Why is the furnace blower motor running but no heat is coming out?
1. The igniter (no more pilot takes the place of the pilot on newer furnaces) is bad and needs to replaced.
2. You have a dirty filter and the high temperature limit tripped the furnace to run the fan constantly without heat to cool the furnace. If the fan doses not shut down and allow the heat to start the limit may need to be reset.
3. The thermostat in the home maybe in the fan/on mode.
How do I change my furnace air filter and were is it located?
The furnace filter can be located in several places. Most common would be to the right or left of furnace there is the sheet-metal return air drop which attaches to side of furnace this may have what looks like a sliding metal door that you can slide it up and filter goes inside. The arrow on filter points to the furnace. If there a bracket to hold filter in place -Good. If no bracket lean filter at a angle so the top is against furnace and bottom is away diagonal from top.
Other Places Filters are Found
1. If furnace is in basement remove bottom panel on furnace and see if its in there.
2. There may be a box *(return air box) that the furnace sits on look for and access panel into box.
3. If furnace is in crawl space and laying down the filter will be typically on the right side of furnace flue connection in the return. Or behind the panel that houses the blower motor which is also to right of flue connection.
4. If the Furnace is the attic the filter or filters can be in the ceiling return air vents or in the attic itself similar to a crawl space furnace.
5. Electronic air cleaner (EAC) - be sure the power is OFF before you begin. EAC filters are washable with 2-3 sections and 4-6 components. First pull off the front cover and remove the big 4 inch wide cells (2 of them) be sure to pull them and reinstall them in the same way & direction you took them out. The pre-filter is a skinny 1/4 inch wire mesh that is first to filter the air there are 2 pieces to this side by side. Slide these out & wash the pre-filters. If the 4 inch wide cells are dirty gentle vacuum the with soft brush. Some EAC's have a hepa filter also vacuum these and re -install all of the above.
How often do I change my furnace filter?
A dirty air filter can cause big problems on a furnace heating exchanger and furnace blower motor. A heat exchanger is like your car engine if you don’t have enough air (antifreeze) removing heat off the surface it runs too hot in the winter. If you have air conditioning a dirty filter can cause the “A” coil that circulates freon located on top of the furnace to freeze in the summer. A dirty air filter can also cause the furnace blower motor to pull more electricity and over heat as well. My advice would be to change the furnace filter at least once every 4 to 6 weeks during heating season and for air conditioning once a month.
What kind of filter do you recommend?
In the winter you can use any kind for heat EZ flow, high efficiency or pleated (accordion type) In the summer for air conditioning I only recommend EZ flow or flat filters. The “A” coil is very easy to frost and needs as much air as the blower motor can push, a high efficiency or pleated filter will obstruct the air flow and cause frosting and eventually freeze in a matter of days to were you have solid block of ice sitting on your furnace.
What Do I do if the coil freezes up?
If in the summertime you notice water on the floor around the furnace and when the air conditioning is on there is no air coming out of the vents you most likely have a frozen coil(coil is attached to furnace or air handler). If you filter is the wrong kind or dirty replace it. Then go to the thermostat and switch cool to off and auto to fan. What this does is run your fan continually without the air conditioning and allows the coil to thaw out (it usually takes 4-6 hrs to thaw).
If that didn't work then you may be low on Freon or your coil is dirty and needs to be cleaned.
Is it a good Idea to run the fan on thermostat all the time to circulate air?
I recommend for homes in summertime to run the fan all the time to circulate the air conditioned air this will keep a more constant temp throughout the house. With homes with vents on the floor it helps to keep the air from stratification (a blanket of hot air on the ceiling and cold air on the floor). Ceiling fans are important too in summer turn them clockwise in winter counter clockwise. You air conditioning will come on and off by the thermostat but the fan will run constant.
Why did my furnace blower motor go out in just a couple years from purchase?
If you have both a heating and air conditioning system and the thermostat is set on auto your blower motor turns on and off every time it calls for heat or cool.
The amount of strain on the motor windings is much higher than if the fan is allowed to just run continually. Ex: If a light bulb is turned on and off continually it will burnout faster than if it was just left on.