When Replacing your Old Furnace, Heat Pump, or Air Conditioner… Don’t Ignore Your Ducts

When Replacing your Old Furnace, Heat Pump, or Air Conditioner… Don’t Ignore Your Ducts

An investment in a new high efficiency heating and cooling system should save significantly on your utility bills. However, you will not save much if your existing ductwork is in bad shape.

A typical poor duct system really drags down the performance of new high efficient equipment. Many buyers of new equipment have ended up with little or no savings.

Compared to before, many also find:

  • Their home is less comfortable
  • There is more dust and summer humidity
  • Their new system is noisier

Don’t let your old ducts keep you from getting the high performance you are paying for.

To ensure your new equipment saves money and works properly, slow down and become an informed consumer. Have your duct system tested for leakage, correct sizing, and correct insulation levels.

Modern High Efficiency HVAC Equipment is Much More Sensitive to Bad Ducts

A weak duct system will lower the performance of new high efficiency equipment even more than it hurt the old unit. e main reason is the modern air-circulating blowers are more powerful. If your old duct system is leaky, the new higher pressures will accelerate the duct leakage. If your old ducts are restricted or undersized, the new blower motor will strain to overcome this and greatly increase electrical consumption and noise.

Many new units also achieve higher efficiency by having both a low and a high speed. Unfortunately, much of the efficiency gain is lost when connected to a bad duct system, as the longer run times lead to greater duct leakage, as well as greater energy loss through the duct insulation. is wastes money, and also increases indoor dust, summertime humidity, and wintertime dryness.

Buying new high efficiency heating and cooling equipment, and then hooking it up to the typical inefficient duct system, is like buying a super-fuel-efficient hybrid car and then driving it with a leak in the gas tank.

ductwork Belleville MI

“It does not make sense to install a new, energy-efficient heating and/ or air conditioning unit unless the duct system is also energy efficient.”

Pacific Gas and Electric Utility

“Even if you have the most efficient furnace and air conditioner known to man, if the ducts that funnel that precious hot air or cold air around your house are in bad shape, you’ll still lose way too much energy.”

Money Magazine

“Both DOE and EPA have done a lot of studies on the efficient of heating and cooling systems and we have found that over 70% are installed incorrectly to some degree or another … reducing the efficient of that system dramatically.

They may think they are buying a highly efficient EnergyStar SEER 14 cooling system and in fact, the operating efficient may be closer to 10 … and consequently, the homeowner is not getting what they paid for.”

Chandler Von Schrader, US EPA EnergyStar, Washington DC


Don’t forget about those leaky ducts. A system is only as good as the duct work its connected to. To optimize your system, you may be interested in Aeroseal. Areoseal is a duct sealing product that seals your ducts and helps improve you air conditioning system in four key areas: equipment performance, energy efficiency, improved indoor air quality, and dust control. Ask us about Aeroseal!

Air Doctors Heating and Cooling, LLC are a fully licensed and insured heating and air conditioning company that serves most Southeast Michigan municipalities. Our staff is fully certified and pre-screened to provide our customers with a safe and satisfying experience. With over 100 years of combined industry experience, we take pride in solving all of your comfort needs. We are a family-based business that has been providing quality service to our neighbors for over 40 years. Contact us today to get started.

Air Doctors employs NCI Certified Technicians.