The decision to repair or replace is up to you, and often it’s a matter of comparing the cost to repair, taking into account the age of the equipment, versus the cost of a new furnace that likely offers higher energy efficiency and comes with warranty coverage. There is no easy answer, but many use the rule of thumb that if a repair adds up to around 50% of the cost of a new furnace, replacing is probably a better solution. If the current system has not incurred other major repairs, is in otherwise excellent condition, and issues that led to the breakdown can be identified and remedied, repairing the unit can make a lot of sense as well.