Five Furnace Checks to Make Before the First Freeze in Northwest Indiana

Every fall the same furnace checklist goes around: change the filter, test the thermostat, clear the area around the unit. All true, and none of it explains the no-heat calls we actually get in January. Those calls come from problems specific to where you live. A furnace in Chesterton fails differently than one in Kouts, and a furnace a mile from the lake fails differently than one in the middle of Valparaiso.

Here are the five checks we would add to any list for a home in Porter County or the neighboring parts of Lake and LaPorte Counties. None of them take more than a few minutes, and two of them you can do without going into the basement.

1. Find the two white pipes on the outside of your house

If your furnace was installed in the last fifteen years, there is a good chance it is a high-efficiency model that breathes through two PVC pipes coming out of a side wall rather than up the chimney. One brings in air, the other sends out exhaust. The furnace will not run without both of them clear, and it will shut itself down rather than try.

Go find them now, before the snow. Note which side of the house they are on. If they face the direction the wind comes from, or they sit low enough that a normal snowfall reaches them, you already know what will happen after the first real lake-effect storm. The morning after, if the furnace is off and the thermostat is calling for heat, those pipes are the first thing to check. Clear the snow and ice and the furnace will usually restart on its own.

This is the single most common reason we get a no-heat call in Chesterton, Porter, and Burns Harbor after a storm, and in most cases the homeowner could have fixed it in thirty seconds.

2. If your furnace uses the chimney, think about the wind

Older furnaces, the 80 percent models that vent through a masonry chimney, have a different weakness. They depend on natural draft to pull exhaust up and out. On a calm day that works fine. On a day when the wind is coming hard off the lake, the draft can stall or reverse, and the furnace will light, run for a minute, and shut down. After a few tries it locks out.

Homeowners usually assume the furnace is dying. Often it is not. The venting needs attention, not the furnace. If you have a chimney-vented furnace and it only acts up on windy days, that pattern is the diagnosis, and it is worth mentioning when you call. Homes in Porter and along the lakeshore see this more than anywhere else we work.

3. Check the room the furnace lives in, not just the furnace

A lot of furnaces in older subdivisions, especially around Lakes of the Four Seasons and parts of Portage, sit in a utility room that was framed in years after the house was built. The furnace needs air to burn fuel. If the room was closed off, the door was weatherstripped, or a louvered door was swapped for a solid one, the furnace is slowly being starved.

The symptoms are a furnace that short-cycles, trips its safety limit, or runs but never seems to catch up. People replace the limit switch and the problem comes back a week later, because the switch was doing its job. If your furnace is in a closed room, make sure there is a path for air to get in. A louvered door or a vent in the wall is usually all it takes.

4. If you are on propane, check the tank and the regulator

Outside the natural gas lines around Kouts, Hebron, Wheeler, and the rural parts of the county, most homes heat with propane. Two things to check before winter. First, the tank level, because a furnace that runs out of fuel during a cold snap is a no-heat call with a simple cause and a long wait for a delivery. Second, the regulator at the tank, which can ice up in freezing rain and starve the furnace of pressure. If the regulator has no cover or hood, that is worth fixing in the fall.

One more propane note. If your furnace was replaced at some point and was not properly converted from natural gas to LP, it will run, but it will run badly and wear out early. If you are not sure, it is worth a look.

5. Note how long it takes to warm up on the first cold morning

This is the check that catches a furnace before it fails. On the first morning the house drops into the 60s, set the thermostat up a few degrees and pay attention to how long the furnace takes to get there. A healthy furnace in a reasonably insulated home should move the temperature steadily. If it runs for an hour and gains a degree or two, something is restricting it: a filter, a weak blower, a duct problem, or in older units a heat exchanger that is starting to go.

That last one matters. A cracked heat exchanger is a carbon monoxide risk, and it does not announce itself. On any furnace past its mid-teens, a professional inspection before winter should include a look at the exchanger. If yours has not had one in a few years, schedule it.

When to call, and what to expect

If you find a problem on this list, or your furnace is doing something not on it, Apex repairs every brand of furnace in Porter County and the surrounding area, with emergency calls answered around the clock. Every visit starts with a diagnosis and a clear price before any work begins. If the repair is the first of several on an aging unit, we say so and give you the numbers for both repair and replacement.

Furnace repair pages for the towns we serve most: Valparaiso, Portage, Chesterton, Hobart, Porter, Burns Harbor, Lakes of the Four Seasons, and Merrillville. If the furnace is past saving, our furnace installation and replacement page explains how we size and quote a new one.

Call (219) 299-7134 or use the contact form on any page to schedule a pre-winter inspection.