It is so frustrating when your heating system goes down. There are a few steps you can take before you have to call a professional. Furnaces can be dangerous, so you must limit what you try yourself.
First of all, change your filter every month. It easy if you buy a good stock of filters and if you have easy access filter grates. Most home improvement stores have replacement grates which you can switch out.
Next, check your duct work. It is very common for ductwork to come apart and you will literally blow your money into a crawlspace or attic. You will also want to look for any blockage in your vents or return grate.
If you system won’t come on, see if there is life in your thermostat. If you have an old style thermostat, change it out with a new digital one. It is a fairly easy replacement. You can pick one up starting at around $30. Make sure you are careful to follow all safety instructions. Is your thermostat set to Auto? Is your temperature set correctly?
Next, see if you have power going to your system. Check the fuses and/or breakers. If they have burned out, there may be a major problem which has caused them to fail. Barring that, have you paid your utility bill?
If you have power, but the system won’t blow out air, then you may have a blower problem. Blowers regularly fail and should be replaced by a professional. The blower is typically like a cylinder with fins on it. You may be able to see in your furnace where the blower is located and you can at least determine if it is jammed or if it has broken off of the motor shaft.
Occasionally the blower wheel and motor shaft become damaged and both have to be replaced.
If the blower wheel is attached and unobstructed, but is hard to turn by hand, then your motor bearings have worn out and the motor must be replaced. If you handle the blower wheel, be very careful because the metal edges can be very sharp.
If you unit has power and it is blinking warning lights on and off, it may simply need to be reset. Flip the breaker off, wait for a few minutes and then flip them back on. This will reset your furnace and, surprisingly will take care of the issue many times.
If your furnace cuts off during the lighting cycle, then there is a problem which needs to be addressed by a professional.
Here are some additional warning signs that your furnace is in trouble. If you encounter these problems, call a Heating and Air Conditioning professional. If you unit is consistently emitting an unusual smell, call someone immediately. You should be familiar with the smell of gas. (Gas actually has no smell, but the gas company adds a smell for safety reasons.) If you smell gas strongly, get out of the house immediately and call the gas company.
If the flames of your furnace are yellow instead of blue, then there is a problem. Yellow flames are not as hot as blue flames, so something is causing an inefficiency.
If your system is making odd sounds, then something is starting to obstruct a moving part within your unit. This will soon lead to failure, so take care of it immediately.
These troubleshooting steps can often save you the expense of a service call and at least will let you know that there is nothing simple that you could have done to avoid a heating repair.