A: If I understand your letter correctly, you have replaced the fan door on the furnace with a filter to increase the amount of return air available. This is very dangerous. By allowing the fan to ...

Remove the Combustion Chamber Door DIY furnace maintenance will save you from needing a new furnace. To fix your furnace, first flip the electrical power furnace switch to “Off.” ...

Turn off the furnace by flipping the furnace switch. It should be on or next to the furnace, and looks like a standard light switch. Find the filter service rack or door. This is most likely on ...

If people come to your door to check your furnace, don’t let them in. They may induce you to replace it for a rental unit that costs more money.