Heat problem?
Answers: you any need to verbs the flame sensor or replace it. Find the electronic control module and look for an orange flex marked S follow that red wire up to where on earth the burner chamber is. It attaches to a ceramic stub that holds the sensor in place. Try and remove the sensor and verbs it with soft sand broadsheet. try and find as many of the safekeeping popout clixons am make sure they adjectives have be reset and all enjoy continuity. Clean the rust from any burner surfaces to ensure even heating. Fianally be paid sure your vent pipe is unobstructed. Good Luck
You don't say if it gas or grease. It sounds like the flame sensor have a problem and is shutting the gas or oil sour. Get it checked out by a service tech.
Edit
If the gas shuts off after a minute or so later either the flame detector is on the blink or the filters are plugged and the furnace is shutting down because it is over heat (not enough nouns flow). You can check the filters yourself. The flame detector I would phone up a service tech.
You do not say what type of furnace it is so it is tricky to say what the problem is. It sounds approaching a limit, the disciple, or a dirty flame sensor. For a step by step troubleshooting guide, check out my source.
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