Furnace Installation and Replacement in Delaware County, PA
Replacing a furnace in Delaware County is seldom a like-for-like swap, because what goes in is not the same machine as what comes out. A condensing furnace vents in plastic through a wall rather than up a chimney, makes acidic condensate that has to be drained, and moves air differently from the eighty percent unit it replaces. The quality of a replacement is decided by how those three differences get handled.
PJ MAC HVAC Service & Repair fits replacements across the county from 642 Harper Ave in Drexel Hill. Estimates for installation and replacement are free.
Sizing down is usually the right answer
Most furnaces coming out of these houses are larger than the house now needs. They were sized by rule of thumb decades ago, often before anyone insulated the attic or replaced the windows, and fitting the same size again preserves the same complaints: short fierce cycles, a wide gap between the rooms nearest the furnace and those furthest away, and a blower that never settles. A load calculation on the house as it stands usually points at something smaller, and a staged or modulating burner does more for how the house feels than any efficiency figure on the carton.
The chimney problem nobody mentions
This is the detail that catches people out in twins and rows. If the old furnace vented into a masonry chimney and the new one vents in plastic through the wall, the water heater is left on a flue sized for two appliances and now serving one. An oversized cold chimney does not draft well, and a water heater that cannot draft spills combustion products into the basement. An orphaned water heater is part of the furnace job, solved by lining the flue down to size or changing to a directly vented unit.
Where the new vent is allowed to end
On a house with a few feet between it and the next building, the sidewall termination is a design question rather than a formality. It has to keep clear of openable windows, doors, the property line, the intake on the same wall, and the ground, so drifted snow cannot bury it. Get it wrong and the furnace shuts down in a storm, or draws its own exhaust back in.
What a replacement scope should include
- ✓A load calculation on the building as it stands, not the old unit's output
- ✓Vent and combustion air arrangement, including anything else left on the old flue
- ✓Condensate drainage, with neutralisation where it discharges into cast iron or a pit
- ✓Gas line capacity for every appliance the meter feeds
- ✓Return air and filter cabinet sizing, since older systems are short on return
- ✓Plenum and duct connections rebuilt properly rather than adapted with tape
Duct built for a different machine
The furnace itself is the easy part of the day. The duct it connects to was often built for gravity flow or a much older blower, and a variable speed furnace fighting too much resistance runs its blower harder, costs more and sounds worse than what it replaced. We measure static pressure before quoting, so if the duct needs work it appears in the price rather than in a difficult conversation next winter.
What we fit, and what we will talk you out of
We install all major residential brands, including Lennox, Carrier, Trane and Goodman. If the house has no gas service, or the radiators are staying, or the real problem is duct no furnace will overcome, we say so rather than selling you the wrong machine.
Delaware County Furnace Installation — Questions We Get
Do I have to do something about my water heater as well?
If the old furnace shared a chimney with it and the new furnace vents through the wall, then yes. The water heater is left alone in a flue sized for two appliances, and an oversized cold chimney does not draft reliably. The fix is normally a correctly sized liner or a directly vented water heater, and it should be priced with the furnace rather than discovered afterwards.
Is a bigger furnace better in a cold snap?
No. An oversized furnace reaches setpoint fast, shuts off, and repeats, which produces temperature swings, uneven rooms and unnecessary wear. Comfort in cold weather comes from longer, steadier run times, which is what correct sizing and a staged or modulating burner deliver.
Can a high-efficiency furnace vent up my existing chimney?
No. A condensing furnace produces flue gas that is cool and wet, so it is vented in plastic pipe, usually through a sidewall. The masonry chimney is then either relined for whatever else is still using it or taken out of service, and that decision is part of planning the job.
Will my existing ductwork work with a new furnace?
Often it needs help, particularly on the return side. We measure static pressure before quoting so we know what the duct is doing rather than assuming. Where it is restrictive, correcting it usually costs less than the efficiency and comfort you lose by ignoring it for the next fifteen years.
What does the free estimate actually include?
A look at the existing equipment and flue, the panel, the gas supply, the return air and duct arrangement, and the intended vent termination, plus a load calculation on the house. You get a scope naming the equipment and stating what the work covers. Diagnostics on a system that has already failed are separate and are quoted before dispatch.
Which parts of Delaware County does the Drexel Hill office cover?
Drexel Hill, Springfield, Clifton Heights, Lansdowne, East Lansdowne, Yeadon, Millbourne, Collingdale, Sharon Hill, Glenolden, Folcroft, Holmes, Broomall, Darby Township and Tinicum Township among others, with other PJ MAC offices covering the rest of the county.
Who serves Delaware County
Delaware County calls are handled out of our Drexel Hill office at 642 Harper Ave, Drexel Hill, PA 19026. Call (610) 672-3046 — we answer 24 hours a day.