A new furnace is only as good as the install. We size it to your home's actual heat load, install it clean, and prove it's running right before we leave.
Here is the part most people never hear at the sales table: a furnace is only as good as the day it goes in. Two identical units, same brand and same efficiency rating, can perform worlds apart depending on who installed them. One gets sized to the home's real heat load, vented correctly, tied into ductwork that can move the air, and commissioned with a manometer and combustion analyzer. The other gets guessed at, wired up, and left running the moment it lights. Same box, very different winter.
An oversized furnace short-cycles, blasts hot then shuts off, wears its ignitor and blower out early, and leaves cold rooms at the far end of the house. An undersized one runs flat-out on the coldest nights and never quite catches up. Skip the venting and combustion checks and you are gambling with carbon monoxide. None of that shows up on the invoice — it shows up in your comfort, your gas bill, and your repair history over the next fifteen years.
Standard Services is a licensed and insured, family-owned and women-owned company based right here in Glen Mills. We install gas and electric furnaces across Delaware and Montgomery Counties, and we treat the sizing math and the commissioning as the actual job — not the afterthought. Every estimate is free, and every install is one we would be comfortable putting in our own basement.
Sizing is where a good install is won or lost, and it is also where the industry cuts the most corners. The old shortcut is to read the BTU rating off the furnace being replaced and order the same again — or worse, to run a rough square-footage rule of thumb and round up "to be safe." Both approaches routinely land homeowners with a furnace that is one or two sizes too big, because the unit you are replacing was very likely oversized when it went in decades ago. We do not carry those mistakes forward.
Instead we run a heat-load calculation on your specific home — the Manual J method manufacturers and code officials recognize as the standard. That means measuring the house rather than guessing: square footage, windows, insulation in the walls and attic, how tight or drafty it is, and the design temperature for our corner of southeastern Pennsylvania. Add it up and you get the number that actually matters — how many BTUs your home loses on a cold January night, which is exactly how many the furnace needs to replace.
An oversized furnace satisfies the thermostat in a few minutes, shuts off, then fires again a few minutes later. That short-cycling wears out the ignitor, blower, and heat exchanger faster, leaves rooms unevenly heated because the air never runs long enough to mix, and can actually feel less comfortable than a right-sized unit that runs longer, quieter cycles. Correct sizing is not a luxury upgrade — it is the difference between fifteen quiet years and a decade of nuisance calls.
When we hand you an estimate, the size on it is a number we can show our work for — and we are happy to walk you through it. It is your home; you should understand why the furnace we are recommending is the one it needs.
Condensing gas furnaces at 90%+ AFUE are the most common upgrade we install across Delco and Montco. They vent through PVC sidewall, sip less fuel, and pair well with a modern thermostat. Single-stage, two-stage, and variable-speed options let us match the furnace to how you actually live in the home.
Where natural gas is not available or a homeowner prefers not to burn fuel indoors, an electric furnace is a clean, simple option with no combustion venting to worry about. We size the heating elements and confirm the electrical service can carry the load before we ever quote the job.
Pairing a gas furnace with a heat pump gives you an efficient electric heat for milder days and the gas furnace's muscle when temperatures drop. We handle the controls and staging so the system switches over automatically, quietly finding the cheapest way to keep you comfortable.
We start with the heat-load calculation, not the old unit's rating. The furnace we set is the one your home's actual BTU loss on a design-cold night calls for — no rounding up "to be safe."
Condensing furnaces get PVC intake and exhaust run to a code-compliant sidewall termination. We confirm slope, length, and clearances — and we check what your old chimney was really doing before we touch it.
New gas line connections are leak-tested, and the electrical whip, disconnect, and low-voltage wiring are landed to code. Tidy, labeled, and inspected — not a nest of wire behind the panel.
A condensing furnace produces water. We route the condensate to a proper drain or pump, trap it correctly, and make sure it can't freeze or back up into the unit through a Delco winter.
We install and configure the thermostat, set staging and fan behavior for the furnace we put in, and make sure the controls actually match the equipment — a step surprisingly often skipped.
