Furnace cycling too often? Oversized perhaps?

How often should a gas furnace cycle on and off for those living in colder climates (Canada)? I have noticed that during winter, when maintaining the temperature of the house steady, my furnace tends to turn on every 5-10 minutes, staying on for about 10 minutes each time. I find this to be a little to frequent. I have the specs from the previous owner, and the furnace is 13 years old, 72,000 BTU (82% efficiency) in a 1200 sq foot 2 story home. I am thinking about getting it replaced as it had 3 separate problems this year with components breaking down (hot surface igniter, blower, flame sensor, etc.) and am wondering if perhaps it is oversized (i.e the frequent cycling) and I should get a smaller model?
How long do gas furnaces typically last anyways? I have read on the Internet that gas furnaces can last 20-25 years, but I'm wondering if perhaps that is reflective for warmer climates where furnaces aren't used as much. Over here the furnace is probably on from early October until mid-May.

jonny snipped-for-privacy@hotmail.com wrote:
  Quoted Text Here  
Hi, It all depends how well your house is insulated. I have 2700 sq. ft. 2 storey house with 100,000 btu mid-efficiency furnace. it cycles about every 20 minutes in coldest days in winter. Those are normal wear and tear items you replaced. The blower some times needs oiling for the shaft bearing. I think your furnace has few more years left. I always keep HSI as a spare. Tony Calgary

jonny snipped-for-privacy@hotmail.com wrote:
  Quoted Text Here  
Why do you find that too frequent? Most thermostats have an adjustable anticipator and if that is improperly adjusted it can cause fast cycling as can a poor location of the thermostat.
  Quoted Text Here  
I would say you are iffy age for replacement. I would likely replace it myself in order to take the opportunity for a higher efficiency model. I would not do it because of the cycle issue. I likely would use the opportunity to work out a deal from my tech so it can be replaced at his convenience and that might make it a little cheaper.
I would let the tech do a proper study of your home to determine the correct size for the unit. This can only be done by measuring and computing a number of factors. I know on my home when the time comes (likely sometime in the next ten years) I will have the duct work re-done and maybe add a two zone system.
From the information you provided there is no way anyone can answer your size question unless they are just guessing.
  Quoted Text Here  
Properly sized the local weather does not matter related to the useful life.

If the heat exchanger in there is ok, then its got some life yet.
If you dont like how often it cycles, lots of new thermostats can limit how many times an hour that it'll run. The less times it cycles the more you may feel a temperature rise and drop.
There are SOOOOO many factors that can lose heat in your home. Check for air leaks, crappy windows and insulation.

If the heat exchanger in there is ok, then its got some life yet.
If you dont like how often it cycles, lots of new thermostats can limit how many times an hour that it'll run. The less times it cycles the more you may feel a temperature rise and drop.
There are SOOOOO many factors that can lose heat in your home. Check for air leaks, crappy windows and insulation.

Johny, I live in NS and had the same problem but with an oil furnace. The problem was a programmable thermostat. The stat was too sensitive so I went back to the old mercury round jobbies and the furnace works fine now. I had 3-4 furnace guys in to find out why my furnace was short cycling. Mine was every 4-5 minutes the furnace came on for 2-3 mins and went off...and over and over.
  Quoted Text Here