When temperatures drop below zero or even below freezing for extended periods of time, sometimes your furnace can't keep up. If your home is not
Furnaces are built to handle local climates, but very cold weather can push them hard. They work well even when it's 0 degrees Fahrenheit outside. But, using space heaters is risky, as they cause 43 percent of home heating fires each year, says the National Fire Protection Association.
Your furnace can only maintain a differential between outdoor and indoor temperatures to a certain degree. During extremely cold weather, some furnaces might not be able to bring a home up to its desired temperature level.
This may be caused by obstructed airflow or dirty or misaligned gas burners. In some cases, airflow is obstructed by a dirty furnace air filter, and if it is replaced, the problem is solved.
The colder the outdoor temperatures get, the harder your furnace will work to keep up with the thermostat settings in your home. This is why some people choose to lower their thermostat slightly when they notice that the outside temperatures are dropping.
When temperatures drop below zero or even below freezing for extended periods of time, sometimes your furnace can't keep up. If your home is not heating up to the temperature you've set, try lowering it a few degrees. The temperature of the air coming out of your vents doesn't get warmer by turning up your thermostat.
You're not the only one that needs to stay warm during the winter. Unfortunately, when the temperature drops significantly, your HVAC unit is at risk of freezing. A frozen heating system cannot properly warm your home and can lead to permanent system failure.
A dirty filter blocks airflow, which can stop your furnace from heating up all the way. Be certain that you are changing your air filter when needed, as well as check that there are no large objects stacked around the furnace that are impeding airflow. Keep clean ducts and a clear path.
Clogged Air Filters
One of the most common issues with a heating system not functioning is dirty air filters. If your air filters are extremely dirty, then the airflow can be blocked. Check for clean air filters, vents, and registers. Make sure there are no rugs or furniture blocking vents or registers as well.
Radiators might not be getting hot due to trapped air requiring bleeding, a malfunctioning boiler or central heating pump, thermostatic radiator valves that might be stuck or set too low, or the central heating system having sludge or rust which causes blockages.
Your furnace may be producing sufficient heat, but if there is a problem such as a broken blower fan, a clogged air filter, or damaged ductwork, the heated air has no way to get circulated throughout your home.
There are several reasons why your heat pump could be doing this. It could be that your heat pump unit is covered in ice or that it can't endure the freezing outdoor temperature. It could also be that your heat pump is struggling to turn on. Your heat pump not keeping up is an issue you need to resolve ASAP.
The thermostat is the central control of your HVAC system, and malfunctioning can prevent the AC and furnace from turning on. This problem can be due to bad wiring connecting the thermostat to the AC and heater, or a thermostat that has reached the end of its life.
Close your window drapes and blinds. Make sure air vents and radiators are not blocked or obstructed. Keep furnace vents leading outside near ground level clear of snow or ice. If you have a fireplace without glass doors, don't use it during extreme cold weather since most of the heat goes up the chimney.
There may be drafts and pockets of colder air near the floor; The walls are colder and don't emit the usual amount of infrared radiation, so you lose heat due to your body emitting more IR than it receives; You may spend more time indoors and hence have less physical activity, so your body generates less heat.
It is possible the thermostat is set to “cooling mode” which would keep the furnace from turning on to heat your home. If the thermostat is not on heating mode, set it to “heat” and wait to see if your home starts to get warmer. Reset your furnace.
Clean your Air Filters, Vents, and Ducts – A clogged air filter will struggle to meet the thermostat's set temperature since the dirt and debris buildup prevents air from circulating through the vents. And as airflow into living spaces drops, so do comfort levels.
The issue could be as simple as an incorrectly set thermostat, so always double check the settings. A more serious problem is a miscalibrated thermostat (it's sensing the wrong temperatures and shutting the furnace off early) or one that has a bad connection to the control board in the HVAC system.
A bad thermostat can be detected when your AC or furnace is not turning on, your HVAC systems are not turning off, the thermostat not responding, your HVAC system is short-cycling, the room temperature not matching the temperature displayed on the thermostat, and the programmed setting resetting themselves.
First, check to make sure the thermostat is set correctly. You will want to make sure that the fan control is set to auto, and not 'on'. If the thermostat appears set correctly, turn off your heater at the thermostat and check the filter. If the filter is dirty, replace it.
Your house and attic insulation can wear down over time. Your house also may have hidden attics that aren't properly insulated or uninsulated garage walls that are attached to your home, and this can cause problems with heat escape, unwanted airflow, and drafts. Your ductwork has problems.
Faulty thermostat
Thermostat problems are the most common reason a home's heater doesn't provide enough warmth. Homeowners who continually bump up their thermostats and the furnace doesn't heat or engage may be looking at a faulty thermostat.
Increase your home's temperature by a couple degrees above your normal setting now, before the worst hits, and then leave your thermostat alone. Do not turn it back down at night. In this extreme cold, your heating system will struggle to return to where you originally had it set.