Aurora, CO · Freeze Warning

Freeze Warning Tonight in Aurora? The 9-Hour Homeowner Checklist

AuroraHvacPros.com · Updated October 16, 2026 · Aurora, Centennial, Denver & Parker

First freeze of 2026: Friday, October 16
The season's first freeze reached Aurora overnight October 15–16. When the next freeze warning is issued, the night it covers is a nine-hour window — what you do before midnight decides what you pay for in November.

Quick answer Before midnight tonight: shut off and drain the evaporative cooler water line, kill power to the cooler, disconnect and drain exterior hoses, and — most importantly — turn the furnace on and let it run a full cycle to prove it heats. Cooler shutdown is $150, furnace service is $150, and both together are $200.

Freezes on the Front Range do not arrive politely. The first one lands overnight, in a narrow window, and it usually hits before most homeowners have moved on from summer. Here is the practical order of operations for tonight.

Before midnight — the 8 things that matter

1. Shut off the cooler water supply valve

Find the valve feeding the cooler — typically on the line running up to the float valve inside the unit. Turn it off.

2. Drain and bleed the line

This is the step that prevents the expensive damage. Closing the valve leaves the downstream line charged, and the charged portion is what freezes and splits. Open the drain, let it empty, and confirm nothing is left sitting in the line.

3. Kill power to the cooler

Not just the wall switch. Go to the breaker or disconnect. A cooler that comes on during a freeze with no water in the pan can damage the pump.

4. Drain the pan

Standing water in the pan freezes, expands, and corrodes the pan from the inside out all winter. Pull the plug and let it drain completely.

5. Disconnect hoses and drain exterior hose bibbs

An attached hose is a freeze trap. Disconnect it and let the bibb drain. If you have a shutoff inside for the bibb, close it.

6. Blow out the sprinkler system if it is still charged

Sprinkler lines and backflow assemblies are the other classic October claim in this part of the metro.

7. Run the furnace

Set the thermostat to heat and let it run a full cycle to temperature. Do this tonight while it is a convenience, not tomorrow morning while it is an emergency.

8. Check your CO alarms

Test the alarms and confirm the batteries. The first furnace start of the season is when carbon monoxide issues show up, and the alarm is your only warning.

What NOT to do tonight

Do not just throw the cover on the cooler. A cover protects the cabinet and does nothing for the water line. This is the single most common and most expensive mistake.
Do not shut the furnace off to "save it." Idle furnaces do not age better. Run it.
Do not leave the thermostat off overnight. A cold house hides a weak furnace. Let the system prove itself.
Do not wait for the forecast to be certain. By the time a warning is certain, the plumbers are booked.

Timeline: what happens if you skip it

When	What you experience
Freeze night, 12 AM – 9 AM	Water in the line and pan freezes and expands
Friday midday (thaw)	Split supply line leaks into ceiling drywall and insulation
Next few days	Stained or sagging ceiling, wet insulation, repair estimates for plumbing plus drywall plus possibly cooler parts
Spring	Corroded pan, seized pump, weaker cooling — discovered on the first hot day

If you want a technician tonight or tomorrow

Freeze nights are the busiest 12 hours of our fall. Booked visits get scheduled in order and same-day slots go to whoever called first. If you cannot get to the cooler tonight, at minimum kill the power and the water valve, then call first thing.

Cooler shutdown $150 · Furnace service $150

Book both in one visit for $200 — you save $100.

Text, call, or click 303-525-7414 · Repair call $89 flat · 10% off for seniors, military, veterans & first responders

Call 303-525-7414 Text 303-525-7414

Frequently asked questions

How cold does it have to get for a swamp cooler line to freeze?

Water lines in unheated spaces can freeze once temperatures hold near or below freezing for a few hours. A 9-hour window at or below freezing is more than enough.

My cooler already has a cover on it. Am I fine?

Only if the supply line was drained and bled first. The cover is not the protection — the drained line is.

Can I just leave the cooler alone and deal with it in spring?

You can, but you would be betting on a line that is holding water. A split line typically shows up as a ceiling stain rather than a puddle on the roof.

Do you do emergency same-day cooler shutdowns in Aurora?

We take same-day calls in order of arrival during freeze events. Call and we will give you the honest current wait. See our cooler shutdown page for what the $150 visit includes.

General information for Aurora, Colorado homeowners. For official weather advisories, check the National Weather Service. If you smell gas, leave the home and call your gas utility's emergency line.