Frequently Asked Questions

Your 10 Most Common HVAC Questions Answered

We understand that for many homeowners, heating and cooling systems are out of sight and out of mind, until something goes wrong. Fortunately, you don’t have to be an expert—just trust an expert, like the pros at Interstate Heating. We’re always available to help and we’ve even created this page with answers to the most common questions you might have about heating, cooling, and indoor air quality systems. Read on or just call us for help—262-246-4772.

1. How can I save money on my monthly heating and cooling bills?

Simple steps are your best bet—change your filters at the recommended intervals so your system doesn’t get bogged down with dust, pet hair, and mold. And commit to annual maintenance because a clean unit will run more efficiently and need fewer emergency repairs.

2. Should I close the registers and doors to areas of the home that I don’t use on a regular basis?

No, because your system was sized to heat and cool your entire home. When you change the area it services, it actually affects airflow in a way that makes your system work harder and less efficiently. A better way to customize temperatures in different rooms is with zoning that’s designed for this purpose, or with a ductless system that can address comfort issues one room at a time.

3. Why is my furnace blowing cold air?

If you have your thermostat fan set to “on,” it will blow air all the time—even when your furnace isn’t heating, which could be why you feel cold air coming from the registers. Also check your filter—if it’s dirty, it can cause the furnace burners to overheat and shut down for safety. Change the filter and check the fan, then call Interstate for experienced furnace repair if you still need help.

4. How do I know if I need to call a service technician for my furnace or air conditioner, or if it’s just my thermostat?

Many of today’s smart control panels will notify you of system failures that require professional help. Check for alerts, and note that if the screen is blank, you may just need new batteries in the thermostat. After that, check to make sure the gas valve and power switches are on, the filter is clean, and the temperature setting is higher (or lower for your AC) than room temperature. Then, if you’re still having trouble, give us a call before things get uncomfortable.

5. Why is there water under my air conditioner or furnace?

The easy answer is that the condensate line may be clogged and you just need to clean the line running to your floor drain. More complicated issues usually involve the evaporator coil, but you’ll need to call a service tech to check this out.

6. Why does my air conditioner have ice on it?

If you have ice on your AC, make sure the air filter isn’t clogged with dirt and that debris has not made its way into the vents, fan, or motor. If a quick cleaning doesn’t resolve the problem, you likely have a low refrigerant charge, due to a leak in the system. You will need to call a professional like Interstate because refrigerants are regulated and require careful handling. Also note that if your unit is 10 or more years old, it may use a refrigerant called R-22, which is being phased out for environmental reasons and in short supply. Depending on the age of your air conditioner, we can help you decide if it’s better to replace or repair it.

7. How do ductless systems work?

As the name implies, a ductless system doesn’t need ductwork—instead it delivers treated air to one or more indoor units through small, flexible conduits connected to a single outdoor air handler. The system uses a heat pump, which can heat or cool air as needed, so it’s a great option to make rooms more comfortable all year long. It’s also very efficient because it doesn’t create hot or cold air—it simple transfers energy in or out of a room to adjust the temperature.

8. What can I do about dry winter air?

Because cool air can’t hold as much humidity as warm air, it’s common for homes to feel dry in winter. This is especially true when air is then heated by a furnace, which wrings even more moisture out of it, causing dry skin, itchy eyes, chapped lips, bloody noses, and other problems. It can even affect hardwood floors, furniture, wallpaper, and more. Adding a whole-home humidifier brings moisture levels back up to the recommended 35 to 50 percent, without the hassle of constantly moving a portable unit or refilling a reservoir.

9. I don’t smoke or have pets—why would I need an air purifier?

Indoor air is often more polluted than outdoor air, usually because contaminants are trapped inside and accumulate over time. Simple things like household cleaners, cooking, air fresheners, or scented candles all contribute to poor air quality, as do fumes from paint and carpeting—and all the dust, pollen, and pollutants you track in every day. An air purifier captures even the tiniest of particles, which can aggravate allergies or cause odors.

10. Does it matter who fixes my HVAC equipment?

Choosing an experienced heating and cooling contractor can actually save you time and money. Instead of looking for a coupon or whoever can fit you in their schedule first, go with a company like Interstate that has installed thousands of systems and stands behind its work. As a Carrier® Factory Authorized Dealer, we have been carefully trained and must adhere to the highest standards of customer service and honest business practices. We can handle even the most difficult job, and we’ll do it right the first time, guaranteed.

If you have additional questions, our team is ready to help. Call us at 262-246-4772 and see why more homeowners and home builders turn to us for answers.

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N53 W24950 S. Corporate Circle
Sussex, WI 53089

Phone: 262-246-4772
Fax: 262-246-0296