When raise temp. on thermostat 2 degrees, furnace comes on,
temp. rises 1 or 2 degrees. Furnace then shuts off/immediately comes
Back on until temp. goes up 1 degree above set point.
This does not seem normal, and do not remember seeing this before.

Thermostat - White-Rodgers 1F80-51, program off
Gas furnace - Rheem, 10-years, no maintenance done

Freaking werid is this an old thermastat?
Did you say its 10 years old?

About 10 years. I could replace thermostat, but I want to make sure nothing wrong with furnace. It has NEVER been "maintained".
I just change filter regularly.

Call in a service company. If you have neglected this unit for that long then chances are you won't be able to repair it yourself.

I appreciate the advice. Although I can probably change out
The thermostat myself, I do not plan to touch furnace parts.

But, what would one have done to maintain a gas furnace?
I assume (? ) nothing in first few years, but how about
After 10 years? I do vacuum around what I can reach
And change filter.
Am I forced to have a service person do something every year?
I believe that is expensive here in North N.J.

Chances are the tstat is OK,, like the man said earlier after 10 years it needs a good check-up. I doubt it is much more expensive in North NJ than anywhere else,, and it could save you money in the long run

If the burner is what goes off and the motor keeps running and blowing air, I have a suspicion that your fan and limit or just the limit is bad, therefore as the furnace gets too hot the limit turns the fire off but the blower blowing air across the limit cools it to the point to turn the fire back on and then it repeats itself until the thermostat is satisfied.

If this answer helps please let me know and please rate my answer.

If you can remove the face of the thermostat and jump a wire from R to W and it heats as long as the jumper is in place. You got a bad thermostat. If the heat runs for just a few minutes and shuts down with the jumper in place you have problems in your heating system.

But, what would one have done to maintain a gas furnace?
I assume (??) nothing in first few years

And you would be completely wrong. Just because it is new does no mean that you can just neglect it. It is, after all, a machine with moving parts. A yearly cleaning and inspection can catch potential problems before they occur and if a problem does happen during off hours then you will have saved yourself a lot of money. If you think HVAC/R companies are expensive now then wait until 8 PM on the coldest night of the year and see how much more that bill is. Think I'm kidding?



Am I forced to have a service person do something every year?
I believe that is expensive here in North N.J.

Most companies offer a service called a "Clean and Check" and it was it says. It is usually a flat fee. If you have only heat and no A/C then a yearly inspection will be beneficial. If you do have A/C then schedule it twice a year. Once for before heating season and again before cooling season. A piece of advise, DO NOT wait until it starts turning cold/hot. Schedule this well in advance.