Is Your Gas Furnace Blowing Out Cold Air?


Every so often, life throws us a small, unpleasant curve.

You bite into a shiny red apple, and find out it’s bland and pulpy inside. You congratulate yourself for leaving early for work, only to run into construction.

Or you fire up your gas furnace, but only feel cold air blowing out.

We can’t help you with your produce or your commute to work, but we can help you diagnose what’s going on with your furnace.

In some cases, it might just take time. Just as the water in your sink or shower takes time to get as warm as you want, so does your furnace.

Beyond that, there are a few common reasons why it might be blowing cold air.

1. Check your thermostat

Checking your thermostat. This is the first thing you need to check if your furnace is blowing cold air.This is one of the first things a service technician would check. If your thermostat’s fan setting is switched to “On,” the furnace blower will run non-stop, even if your furnace isn’t heating the air. The fix here is simple: change the fan setting to “Auto,” so that your furnace only emits warm air.

2. Check your pilot light

Gas furnace pilot light. Make sure that it is on if you are experienceing cold air in your home.If you have a gas furnace that’s only sending out cold air, check your pilot light. If it’s out, try relighting. If the flame stays lit, your job is done.

If the pilot won’t light, make sure gas is moving into the furnace. If the gas valve is on, check to see if the pilot light is dirty. Cleaning it will allow gas to come through.

Finally, you might have a pilot light that comes on but won’t stay lit. This suggests an issue with the thermocouple, which will need to be replaced or adjusted. This is a job that might be best left to a heating and cooling professional.

3. Overheating

When your gas furnace blows hot air, then goes cold, and then stops blowing any air at all, that may be a sign that your unit is overheated.

When a furnace overheats, the most common cause is a dirty air filter, which blocks the flow of air and causes the furnace to work harder. This is another simple fix: Just put in a clean filter, and see if your furnace starts to send out only warm air.

This isn’t something you should let go unchecked. If your furnace overheats too many times, you might be left with a damaged heat exchanger, which can be costly to repair.

4. Investigate your ductwork

If your gas furnace is blowing cold air, and none of the solutions we’ve mentioned so far have helped, check your ductwork.

Maintenance ductwork for your furnace to assure a steady flow of warm air.There may be a leak in your ducts, which is causing warm air to escape into your attic, leaving you with cold air. You may also have enough dirt or debris collecting in your ducts to slow the flow of air.

There are some furnace repair issues you shouldn’t try to tackle on your own. If that’s the situation you’re facing, All Seasons Comfort Control can help.

Contact us today, and our expert technicians will get started on diagnosing whatever it is that’s ailing your heating system.