Before we leave, we check gas pressure with a manometer, run a combustion analysis, verify the temperature rise across the furnace, and confirm safe, correct operation. The proof, not the promise.
Get a free, no-pressure estimate with the heat-load math done properly. Serving Delaware and Montgomery Counties.
A modern high-efficiency furnace does not vent up the chimney. Because it pulls almost all the heat out of the exhaust, the byproducts leave cool and wet through white PVC pipe run to a sidewall — not the old masonry flue. That is a better, safer way to vent a furnace, but on an install day it can expose a problem hiding in plenty of older Delaware County homes.
In many of those houses, one masonry chimney served two appliances: the furnace and the gas water heater. The furnace's big, hot exhaust is what kept that flue warm enough to draft properly and carry both appliances' fumes safely up and out. Take the furnace off the chimney and switch it to PVC, and the water heater is suddenly left alone on a flue sized for two — an "orphaned" water heater on an oversized chimney. That flue is now too big and too cold for the little water heater to reliably push its exhaust up. It can spill combustion gases, including carbon monoxide, back into the basement.
An orphaned water heater on an oversized flue is a documented code and safety concern. It is exactly the kind of thing that gets discovered mid-install by crews who never looked — turning a one-day job into a scramble.
We look for it before we quote. When your chimney is shared, we plan the fix into the job up front — relining the flue to the water heater's size, or moving it to a proper power-vent setup — so there is no install-day surprise and no unsafe corner cut to keep the schedule. Getting the venting and combustion air right is the quiet part of the craft that separates a furnace that is simply running from one that is installed correctly.
A furnace and its ductwork are one system, and the ducts are the half most installers ignore. You can set the finest variable-speed furnace made, but if the return is undersized or the supply trunk was designed for a smaller, older unit, the new furnace will fight the ductwork every day it runs. That shows up as noisy registers, rooms that never warm up, a blower straining against too much resistance, and efficiency numbers you paid for but never see.
So before we finalize a furnace recommendation, we look at what it will be breathing through — the return-air capacity, the size of the main trunks, and whether the existing runs can deliver the airflow the new furnace needs. Either way, you hear about it before the install, not after.
Undersized returns, leaky joints and disconnected runs in the basement, crushed flex duct, and transitions that choke airflow. We also check that the supply reaches every room it is supposed to — the far bedroom that is always cold usually has a duct reason behind it, not a furnace one.
Most of the time the ductwork is fine and the evaluation simply confirms the new furnace is set up to succeed. When it needs work, we scope it honestly and separately so you can decide with clear information. What we will not do is drop a new furnace onto ducts we know will hobble it and let you find out over the next few winters.
We lay down floor protection from the door to the mechanical room, confirm the plan with you, and shut off the gas and power safely before anything comes apart. Your home is a job site we clean up after, not one we camp in.
We disconnect and haul out the old unit, and this is where we confirm what the existing chimney and venting were actually doing — including whether a shared flue leaves the water heater needing attention.
The new furnace is set level, tied into the ductwork, and connected to gas, electric, and condensate. We run new PVC intake and exhaust venting to a code-compliant sidewall termination and address any flue work planned up front.
We check gas pressure with a manometer, run a combustion analysis, verify the temperature rise, set the blower and staging, and confirm every safety control trips the way it should. This is the step that proves the install.
We clean up, haul away the old equipment, and walk you through the new thermostat, the filter, and what to expect. You get the paperwork for your warranty and permit file before we pull out of the driveway.
"A finished condensing furnace vented through PVC — not the old chimney"
"Commissioning with a combustion analyzer — the step that proves the install"
"Clean, labeled gas, electric, and condensate connections"
Standard Services provides furnace installation throughout Delaware and Montgomery Counties. Whether you're in Swarthmore, Wynnewood, or right here in Glen Mills, we're your local team.
Plus Devon, PA.
Tell us a little about your home and we'll set up a free estimate — with the heat-load sizing done properly, not guessed. Prefer to talk it through? Call us directly.
Free estimates on furnace installation across Delaware and Montgomery Counties — sized, installed, and commissioned to spec.
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