What has to happen before the first freeze?
Some items are genuinely time-sensitive, because once the ground and pipes freeze the window has closed.
Do these first
- Disconnect garden hoses and drain outdoor spigots — a connected hose traps water in the bib and splits it
- Shut off and drain any irrigation system
- Close crawlspace vents if your home has them
- Insulate exposed pipes in crawlspaces, garages, and unheated basements
- Confirm the furnace actually fires — do not discover a problem on the first 15°F night
What should the furnace service cover?
A real tune-up is more than a filter swap. It should include a heat exchanger inspection for cracks, combustion analysis, safety control testing, flame sensor cleaning, blower inspection, and verification that the venting is clear and intact.
The heat exchanger inspection is the safety-critical item. It is the barrier between combustion gases and the air your family breathes, and a crack is the one furnace fault that warrants shutting the unit down rather than working around it.
Book it in early fall. Everyone in central Iowa calls on the same cold morning, and availability tightens exactly when you need it.
What about the rest of the house?
Winterizing is as much about the envelope as the equipment, and envelope work reduces the load your furnace has to meet all season.
The broader checklist
- Test every carbon monoxide and smoke alarm; replace batteries
- Turn on the whole-home humidifier, replace its pad, and open its water valve
- Reverse ceiling fans to clockwise on low, pushing warm air down from the ceiling
- Seal drafts at door sweeps, window sashes, outlets on exterior walls, and the rim joist
- Clean gutters so meltwater drains rather than forming ice dams
- Test the sump pump with a bucket of water — winter thaws still bring groundwater
- Check attic insulation depth; heat lost upward drives ice dams as well as bills
- Have a backup plan for extreme cold: know where your shutoffs are and keep our number handy
Why does the humidifier matter so much here?
Iowa winter air is extremely dry once heated, and the consequences go beyond comfort. Dry air makes a room feel colder at the same thermostat setting, so people push the setpoint up and pay for it. It also shrinks hardwood floors and trim, causing gaps and separated joints that do not fully close again.
Turning the humidifier on is a two-minute job that most people forget until February. Replace the evaporator pad annually and open the water supply valve — a humidifier with a closed valve or a scaled pad does nothing while appearing to be on.
Frequently asked questions
When should I schedule furnace maintenance in Iowa?
September or October. Scheduling before the heating season means problems get found on a mild day rather than during a cold snap, and appointment availability is far better. Waiting until the first freeze puts you in line behind everyone else who waited.
Do I really need to disconnect garden hoses?
Yes, and it is one of the highest-value five-minute tasks on the list. A connected hose traps water in the spigot and the pipe behind it. When that water freezes and expands, it splits the line — often inside the wall, where you will not find out until spring when you turn the spigot on and water pours into the house.
What temperature should I keep the house at while away in winter?
No lower than 55°F. That keeps pipes in exterior walls above freezing while still saving energy. Turning the heat off entirely to save money on a winter trip is a common and costly mistake in Iowa, and it is not covered by the savings you were chasing.
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