Run the balance test
Close the door, pull the emergency release, and lift the door by hand to about waist height. A balanced door stays roughly where you leave it. If it slams down or shoots up, the springs are out of adjustment and the opener is doing work it should not be doing.
Test the safety reverse
Lay a two-by-four flat on the floor in the door's path and close it. The door should touch the wood and reverse. Then wave something through the photo eye beam while it closes; it should reverse from that too. If either test fails, the opener needs adjusting.
Inspect the cables and springs
Look for fraying where the cable meets the drum, rust anywhere along its length, and any gap in the spring coil. Look, do not touch. Rust on cables is extremely common in New Hampshire because of road salt carried in on vehicles.
Check the bottom seal and the weather strip
A cracked bottom seal lets in cold, water and mice. It is cheap to replace and makes a real difference in an attached garage. Check the side and top stops too.
Clear and level the tracks
Wipe the inside of the tracks with a rag, no grease. Check that they are plumb and that the gap between the track and the door edge is even top to bottom.
Lubricate before the cold arrives
Do this in October, not December. Cold thickens old grease and a door that was fine in fall becomes stiff and hard on the opener once temperatures drop.
Book a tune-up if anything looked wrong
A professional tune-up covers spring tension, cable condition, roller wear, bearing play, track alignment and opener force settings, all of which are the things that actually break.
When to hand it over
If any of this points at springs, cables or a door that has gone out of balance, that is the point to stop. Supreme Garage Doors Repair Services covers same day garage door repair and every other garage door service across New Hampshire, with same-day slots most days and a line answered 24 hours at (888) 904-6236.