Furnace Installation & Replacement in Brooklyn
Forced-air gas furnace replacement and new installs for brownstones, row houses, and two-families — sized to the house, vented right, quoted in writing.
Repair or Replace? Where the Line Usually Falls
This page is for people whose furnace is at, or near, the end. If yours simply stopped heating this week, start with furnace repair in Brooklyn — most no-heat calls are a single failed part, and we'd rather fix a sound furnace than sell you a new one. Replacement is the right answer in a narrower set of situations, and we'll tell you honestly which one you're in after a diagnosis.
Repair still makes sense when
- One failed part — ignitor, flame sensor, capacitor, pressure switch, blower motor
- The heat exchanger is sound and the cabinet is dry
- The furnace is under roughly 15 years old
- It has run reliably until this one failure
Replacement is probably right when
- The heat exchanger is cracked or rusted through — that is a safety issue, not a repair
- The furnace is past 20 years and has needed a repair every winter
- Parts for the model are discontinued or weeks away
- It was never sized right — short cycling, cold rooms, or a unit far bigger than the house needs
- You're replacing the central AC anyway and want the blower and coil matched to it
- Fuel bills keep climbing on an old 65–80% unit while the house feels no warmer
Sizing: A Load Calculation, Not the Old Nameplate
The most common furnace mistake in Brooklyn is copying the BTU rating off the old unit. Furnaces installed in the 1990s and 2000s were routinely oversized, and an oversized furnace short cycles: it blasts the thermostat satisfied in a few minutes, shuts off before the far rooms warm up, and repeats that all night. The parlor floor is warm, the top floor is cold, and the fuel bill is high anyway.
We size from a load calculation for your building — floor area, insulation, window area and exposure, air leakage, and how the floors are zoned. Brownstones and row houses share masonry party walls with the neighbors, so their heat loss is nothing like a detached house of the same size. A three-story brownstone with a finished garden level, a two-family with a furnace per unit, and a wood-frame house in Bushwick each come out differently, and the furnace should match the number, not the habit.
Ductwork, Venting, and Gas: What Decides the Job
Ductwork. Most Brooklyn forced-air systems were added to a house that never had ducts, so returns are undersized and supply runs are long. We measure static pressure across the existing system before choosing a furnace. A modern variable-speed blower pushed against restrictive ducts runs loud, trips limits, and wears out early. Sometimes the fix is a second return; sometimes it's a plenum rebuild; sometimes the ducts are fine and just need a proper filter rack. Whichever it is goes in the quote, not in a change order.
Venting. An 80% furnace vents hot flue gas into a chimney or metal flue, and an old masonry chimney usually needs a liner sized for the new furnace. A 95%+ condensing furnace vents cool exhaust through PVC to an outside wall and drains condensate. In a mid-block row house with no easy path to an exterior wall, venting can decide which furnace makes sense — we look at that before we quote, not after.
Gas and electrical. The gas line is checked for size and pressure at the appliance, especially where it's shared with a stove or a water heater. High-efficiency furnaces need a condensate drain, and every furnace gets a proper disconnect. On start-up we set manifold gas pressure, verify temperature rise, and check combustion — the furnace leaves running the way the manufacturer intended, not just running.
Efficiency, Staging, and Controls
Two numbers matter. AFUE is how much of the gas becomes heat — 80% for a standard furnace, 95% and up for a condensing furnace. Staging is how the furnace runs: single-stage furnaces are on or off; two-stage and modulating furnaces run at a lower rate most of the time, which means longer, quieter, more even cycles in a tall narrow house. A variable-speed (ECM) blower also cuts the electricity a furnace uses and pairs better with central AC.
Controls decide whether you get what you paid for. A two-stage furnace on a one-stage thermostat runs as a one-stage furnace. Many older Brooklyn thermostats have no C-wire, which most smart thermostats need. We check the wiring at both ends and include the right thermostat in the quote — see smart thermostat installation if you want app control with the new furnace. Utility rebates on high-efficiency equipment change year to year; we'll tell you what applies at the time of the quote.
What's in a Furnace Installation Quote
- The exact furnace model, BTU input, efficiency rating, and staging
- Removal and disposal of the old furnace
- Venting — chimney liner or new PVC vent run, whichever the furnace and the house need
- Gas connection, shut-off, and any pipe-size correction at the appliance
- Electrical connection and the furnace disconnect
- Condensate drain and pump on high-efficiency models
- Thermostat check, and a new thermostat if the old one can't run the new furnace
- Duct transitions, plenum work, and a filter rack that fits a real filter
- Permits and inspection where the job requires them
- Start-up: gas pressure set, temperature rise verified, combustion checked, blower speed set
- Labor warranty on the installation, plus the manufacturer's equipment warranty registered in your name
Written, itemized, and priced before any work. No prices are published here because the venting, ducts, and access of your building change the number more than the furnace does.
What Makes an Install More Complex
- Cellar access — narrow stairs, low headroom, and a furnace that has to come apart to get out
- Chimney condition — an unlined or oversized masonry chimney needs a liner before an 80% furnace can vent into it
- No good return-air path — common in row houses where ducts were added later
- Old gas piping that is undersized for a larger burner, or shared with a boiler or stove
- Suspect duct wrap or insulation on older systems, which has to be handled by an abatement contractor first
- Co-op and condo paperwork — insurance certificates and board sign-off before work starts
- Two-family and multi-family zoning — one furnace per unit, separate thermostats, separate venting
Worth Discussing: Heat Pumps and Hybrid Systems
If the central AC is due at the same time as the furnace, a cold-climate heat pump paired with a gas furnace — a hybrid or dual-fuel setup — is worth a conversation. The heat pump carries the heating on most days and the furnace takes over on the coldest ones. For houses without ducts, or where the furnace only served one floor anyway, ductless heat pumps can replace both heating and cooling. We'll show you the trade-offs with real numbers for your building rather than a sales pitch either way; see heat pump installation in Brooklyn for how those systems perform here.
How a Furnace Replacement Goes
- 01
Walkthrough
We look at the furnace, ducts, chimney or vent path, gas line, thermostat, and access, and we run the load calculation.
- 02
Written quote
Equipment options at more than one price point, everything included spelled out, and a realistic timeline.
- 03
Install day
Old furnace out and disposed of, new furnace set, venting and connections made, ducts transitioned, drop cloths down and the cellar left clean.
- 04
Start-up and walkthrough
Gas pressure, temperature rise, combustion and blower speed set and recorded; thermostat programmed; we show you the filter, the switch, and what normal sounds like.
- 05
Paperwork
Equipment warranty registered in your name, inspection scheduled where required, and the written start-up numbers for your records.
Forced-air furnaces only. Hot-water boilers we repair; we do not install or replace them.
Why Brooklyn Calls Us for Furnace Installs
- Load calculation on every install — the furnace fits the house
- Venting and ductwork inspected before the quote, not discovered after
- Brownstones, row houses, two-families, and walk-ups are our everyday work
- Written, itemized quote with options — no pressure to pick the biggest one
- Labor warranty on the installation; equipment warranty registered for you
- EPA-certified and insured — insurance certificates for co-op and condo boards
What Brooklyn Says About Our Heating Work
4.8 stars from 79+ verified reviews
Furnace Installation Brooklyn — FAQs
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View pageReplacing a Furnace? Get a Written Quote.
We measure, size, and price it in writing before any work. Financing available on qualifying installs.