Furnace Replacement & Installation

Thermo Pride oil furnace installed beside a Bosch heat pump air handler by Unity Heating & Air Conditioning in the Lehigh Valley

Furnace Replacement and Installation by Unity HVAC

Sized to your house, not the old nameplate. Installed and tested by the owner.

Most furnace replacements I do start the same way: a gas or oil furnace from the 1990s or 2000s that has needed two big repairs in two winters, or one that quit on the first cold night. I’m Tyler Furbacher, owner of Unity Heating & Air Conditioning in Macungie, and I install new furnaces across Allentown, Emmaus, Whitehall, Bethlehem, Breinigsville and the rest of the Lehigh Valley.

A furnace replacement isn’t a box swap. The new furnace is sized from a room-by-room load calculation on your actual house at the local winter design temperature. On many older houses that comes out smaller than the furnace coming out, which may have run oversized for decades and short cycled the whole time.

Free, no-obligation assessment: call or text (267) 644-9516.

What a furnace replacement includes

Every new furnace I put in gets the same checks, because most comfort and noise problems with new equipment come from skipping one of them:

Room-by-room load calculation
Duct static pressure measured on the running system
Venting and combustion air checked for the new furnace
Matched AC coil when central air rides on the furnace
Condensate drain or pump for condensing furnaces
Thermostat set up and explained
Permit where the township requires one
Startup combustion test and removal of the old furnace

Choosing a new furnace

  • Natural gas. The choice is between an 80% furnace that vents up the existing chimney or a 95%+ condensing furnace that vents out the side wall with plastic pipe. Federal efficiency rules move nearly all new gas furnaces to condensing models starting in late 2028, and I price both so you can see the difference. Gas equipment is covered in more detail on the gas and propane page.
  • Propane. The same furnaces as natural gas, set up for propane. With propane prices where they are, it’s worth comparing against a heat pump.
  • Oil. An oil furnace can be replaced with a new oil furnace, or with a heat pump that keeps the oil furnace as backup for the coldest nights. The Oil Savings Estimator shows that math for your house, and the oil heating page covers tanks and burners.
  • A heat pump instead, or dual fuel. For electric-heat and propane homes a cold-climate heat pump often costs less to run than a furnace, and dual fuel, a heat pump paired with a gas furnace, is the other common answer. Both are on the heat pump page.

Signs it’s time for a new furnace

A furnace doesn’t have to be dead to be done. These are the signs that push a repair call toward a replacement:

When replacement makes sense:

Age

Most furnaces last 15 to 20 years. Past that, repairs get more frequent and parts harder to find.

Repeat repairs

A second major repair in two winters usually means the money is better spent on a new furnace.

Cracked heat exchanger

A crack can leak carbon monoxide into the air you breathe. Replacing the heat exchanger alone costs a large share of a new furnace.

Rising fuel bills

An older furnace burns more gas or oil for the same heat as it wears and drifts out of adjustment.

Uneven heat or noise

Cold rooms, long run times and banging or rumbling often trace back to an oversized or failing furnace.

Failed combustion test

An oil furnace that can’t burn clean after cleaning and adjustment is near the end.

Thermo Pride oil furnace installed beside a Bosch heat pump air handler by Unity Heating & Air Conditioning in the Lehigh Valley

How a furnace replacement goes

You deal with me from the first visit to the startup test.

Step by step:

  • Assessment: I measure the house, check the ducts, venting and gas or oil supply, and ask what bothers you about the current system
  • Options in writing: one or two furnaces that fit, with prices, and what each one changes
  • Install day: most like-for-like furnace swaps take one day; switching fuels or changing venting or ductwork can add a day
  • Startup: combustion test, temperature rise and static pressure checked against the manufacturer’s numbers
  • Walkthrough: thermostat, filter changes and what to watch for

Furnace Replacement Questions

How long does a furnace replacement take?

Most like-for-like furnace swaps take one day. Switching fuels, moving the furnace, or adding new venting or ductwork can add a day.

What size furnace do I need?

It depends on your house, not on the old furnace’s nameplate. I size it from a room-by-room load calculation, and on older Lehigh Valley houses the right furnace is often smaller than the one coming out.

Do I have to buy a 95% condensing gas furnace?

Not yet. Federal efficiency rules require nearly all new gas furnaces to be condensing models starting in late 2028. Until then 80% furnaces are still sold, and whether condensing pays off depends on your venting and how much gas you use. I’ll price both.

Can I replace my oil furnace with gas or a heat pump?

Yes. If natural gas is available on your street, converting is an option. Otherwise a heat pump that keeps the oil furnace as backup is common. The Oil Savings Estimator on this site shows the math for your house.

Do you also install central air with the furnace?

Yes. When central air rides on the furnace, the AC coil is matched to the new furnace, and if the air conditioner is near the end too, replacing both at once is usually cheaper than two separate jobs.

Which towns do you install furnaces in?

Macungie, Alburtis, Emmaus, Allentown, Whitehall, Bethlehem, Easton, Breinigsville, Trexlertown, Wescosville, Fogelsville, Ancient Oaks, Upper and Lower Macungie, Coopersburg, Center Valley and Quakertown.

Get a Furnace Replacement Quote

Call or text for a free, no-obligation assessment. You’ll get a straight answer on repair versus replacement, options that fit your house and prices in writing.

Phone Service

(267) 644-9516

24/7 Emergency Service Available

Email Contact

info@unityhvac.com

Or use the contact form

Free Consultation

No-Obligation Assessment

Honest Advice & Fair Pricing

Where I install furnaces

Furnace replacement and installation runs out of the shop in Macungie: Allentown, Whitehall, Emmaus, Macungie, Alburtis, Breinigsville, Trexlertown, Wescosville, Ancient Oaks, Upper Macungie, Lower Macungie, Bethlehem, Easton, Coopersburg, Center Valley and Quakertown. Replacing the whole system, furnace, air conditioning and ducts together, is covered on the full system replacement page, and repairs on the furnace repair page.

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