stage furnaces a single stage furnace is the least expensive type when considering furnace replacement. Since they have fewer complex parts and straightforward operation, they are easier to maintain and are often less costly to repair.

Single Stage Furnace Cons

Since a single stage furnace will run at full power whenever it is on, the areas near the vents will warm up quickly. This will cause your thermostat to think the whole house has reached the desired temperature and shut the furnace off prematurely. This will result in warm and cold spots around your home. To prevent uneven temperatures throughout the home, you may be tempted to raise the temperature resulting in higher heating costs. Single stage systems may also be noisier to operate.

What is a Two Stage Furnace?

A two stage furnace has a third setting in comparison to a single stage furnace. The system can be on low, high or turned off. The furnace will begin in the lower setting and switch to the higher one if necessary. In low mode, two-stage furnaces uses a three-way gas valve to regulate how much gas flows into the furnace simultaneously. The gas valve is always either fully open or fully closed in a single-stage furnace. The addition of the low setting provides added energy efficiency with more stable temperatures in your home. On the low setting a two stage furnace only uses about 60%- 70% of its total capacity.

Two Stage Furnace Pros

The main advantage of a two stage furnace is more even heat distribution, resulting in more stable temperatures. The low setting option of a two stage furnace can contribute to better indoor air quality as well. Since the furnace is running for a longer period, there is better air circulation through the filter, removing pollutants and other allergens. Also, when running on low, the furnace will not make as much noise as a single stage system. Lastly, it is longer lasting equipment since it is not always running at 100% capacity it reduces the strain on its components.

Two Stage Furnace Cons

While two stage furnaces are more efficient, they do come with a higher upfront cost. On average they will also cost more to repair and maintain since they are a more intricate complicated system, with more expensive parts. Keep in mind you are more likely to benefit from the long term benefits of lower energy bills of a two stage system if you live in a multi-story home in which you intend to live in for several years.

Single Stage vs Two Stage Furnace

The right furnace model will depend on several factors: budget, energy efficiency, and your comfort needs. Single stage furnaces will have a less costly furnace replacement compared to two stage furnaces. However, in the long run they will cost more to run since they are less efficient. For long term savings, consider how long you intend to live in the home. Consider the heating needs of you and your home, and if you value consistent indoor temperatures, and a quieter operation consider the two stage system.

Contact LA Construction, Heating and Air

Taking into consideration that a gas furnace is a 15-20 year investment, understanding the characteristics of each type for furnace will give you the knowledge to purchase the heating equipment most ideal for you and your home. At LA Construction, Heating and Air we specialize in furnace installation and can help you choose which furnace better fit your needs. We work with all brands and types. Contact us online today or give us a call for furnace replacement. We also offer indoor air quality solutions, furnace repair and furnace maintenance. We are here to help you stay warm and cozy this winter season.

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We provide expert heating installation and furnace replacement services. Our certified technicians perform a thorough load calculation to recommend the best and most energy-efficient furnace installation. We manage every detail of your new heating system installation, from start to finish, to deliver a high-quality, reliable, and professional heating installation service.
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When your heating fails, our team provides prompt and professional heating repair and furnace repair. We are experts at diagnosing and fixing a wide range of issues. We offer fast emergency heating repair to minimize your business's downtime, delivering reliable heating service that ensures your system runs safely and efficiently all winter. Learn more

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Whether you're at home or at work, your health and comfort can be affected by poor air quality. And, the air quality is affected by the air temperature, the humidity, the quality of ventilation and any contaminants or irritants like indoor pets, pollen, dust mites, cleaning products, lead, Formaldehyde and Asbestos, Poor Air Flow, mildew and mold. Poor air quality can cause more than slight discomfort - much more!

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Maintenance

As Benjamin Franklin said, an ounce of prevention is worth a pound of cure. Same idea applies to your central heater and air conditioner maintenance.Think of it as an oil change for your auto, which improves your car's engine performance, maximizes your gas millage and minimized down time by avoiding unnecessary repairs.

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