Gas Furnace Replacement & Installations

Knox, IN Furnace Services


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McGrath Refrigerationstarstarstarstarstar4.9 / 5

70 Total Reviews 574-772-3575$2520 S US 35, Knox IN

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Third generation McGrath Refrigeration Heating & Air Conditioning has over fifty years of experience helping Starke, IN area homeowners and businesses with their winter comfort needs. By far the most popular heat system in Starke and Marshall Counties, Indiana, are ducted gas furnaces. If you’re building a new home, or if your existing Knox, IN area natural gas furnace is more than 10 years old you might want to learn more about a new efficient and reliable gas furnace from McGrath Refrigeration.

  • Our installers are factory trained and highly skilled
  • We will design your new system to heat your home perfectly and efficiently
  • Questions about what furnace would be best? Call us today!

Natural Gas Furnaces

We feature Armstrong and Ducane™ gas furnaces. Armstrong offers award winning technology while Ducane™ offers affordable gas furnace choices for a wide variety of residential or light commercial applications.

McGrath Refrigeration Featured Gas Furnace Models

Armstrong Air Furnace A97MV

A97MV Pro Series™
Armstrong - Best

  • Efficiency AFUE  97%
  • Combustion Type  Modulating
  • Controls  Comfort Sync®
  • Blower Motor  Variable
  • Nipsco Rebate**  $200
Furnace Specs
Armstrong Air Furnace A97MV

A962V Pro Series™
Armstrong - Better

  • Efficiency AFUE  96%
  • Combustion Type  2-Stage
  • Controls  Comfort Sync®
  • Blower Motor  Variable
  • Nipsco Rebate**  $0
Furnace Specs
Armstrong Air Furnace A97MV

A951E Standard
Armstrong - Good

  • Efficiency AFUE  95%
  • Combustion Type  1-Stage
  • Controls  24-VAC
  • Blower Motor  Constant Torque
  • Nipsco Rebate**  $0
Furnace Specs
Armstrong Air Furnace A97MV

A802V Pro Series™
Armstrong - Best 80%

  • Efficiency AFUE  80%
  • Combustion Type  2-Stage
  • Controls  Comfort Sync®
  • Blower Motor  Variable
  • Nipsco Rebate**  $0
Furnace Specs
Ducane Furnace 96G2V

95G1E
Ducane™- Best

  • Efficiency AFUE  96%
  • Combustion Type  2-Stage
  • Controls  24 Volt
  • Blower Motor  Variable
  • Nipsco Rebate**  $200
Furnace Specs
Ducane Furnace 92G1E

92G1E
Ducane™ - Better

  • Efficiency AFUE  92%
  • Combustion Type  1-Stage
  • Controls  24-VAC
  • Blower Motor  Constant Torque
  • Nipsco Rebate**  $0
Furnace Specs
**Nipsco is our local Natural gas supplier. They offer attractive rebates for the installation of Armstrong and Ducane™ gas furnaces. Click here for details.
Call Mcgrath for furnace repair services today!

Gas Furnace Repair Service

If your gas furnace requires emergency service or scheduled furnace maintenance we're here to help. We services all brands, and stock an extensive replacement parts inventory. Click here for more information about our heating repair services.

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Call Mcgrath for furnace repair services today!
Call Mcgrath for furnace repair services today!

About McGrath Refrigeration Heating & Air Conditioning

Now in our third generation, we have been family owned and based in Knox, IN since 1967.

We are an Armstrong Comfort Team dealer. This reflects our long term commitment to technology, training, and customer service.

All of our heating technicians are licensed and insured. We have decades of experience meeting the unique challenges posed by our Starke County, IN winters.

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Gas Furnace Features:

Armstrong and Ducane™ furnaces support a broad range of applications. Gas furnace features include:

  • Features Exclusively available on Armstrong ProSeries™ gas Furnaces:
    • ComfortSync®: Sophisticated furnace operation and control with optional Comfort Sync® thermostat. With our ComfortSync® App you can access your heating system from anywhere through your Apple or Android Smartphone.
    • Top Efficiency Armstrong Pro Series™ gas furnaces offer efficiencies as high as 97% AFUE.
    • Modulating Operation: Traditionally gas furnaces are single stage and are either on at 100% output, or off. Modulating gas furnaces are available with fully modulating operation and variable speed fan motors for the ultimate in comfort and efficiency.
  • Airflow Configuration: Armstrong and AirEase™ furnaces are available in an upflow, downflow, or horizontal airflow.
  • System Efficiency: Older gas furnaces in the Knox, IN area have seasonal efficiencies (AFUE) as low as 60%. Modern Armstrong and Ducane™ gas furnace range in efficiencies from 80% to 97%.
    • Standard Efficiency Models: If you are replacing an existing gas furnace, there is a good chance that it is vented through a B-Vent or masonry chimney. As a system replacement, the easiest retrofit for a new Armstrong or Ducane™ gas furnace would be an 80% AFUE model.
    • Condensing Furnaces (90%+ AFUE) have much lower flue gas temperatures and can use alternative PVC or PBS venting, and can terminate on a sidewall or through the roof. It CANNOT vent into a conventional chimney. In addition, condensation (slightly acidic water) is produced as a byproduct of combustion and will need to be considered.
  • Staging: Gas furnaces traditionally fire at their full rated capacity, and then cycle off when the thermostat is satisfied.
    • Better: Two stage operation has become available for a couple of decades. In milder weather the gas furnace fires at first stage, typically about 60% of its full rated capacity. This provides quieter operation and more consistent comfort.
    • Best: Full modulating operation: The furnace fires over a broad range of its rated capacity, so the furnace output closely matches the system demands at any time. This provides the ultimate in efficiency and systems comfort.
  • System Blower Motor: A single stage PSC based blower motor is traditional. It has only a single speed, and is relatively inefficient electrically.
    • Better: Constant Torque Motors: A higher efficiency, brushless DC motors that are designed to provide a given rate of airflow (CFM) even when operating conditions like static pressure change.
    • Best: ECM Variable Speed Motors: An ECM (electronically commutated motor) can provide a broad range of airflows based on system requirements for better comfort and air quality while using less energy than other motor types.
  • Thermostats and Controls: In the past, traditional furnace controls operated on a single stage mercury based thermostat with 24 VAC control voltage.
    • Better: 24 VAC Two stage electronic (mercury free) thermostat.
    • Smart Thermostats with or without Apple or Android Apps.
  • IAQ: Indoor Air Quality is increasingly important. More advanced filtration and sterilization, combined with longer, more efficient airflow will result in a healthier, and more comfortable indoor environment. Click here for more detailed IAQ information.
    • Better: Two stage furnaces that can operate at lower capacity during milder weather.
    • Best: Modulating furnaces with variable speed blowers.

Our factory trained, licensed and experienced heating technicians will evaluate your application, carefully determine the proper furnace size, and help you decide what Armstrong or Ducane® furnace will meet the needs of your application and budget. We'll provide a detailed evaluation of your needs and a complete quote for the services we're proposing. Then, with your approval, thats exactly what we'll do.

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