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  • What is a modulating or two-stage furnace?
    Modulating Furnace: Most furnaces are either “off”, providing no heat, or “on” at full capacity, with the burner and blower operating at 100%. This causes the temperature in your house to go up and down by several degrees – affecting both your comfort and your energy bills. Furnaces are designed to keep your home warm on the coldest of days. But in most cases, those days account for only 2-1/2 percent of the heating season. The rest of the time, you furnace is providing more heat than is needed to satisfy your comfort requirements. Modulating furnaces solve this problem by “modulating” between different capacities (40-100%), depending upon the comfort requirements of the homeowner and the temperature outside. This results in lower operating costs, quieter operation and much more even temperatures throughout the home. It’s like having a separate furnace to handle the unique heating requirements of each day – all in one unit! Check out the Rheem Modulating Furnace with Contour Comfort Control – the only truly modulating gas furnace in the world! Two Stage Furnace: A two-stage furnace has the same concept in mind as a modulating furnace. The difference lies in the fact that while a modulating furnace can operate at any capacity between 40% and 100%, a two-stage furnace operates on a low-stage and a high-stage. The low and high stages have preset BTU outputs. On most days, the furnace will operate at its first stage to only provide the heat you need to stay comfortable. On those very coldest days of the year, this furnace will ramp up to its second stage and give the full BTU output of the furnace to keep satisfying the heating requirements of the home. It’s basically like having two furnaces in one – one for warmer days and one for the very coldest.
  • What do rating numbers mean?
    The U.S. government requires an efficiency rating of all air conditioning and heating equipment. The rating reflects the percentage of energy used efficiently, with a high rating indicating high-efficiency. The next two topics address this issue in greater detail.
  • What is a SEER?
    There are special names for the efficiency ratings of various types of equipment. Air conditioning equipment is rated by the Seasonal Energy Efficiency Rating, or SEER. The higher the SEER rating, the more efficient the unit.
  • What does HSPF stand for?
    There are special names for the efficiency ratings of varying types of equipment. Heat pump equipment in the heating mode is rated by the Heating Seasonal Performance Factor, or HSPF. The higher the HSPF rating, the more efficient the unit.
  • What does AFUE stand for?
    There are special names for the efficiency ratings of various types of equipment. Gas furnaces are rated according to their Annual Fuel Utilization Efficiency, or AFUE. The higher the AFUE rating, the more efficient the unit.
  • Should outdoor units be covered in winter?
    No. Rheem heat pumps operate year-round and should never be covered. Similarly, air conditioners that operate seasonally are built to withstand an outdoor environment and should not be covered.
  • Should a thermostat be set to "auto" or "on"?"
    Preferably auto. That way, the fan operates only when the temperature requires it. This is the most used and the most efficient setting. However, there are advantages to using the "on" setting. Air is constantly filtered through the unit's air filter, and the constantly circulating air results in an even temperature throughout the house.
  • Can shrubs or flowers be planted around an outdoor unit?
    Yes. However, we recommend that plants be no closer than 18 inches to the unit. This allows for plenty of room for air circulation in and out of the unit. Without this room for air circulation, the unit could overheat, resulting in a premature need for service
  • If an outdoor unit needs replacing, should the indoor unit be replaced too?"
    Yes. Rheem air conditioning and heating units are designed to operate as a complete, matched system. The efficiency rating is based on the entire system. Replacing the entire system ensures the system will be reliable and efficient.
  • How do I know what size unit our house needs?
    Contact your Rheem Pro Partner Contractor. He will consider many factors before making a recommendation. Factors like … size of the house, climate, the number and type of windows installed, insulation, and even the number of people living in the house.
  • What is the difference between a split system and a package unit?
    A split system uses indoor and outdoor components to provide a complete home comfort system. A package unit or self-contained unit requires no external coils, air handlers, or heating units.

Here are some of the questions we have been asked about our Rheem products and services. If you have any other questions that have not been answered below, please Contact Us  and we will be glad to answer them for you.

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