Does A Cold Home Always Mean A Broken Furnace?

Posted on: 20 November 2019


There's not much worse than turning the thermostat up on the first chilly day of the year and finding that your home's vents aren't producing the sweet relief of warm air. It's easy to panic when your heating system doesn't seem to be working, but there are several components that can potentially keep your home from feeling nice and toasty on a cold winter day. If you're wondering whether your furnace might be at fault for the shivers that you're feeling, ask these simple troubleshooting questions to help narrow down the problem.

Is Your Thermostat Set Properly?

This question may seem obvious, but it will be one of the first questions that an HVAC technician asks when you place that service call. If your home uses forced-air heating and a central air conditioning system, then your thermostat should have both a heating and cooling mode. Some thermostats also have dual-usage modes that allow the thermostat to choose between heating and cooling based on the temperature. Confirm that your thermostat is in heating mode and that the desired temperature is set higher than the ambient temperature. If there's still no heat, then move on to the next question.

Is Your Furnace Running?

Thermostats are simple devices. A thermostat in heating mode will turn on the furnace anytime the ambient temperature falls below the temperature that you set. Turn your thermostat up so that it's a few degrees warmer than the temperature in the room, and your furnace should turn on within a few minutes. If it does, then you know that your thermostat is functioning correctly, and you can continue with your troubleshooting. If your furnace remains cold and silent, then it may be your thermostat that is at fault.

Does Your Furnace Have Power?

If your furnace doesn't turn on, then there are two likely causes: a faulty thermostat or a tripped breaker. Even gas furnaces require power since most now use electric ignition, so do not rule out a power problem. Confirm that your furnace has power by checking the breaker for the unit. If the breaker has tripped, then try resetting it and waiting a few minutes. A furnace that is repeatedly tripping repeatedly may have an internal electrical fault that will require professional assistance. Do not use your heating system if it is continuously tripping its breaker.

Is Your Filter Dirty?

A home furnace is designed to operate within a specific temperature range. If your furnace runs too hot, it can cause damage to your heat exchanger. Luckily, modern furnaces are designed with safety measures so that an overheating furnace will shut down. If your furnace runs briefly and then shuts off, check your filter. A dirty filter can reduce airflow across the heat exchanger, causing internal temperatures to soar and ultimately engaging the safety. Replace your filter and check if the problem continues.

What Next?

If you've tried all of the above troubleshooting steps and you're still wrapping yourself up in three blankets just to take a trip to the kitchen, then it's time to call in an HVAC professional. Modern furnaces are robust, so even a more severe problem is likely to be fixable without breaking the bank. The sooner you call in help, the sooner you can get back to enjoying a cozy retreat from the frigid temperatures outside.

For more information on what to do if you have no heat, contact an HVAC technician.