- Category: Common GAS FURNACE Heating Issues
- Published: 26 January 2015
Q. How long should my gas furnace last?
A. A gas furnace will typically last 20-25 years.
Q. Can my gas furnace work if the power goes out?
A. No. Even though your furnace uses gas to heat, all of the other components (motors, control boards, etc.) require power.
Q. How often should I replace my air filter?
A. That depends on two factors 1) the type of air filter in your furnace and 2) the amount of dust in the air. In a clean environment, a standard 1" filter should be replaced every 2 to 3 months. A media air filter (4 to 5" thick) has a much larger surface area and generally only requires replacement 2 times per year. In a heavy-dust area the frequency may increase dramatically.
Q. What type of filter should I use?
A. If you have a 1" disposable filter, we recommend using a standard-efficiency, pleated filter (high-efficiency, ultra-allergen filters tend to cause too much airflow restriction). If you have a media air filter, you should stick with the exact style and brand. A different brand (even though the same dimensions) may not fit the cabinet correctly and allow unfilterd air through your system.
Q. Where can I purchase replacement filters?
A. Common sizes of 1" replacement filters (16x20, 16x25, 20x20, 20x25, 25x25) can be purchased at most hardware or home improvement stores. Odd size and Media air filters have to be purchased at a HVAC supply house, a heat contractor or ordered online. GHAC stocks and sells all types and sizes of air filters.
Q. Is it okay to leave my filter out for a little while?
A. Your furnace does not need the filter to operate. The filter is just there to catch dust particles in the air as it circulates through your home. If a system goes unfiltered for an extended period of time, internal components can become clogged and reduce system capacity. Leaving the filter out for a day or two, however, generally won't cause any measurable trouble.
Q. Should I buy a new programmable thermostat?
A. A programmable thermostat is a good idea if you have a normal schedule when you are away from your home. Honeywell says that you can save 15 - 20% on your home heating and cooling costs by setting your thermostat temperature up or down while you are away. But, if you are normally home during the days then a programmable thermostat will likely be more trouble than it is worth.
Q. Should I set the "Fan" switch to "On" or "Auto"?
A. The furnace will operate fine in either position. In the "Auto" position, the fan will come on only when your equipment is operating for heating or cooling. In the "On" position the fan will run continuous and the heating and cooling will cycle on and off as needed. Some people like to leave the fan in the "On" position to provide more air circulation, more air filtration and more consistent temperatures throughout the home.
Q. What should I do if I smell gas?
A. Any gas leak is potentially dangerous, so be vary cautious. 1) If you smell gas in your home, away from any gas appliances, you should call the gas company. If the smell is very strong, you may consider leaving the house and even turning the gas off at the gas meter. 2) If you only get a slight smell of gas when you are near your furnace or water heater, you should call a plumber or HVAC technician to check the equipment.
Q. Should I purchase a carbon monoxide detector for my home?
A. Any home that has any type of gas appliance could benefit from a carbon monoxide detector. New gas furnaces have very little chance of producing carbon monoxide, but a CO detector is still a wise choice.
Q. Should I be concerned about holes rusted in my vent pipe?
A. Yes. Not to say that all rusted piping needs replaced, but if you notice holes rusted through your furnace or water heater venting system, you should have it checked by a qualified technician.
Q. Can a furnace use PVC pipe for venting?
A. New, high-efficiency (over 90%) gas furnaces require PVC vent piping because of the lower vent temperatures and the resulting condensation. Furnaces lower than 90% efficiency must be vented with metal piping.
Q. Should my furnace be making water when it runs?
A. 90% efficient, and higher, gas furnace have much lower vent temperatures which will cause condensation during heating cycles. The furnace will have a drainage system to remove the water that drains from the venting system.
Q. Is there any maintenance I should be doing to my furnace?
A. The primary maintenance function that homeowners need to perform is keeping a clean air filter in the system. Other tasks may include cleaning the drain line.
Q. How often should I have my furnace be serviced?
A. The manufacturer would prefer that you have your unit serviced each season. GHAC offers a very cost-effective maintenance program that provides seasonal equipment maintenance.
Q. What should I do if my pilot goes out?
A. Most old gas furnaces (more that 25 years) have a "standing pilot". The pilot light must be lit before the main burners can operate. If the pilot goes out, you may try re-lighting it one time. If the pilot will not stay lit or goes back out after a short time, you should have it checked by a qualified technician. * Newer gas furnaces have an automatic ignition system. Do not try to manually light a furnace that does not have a standing pilot.
Q. Why does my furnace smell bad when it comes on?
A. It is normal to get a burning odor (like burnt toast) from your furnace the first time you turn it on in the fall or after it has been off for an extended period of time. This odor is caused by dust that has accumulated on the heat exchanger. The odor should go away after one or two cycles.