Water-Heater EF: How It Factors Into Your Purchase - Glasco Heating & Air Conditioning
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Water-heater EF refers to the water-heater’s energy factor, which is based on the amount of hot water your water-heater produces per unit of fuel it consumes over a typical day. Your water-heater’s manual or the product literature provided by its manufacturer will typically provide your water-heater’s energy factor.

Energy-efficiency-conceptYour water-heater EF is calculated using three factors:

  • Recovery efficiency
  • Standby losses.
  • Cycling losses

The efficiency in which the heat from your water-heater’s energy source is transferred to the water determines its recovery efficiency. Standby losses refer to the heat that is lost hourly from the water stored in the water-heater’s tank, compared to the actual heat in the water. The heat that is lost as the water is circulated through inlet and outlet pipes and the water-heater tank is referred to as cycling losses.

The higher your water-heater EF, the more efficient it is, but a high EF doesn’t necessarily mean you’ll have lower annual operating costs. Operating costs depend largely on the fuel source used to heat your water. For this reason, you shouldn’t select a water-heater based solely on its EF. You should also consider size, fuel type, overall cost, demand in your home, and the water-heater’s first hour rating.

Your water-heater needs to meet your household’s hot water needs. If it’s too small or too large, then it’s probably not operating at optimum efficiency. Fuel type and its availability can limit your water-heater options. Compare the cost of the types of fuels available to you, and don’t forget to look into the cost of electricity as well.

Typically a water-heater’s first hour rating, also referred to as capacity, is listed on the EnergyGuide label or the product literature. The ideal rating should match your peak hour demand, or be within one to two gallons of that number.

If you’d like professional advice on the water-heater EF in your Connecticut home, contact Glasco Heating & Air Conditioning. We’ve been in business since 1994 and offer honesty and value to our customers.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems).  For more information about water-heater EF ratings and other HVAC topics, visit our website.

Glasco Heating & Air Conditioning services South Windsor, Connecticut and the surrounding areas.