Why is My Furnace Blowing Cold Air?

Spring is right around the corner. By now, our heating systems have put in a lot of work keeping us warm over the long winter. It's almost time to start thinking about our cooling systems. However, over the next couple months we may find ourselves bouncing back and fourth between needing heat and needing cool air. We can't totally ignore the need for our furnace yet.

If you find that one cool spring day you are needing your furnace, and it begins blowing cold air, there can be many potential causes of that. Here are a list of reasons your furnace may be blowing cold air.

Thermostat Settings
The first and most obvious thing to check is your thermostat. Check to see if it is set to ON or AUTO. If the settings are turned to ON, this means your furnace will continue to blow, whether the heat is on or not. If you change the settings to AUTO, the furnace should only blow when heat is being delivered. There is also a narrow chance that if you just changed to a new thermostat, it may not be compatible with your furnace. Ask an HVAC expert to double check this for you.

Furnace Computer
Newer furnaces with an electronic control panel sometimes need to be reset. Try turning the furnace power switch off and wait for a few minutes. Restart the furnace and see if anything changes. This is similar to having to reboot your computer or wifi router. If the problem continues, call an HVAC expert.

Pilot Light
If you have an older furnace with a continuous pilot light, it may have gone out. A gust of air or a windy day can sometimes cause this. If you don't have the expertise to relight the pilot, call an HVAC expert for help.

Thermocouple
If you have relit the pilot light and it keeps going out, you may have a faulty thermocouple - a sensor that controls the gas valve and ignition. This is a simple fix for an HVAC expert.

Electronic Ignition
Newer furnaces usually come with an electronic ignition with intermittent pilot, or hot surface ignition. The unit may need an adjustment or a replacement. This requires an HVAC expert.

Ducts
If your home's airflow is slightly warm and weak, it could be escaping through holes in your ductwork. Check to make sure your ducts are sealed well and that they are not dirty or clogged.

Flame Sensor
If your furnace starts off warm, then quickly turns cool, the flame sensor may need repair or replacement. A flame sensor that is dirty or worn can cause the burner to keep shutting down. This requires an HVAC expert to repair.

Burner
If the furnace burner is dirty or worn, it can have trouble igniting. Regular maintenance can help prolong the life of the burner. If the burner needs replacement, we recommend having an HVAC expert do this repair.

Whatever the cause of your furnace blowing cool air, regular preventative maintenance goes a long way to avoid costly heating surprises. Most of the problems above can be spotted before they happen if regular maintenance is being performed on your heating system. At 4 Seasons Heating, Cooling & Electrical we are experts, certified to help with all your heating and cooling needs. We are available around the clock for emergency service calls and offer free, no-obligation, in-home consultations where we can recommend the perfect HVAC system for your home's specs and lifestyle. Contact us today by phone at (204) 953-5700 or book online.