Trane Gas Furnace Efficiency FactorsTrane Gas Furnace Efficiency Factors – This is a Trane gas furnace. It is also called a Trane 90 plus gas furnace because it offers efficiency levels up to 90 percent plus AFUE (rating). Gas or oil furnaces generally cannot achieve efficiency at 100% because of impurities in the fuel including moisture. This is the reason why no fossil fuel furnace sold has a rating of up to 100%. This biggest impurity in many fuels is moisture which is difficult to remove because it is in the distribution and storage places where the fuel is distributed and stored. If these impurities were removed from the fuels before they were introduced to the furnace the cost of the fuel would be much higher and the cost to benefit ratio would not be effective.

Trane Gas Furnace Efficiency Factors – Additional Efficiency Factors

Fuel purity cannot be overcome without costly and excessive filtering that makes the savings factor useless. Whether it is a Trane gas furnace or a Goodman gas furnace this factor cannot be overcome. The fuel you buy from the gas company through a pipeline is what it is. There are other factors you can do to make sure you get the most out of the efficiency of the HVAC system. External factors to the HVAC system refer to your home. The windows and doors. Infiltration and exfiltration factors must be taken into account when looking at efficiency factors is important. Infiltration is outside air coming into the structure.

Exfiltration is inside air making its way out of the structure. This all has to do with insulting factors for the structure. The tighter the house the more efficiency you will save for heating and cooling. Within the HVAC system, there are also efficiency factors not related to the equipment. In this case, it’s a gas furnace or the heating system we are discussing. The external factor from the gas furnace itself is the ductwork.

Trane Gas Furnace Efficiency Factors | Additional Efficiency Considerations

You can have a 90 plus gas furnace and get efficiency but if your ductwork is bad or your house has is drafty windows and doors with bad insulation in the walls you will not gain so much as far as efficiency is concerned. Of course, it should be better than the older furnace but to increase efficiency for the whole system take care of other factors in addition to getting the new high efficient furnace. This is a good reason before you have a high-efficiency gas furnace installed that you look at the big picture and have an effective plan in place to fix drafty windows and doors and add insulation to your home or business.

Overall Factors/Evaluation | Trane Gas Furnace Efficiency Factors

It is also a good reason to do a complete evaluation of the entire HVAC system including the ductwork. Leaking ductwork will cause you to lose the efficiency of the whole system because the conditioned or heated air from the high-efficiency furnace is not being delivered to the space where it is needed. Instead, it is wasted in the space where the ductwork is located. The conditioned air should be delivered into the space and not in the attic or under the house. Give serious consideration to these factors and you will not regret it especially when you the gas or electric bill.


95% Plus AFUE Gas Furnace


Good Tight/Sealed Duct Work


Efficient Doors and Windows


Great Efficiency/Comfortable with Low Gas Bill


Low AFUE Furnace


Bad Leaky Duct Work


Leaky Doors & Windows


Cold/Uncomfortable with High Gas Bill

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High Performance HVACTrane Gas Furnace Efficiency Factors

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