What a furnace tune up actually includes
The word covers everything from a filter swap to a full combustion analysis, so it is worth knowing which one you are being sold.
4 min readUpdated
Tune up is not a defined term. Two companies can both use it honestly and do very different amounts of work, which is why the same service is quoted at wildly different prices. Ask what is on the checklist before you compare anything.
The parts that matter
- A combustion check on the burner, with readings rather than a look. This is the safety item.
- Inspection of the heat exchanger for cracking or corrosion.
- Cleaning the flame sensor and checking ignition on a cold start.
- Static pressure across the system, which is the number that tells you whether the ductwork is fighting the blower.
- Blower wheel condition, because a dirty wheel quietly costs airflow every year.
- Condensate drain and trap on a high efficiency unit.
- Thermostat calibration and a full cycle test from a cold start.
What a tune up will not do
It will not make an undersized system heat a room it was never sized for, and it will not extend the life of a heat exchanger that has already cracked. A good visit ends with a plain statement of what was measured and what it means, including the answer nobody enjoys giving, which is that a repair no longer makes financial sense.
When to book it
Before the first hard freeze, not during it. Heating faults surface on the first cold night of the season, which is the same night every furnace in the county gets its first real run and the same night every schedule fills. Autumn is not a marketing preference; it is the only time the work can be unhurried.