Something is wrong with your furnace. Perhaps it’s running louder than usual, making an odd noise or cycling on and off repeatedly — if it’s working at all.

Maybe your whole house is too cold, or some rooms are significantly warmer than others.

These tips will help you determine whether you should replace your furnace or simply repair it, and whether your furnace is actually the reason your home is so cold.  Before you call any company, check your furnace filters first!  The majority of service calls could be solved with changing the furnace filter.  If you don’t know where it is, call; we will tell you.

When you should repair instead

Whether you should repair or replace a dysfunctional furnace depends on which part is causing the problem, how much the repair would cost and how old your furnace is.

Problems with the following parts can almost always be fixed, but if a part is no longer available because your furnace is too old, repair may be impossible:

• Hot surface ignitor

• High/low limit switch

• Anything involving a thermostat

• Gas valve

• Flame sensor

• Thermocouple

• Filters

Signs your furnace is dead

Many experts say you should consider replacing your furnace after 15 years, since it might be reaching the end of its life. We disagree. Some furnaces will last 25 or 30 years — or even longer — so replacing a 15-year-old furnace just because is premature.

An experienced technician might be able to give you an idea of how much life your old furnace has left based on its service history and an analysis of how the components are functioning, but there’s no definitive way to tell.

Problems with the following parts usually means it’s time to replace your furnace:

• Heat exchanger (cracked)

• Blower motor

• Inducer motor

• Control board (sometimes repairable, depending on furnace brand)

If the parts are still under warranty (a typical one runs 10 years) and these items are covered, do the repairs. But these parts often become faulty when the furnace is older. The repairs can be so expensive that replacement makes more sense, especially since one large repair can be the beginning of many repairs.  This is also a good time to get a second opinion. Most heating companies would be happy to sell you a new furnace, rather than repair a 15-year-old furnace.

When your furnace isn’t to blame

If your home is too cold, the furnace isn’t necessarily the culprit. The following fixes are easier and less expensive than furnace repair or replacement. As a bonus, many of these will also make your air conditioner more effective.

Is your furnace getting power? Check for tripped circuit breakers or blown fuses.

Leaky ducts (the metal tubes that distribute heat throughout your home) can be sealed so that more hot air actually gets blown into rooms instead of seeping into the attic. The American Council for an Energy Efficient Economy says sealing leaky ducts can improve efficiency by 15 to 20 percent; it will set you back a few hundred dollars, but that’s much cheaper than a new furnace.

Better insulation in your attic and walls will help your home retain heat. New weather stripping around doors and windows will keep cold out and heat in.

Upgrading a manual thermostat to an electronic one can regulate your home’s heat more effectively and lower your energy bills. And, replacing a furnace’s filter can improve airflow.

A furnace can generate a certain amount of heat per hour. This number is expressed in British thermal units (BTUs). The higher the number, the larger the home the furnace can heat.

Choose the right contractor

Most people will find the cheapest furnace and not care who the contractor is.  You wouldn’t buy a car like this, and your furnace will be with you longer than your car.  When your mother told you “You get what you pay for” she wasn’t kidding.

Who you hire to install your furnace is more important than furnace brand.

Look for contractors who are NATE-certified; the North American Technician Excellence designation means they have passed tests demonstrating real-world HVAC knowledge.

Make sure the contractor is licensed, insured and bonded, and has been in business for many years. You want someone who will be there to service and repair your furnace and honor the labor warranty, which should be for at least one year.

A good contractor will perform a heat load analysis at your home based on square footage, ventilation, windows and insulation before giving you an estimate or recommending a furnace.

The labor estimate should include installation; any adjustments to ducting, venting, fuel delivery or electrical systems; and disposal.

The contractor should provide details about recommended furnace brand, size, efficiency and parts warranty, as well as operating costs.

Proper maintenance saves money

If you don’t maintain your furnace, expect unnecessarily high heating bills from inefficiency and repair bills for preventable equipment failure. You’ll also shorten the furnace’s life.

Most people don’t have the expertise to perform the necessary maintenance functions themselves, but many HVAC contractors offer maintenance plans.

A furnace tune up includes a thorough clean of the system, checking the electrical components and evaluating burners and heat exchangers. This should be done by a licensed service technician who should explain what is being done and offer recommendations for preventative repairs if they find anything operating outside of specifications.”

A thorough inspection will take 45 minutes to an hour.  A maintenance plan that includes two visits per year, ideally one in the spring and one in the fall.

• Contributed by All Star Heating of Fall City.