Proper furnace cycle and downtime?

I believe this is going to widely vary based on your home construction and insulation. Our farmhouse with open floor plan and not much construction runs longer than our home in town that has much more insulation. Windy days the time between cycles is shorter.

if you know the name or mfg of your furnace you should contact them - or look for a trouble shooting manual for your model of furance online

Kathy Gunter Law is correct. There is no straight answer. The furnace turns on and off based on the thermostat setting and temperature in the room it's located. There usually is a 2 degree differential. Meaning, if you set the thermostat at 70 degrees it basically doesn't turn on until the room temperature drops to 68 degrees and can run till the room temperature hits 72 degrees. Colder days it will run longer to maintain the temperature setting. On cooler days it will run for a shorter time. If you don't have a digital thermostat I suggest you get one. You can get one that just heats and cools or if you need it you can get a programmable one you can program on and off times for every day of the week.

William is correct in noting that the thermostat will activate according to the room temperature where it is located. Where is your thermostat located? Is this area/room usually the same temperature to the rest of the house, colder, or or does it tend to be warmer (for example, if it is nearer to a stove or fireplace) hotter) than the rest of the house.?

It’s your furnace that will set the time change your thermostat sounds like you need another .The thermostat controls when the furnace comes on to control the temp you set it at.so if it’s 60 in the room and you have it set to 70 it will keep coming on till the room is 70

There are a lot of different factors at play that affects furnace cycling: the furnace, the indoor temp, outdoor temp, settings, insulation, and more. You can check your thermostat settings, or find the manual for it if you've saved it or online. It will tell you how to adjust the cycling. Or, if you're at a real loss, call in a trusted pro to help work through your questions. There is no hard-set actual average since every home, furnace, and settings are different.

1 - Low airflow

If your furnace keeps shutting off, it could be due to low airflow. There are several indirect issues that cause low airflow.

• Dirty Air Filters. If you don't change your air filters often enough, the filters will become dirty and clogged, which means the heat exchanger retains heat and eventually causes it to overheat. It's imperative you change your air filters about every 90 days unless you have pets or allergies. If you have pets or allergies, you should be changing air filters every 60 days, or less if your allergies are severe.
• Dirty Blower Wheel. If your furnace goes on and off too quickly, it could be a dirty blower wheel. The blower wheel has blades that push the air and if it has dirt on it, it won't work as efficiently and might ultimately not work at all. You can prevent dirt from building up on your blower wheel by changing your air filters regularly. If you don't, this could end up being expensive to repair.
• Closed or Blocked Air Supply Vents. If your furnace keeps shutting off, check your air vents to see if any of them are closed or blocked in any way. You should keep all your vents open, even in the rooms you don't use. If your heat exchanger doesn't get enough air, it can't transfer enough heat. Then that heat builds up and could end up causing your furnace to short cycle.

2 - Faulty thermostat

Your thermostat is what controls your entire heating system. So, if your furnace keeps turning off and on too quickly, your thermostat might be malfunctioning or broken. There are several things that could be causing your thermostat to not work properly. The wiring could be old and need replacing, it might need new batteries, or it could be the location of your thermostat.

If your thermostat is placed close to a heat source such as direct sunlight or a heat register, it will skew the temperature reading causing the thermostat to turn on and off irregularly. Unless your thermostat just needs batteries, you will need to contact a professional to either replace any old wiring or relocate your thermostat to a more appropriate location.

3 - Flame sensor

If your furnace shuts off too often, you could have a corroded or dirty flame sensor. A flame sensor lets your system know there's a flame when the gas valve is open. If there isn't a flame, the sensor will shut off the gas valve to keep the gas from getting into your house. If the flame sensor is dirty or has become corroded, the flame won't register and will turn off the gas valve, which, in turn, causes your system to shut down. You will need to contact a professional to check this, especially if your furnace is cycling on and off too quickly.

Other possible causes of a short cycling furnace.

If your furnace is short cycling, it could also be any one of the following issues:

Blower motor

The blower motor is what circulates the air throughout your house. It's possible your furnace will run when the blower motor is off; however, that's rare. But on the rare occurrence it does, there wouldn't be any air blowing over the heat exchangers which would cause your furnace to go off. The best way to check this is to hold your hand up near the vents to see if there is any air coming out. If there is no airflow or the airflow is weak, the blower motor is likely the problem.

Flue pipe

The flue pipe, also known as the exhaust vent, is located on your roof and can also cause your furnace to short cycle. This happens when dirt, leaves, sticks, or other debris like a bird or animal nest ends up inside the pipe resulting in a blockage. This blockage will cause hot gases to build up in your furnace causing it to overheat. One of your furnace's safety features includes a mechanism that will trigger your furnace to shut down if it gets overheated.

Over-sized furnace

If your furnace is too big for your home, it could cause it to short cycle. Unfortunately, in this instance, you will have no other choice but to replace your furnace if you want to correct the issue. What happens when your furnace is too big for your home is it will heat your house too quickly then abruptly turn off. Then once your home starts to get cold again the cycle is repeated.

Hello, depending on how insulated your home is, you my have the furnace running more or less if you have good insulation. You may also want to check your thermostat, if it's not working properly it will foul the furnace cycles. Your best bet is to get a pro in to look at this and advise you. Better safe than sorry

You may want to have the gas and electric company come to your house and check your level of insulation and see where you might have areas to improve on. There are options you can do to lessen the exchange of indoor and outdoor air and keep the rooms more regulated and have less fluctuation.

Furnaces respond to the environment they are in, if you suspect a problem with your thermostat, you can try replacing it. You could also have your furnace checked out and cleaned thoroughly, replace your filter as needed. Some companies offer service contracts.