Furnace Blowing Cold Air, Do I Need An HVAC Repair Technician? – How To Troubleshoot The Problem.
Are you turning on your furnace, but it is blowing cold air? Are you wondering what is wrong? Well, the truth is that it could be multiple issues, of which some of them you can solve. Before you go right ahead to call a professional HVAC repair Technician, below are 4 troubleshooting techniques that will help.
1. The Thermostat’s FAN Setting
Is your furnace blowing cold air sometimes and hot the other? Well, the problem could be the thermostat’s fan setting, which may be at the ON position. It is important to note that the blower is controlled by the Fan setting control. It is the system that helps circulate air through your home. As such, if it has been set to ON, the blower will run all the time (24/7), regardless of whether the furnace is heating or not. This may be the reason you are getting cold air.
The solution? The only solution to this problem is to ensure the fan setting has been set to AUTO and not ON. The AUTO setting will ensure the fan will run only when the furnace heats the air.
2. The Furnace’s Air Filter
If your furnace is blowing cold air, the problem could be its air filter (meaning it is too dirty). When the air filter becomes too dirty, it limits the flow of air to the furnace’s heat exchanger, which makes it overheat. When this happens, a high limit switch will be tripped, which shuts off the furnace banners to prevent cracking.
The Solution? The solution is to first turn off the furnace at the thermostat and inspect the filter. If it is too dirty, changing it is the only way. You may also need the services of a professional HVAC repair technician to help you reset the furnace. Filters are generally located next to the blower in many models.
3. Inspect The Pilot Light
If you have an older furnace model with a standing pilot light, then you should inspect it. if the pilot light is not lit, then it means that the furnace’s burners will light, which means no heat.
The Solution? You should try relighting the pilot light. Below are steps to follow.
- Switch Off The Furnace – This includes switching the thermostat from HEAT to OFF.
- Locate The Furnace’s Pilot Light Assembly and Reset Switch – The switch and assembly are generally located near the bottom of the furnace. If you cannot locate them, then refer to your furnace’s manual. You must open the cover to access the reset switch. You should see a knob with 3 settings; ‘ON’, ’OFF’, and ’Pilot’.
- Turn The Knob ‘OFF’ and Wait for at least 3 minutes – Doing this will shut the gas flowing through the pilot.
- Turn The Knob To ‘Pilot’ and Press the Knob Down – By doing this action, you will be restarting the flow of gas to the pilot.
- While Still Pressing The Knob, Hold a lighter to the pilot opening Until The Flame Lights – The flame should have a steady blue cone and hit the middle of the thermocouple (this is a small copper bar)
- Turn The Knob To The ‘ON’ Position – Now the furnace should ignite.
- Turn ‘On’ The Furnace At The Thermostat
- Turn the thermostat back to ‘HEAT’, and ensure the temperature is set 5 degrees below the room temperature. After doing this, you should be getting hot air.
What To Do If The Pilot Light Does Not Light Or Stay Lit
Well, this is the point you call a professional HVAC repair technician. The problem may be a malfunctioning thermocouple or other issues that make the pilot light not to burn properly.
4. Inspect The Condensate Line
If you have a high-efficiency furnace and you see water pooling around the furnace, then most likely the condensate line is blocked. The line is usually a PVC pipe. This problem will make the furnace to shut down.
How? You may ask.
High-efficiency furnaces create water when running, which is then drained to the common house’s draining line. However, if the condensate is blocked, water begins to back up into the furnace. At this point, the overflow will trip a kill switch, which will turn off the furnace to prevent water damage.
Common causes for blockages include:
- Broken condensate pump (in this case, you will need the services of a professional HVAC repair technician)
The Solution? Apart from broken condensate pump, the rest can be solved by simply unclogging the line. You can achieve this by following this tutorial on Energy Vanguard.
AC Man is a professional HVAC repair company in Houston, TX. We offer both commercial and residential HVAC services. Give us a call today to speak with a professional HVAC repair technician, or check our services.