What is the Difference Between Single-Stage, Two-Stage, and Modulating Furnaces?

24 / 7 Emergency Service Available. Call Us Now: 1.844.894.6832

What is the Difference Between Single-Stage, Two-Stage, and Modulating Furnaces?

Posted On: January 8, 2020

What is the Difference Between Single-Stage, Two-Stage, and Modulating Furnaces?

When you are looking around for a new furnace, you will come across three different types: single-stage, two-stage and modulating. You may probably ask, what are the differences between them, and which one is right for your home?

In this article, we will explain the differences between them and help you decide which furnace works best for you and your family.

Single-Stage Furnaces

Single-stage furnaces only have one setting, which is high heat. On a call for heat, they immediately start running at full capacity, no matter what the temperature is outside until the signal coming from the thermostat is turned off. These types of furnaces are best suited for budget-conscious consumers, so in the long run, the upfront cost savings are not realized.

Two-Stage Furnaces

A two-stage gas furnace has two settings, high fire and low fire, and here is how it works. Most of the time, on a typical heating cycle the furnace will start out running on low fire, consuming less gas and electricity, while at the same time providing heat and gaining inefficiency. After approximately 7- 10 minutes of operation, the furnace begins to operate very efficiently because it is fully warmed up. Then, it will jump up into high fire and finish out the heating cycle at full capacity. Control of the high and low burner timing are made by the installers, as part of a new furnace installation.

You could also control the 2 stage burner by using a 2 stage thermostat, the effect of either is similar. Two-stage furnaces are considered more energy-efficient than single-stage because they are not always running at a full heating capacity of the appliance and are often equipped with an ECM blower motor which will also save on your electricity costs.

Modulating Furnaces

Modulating gas furnaces are at the top end of the gas furnace spectrum and are considered to be the most energy-efficient of the three. But, at an added price over two-stage or single-stage furnaces. Heating from a modulating furnace ramps up in increments to maintain a consistent temperature and the ductwork is always warmed up so there is a little efficiency lost during the warming up process.

When buying a modulating furnace you will almost always need to invest in a new thermostat controller specifically designed for this type of furnace in order to get the most out of it. Always ask your salesman about this option, as it is often not mentioned (due to the added cost of the new thermostat). If you are planning to stay in your home for the long-term, a modulating gas furnace may be the right fit for you.

When you want to buy a new furnace, you should always consult your local HVAC experts before making a decision. A trained HVAC technician can come to your home, go over your situation with you and help you decide which furnace best suits your home.

When you are ready for a new furnace, contact the Twintech experts! Our technicians are experienced and knowledgeable in all types of furnaces and HVAC systems.

For more information about our services, visit our website or give us a call at 1-844-894-6832. Contact Twintech today!