Home Cooling Task Scheduler
Build a seasonal maintenance schedule for the cooling equipment that carries a Phoenix summer, with a printable list and calendar reminders as an .ics file.
What cools your home
Tick what you have. The list adds that equipment’s jobs and hides the other’s, so a household with one of the two never sees the other one’s tasks.
10 tasks, 2 of them critical and 2 of them a certified technician’s job rather than a household one.
Your ticks stay in this browser and are never uploaded. The calendar file is built on your own device; nothing on this page is sent anywhere.
Next on your list
Computing today’s date…
The tasks roll forward from today on the Phoenix clock. The list below shows each one’s next occurrence, and the ticks are kept against the year they belong to.
The cooling season
The normal high first reaches 100 °F on 31 May and last reaches it on 18 September.
The first and last calendar day whose normal high crosses 100 °F. This site counts the window; NOAA publishes the daily normals it is counted from.
NOAA NCEI U.S. Climate Normals 1991–2020, daily, Phoenix Sky Harbor (USW00023183)The freezing nights
The normal low never reaches freezing at Sky Harbor, but January averages 0.4 nights below 32 °F and December 0.1: the two months when an evaporative cooler has to be drained.
December’s normal low is 45.3 °F and January’s 46.0 °F, but individual winters still produce a handful of freezing nights, which is why the cooler is drained rather than trusted.
NOAA NCEI U.S. Climate Normals 1991–2020, monthly, Phoenix Sky Harbor (USW00023183)Air conditioning or a heat pump 4 tasks
Filter, coils, condensate drain, refrigerant
- Book the annual tune-up before the hot stretch, not during it Technician A yearly professional service is the one item on this list that is cheaper done early. It is where the coils are cleaned, the refrigerant charge is checked, the blower is adjusted and the condensate drain is cleared, and every one of those jobs is a call-out waiting to happen once the normal high reaches 100 °F in late May.
- Check the filter monthly and change it at least every three months Critical A clogged filter starves the system of air and pushes the dust it trapped straight onto the coil. ENERGY STAR’s floor is a check every month through the season, a change whenever the filter looks dirty, and a change at least every three months: the monthly visit is the point, because this valley loads a filter faster than a calendar expects.
- Flush the condensate drain and check the pan A cooling system pulls a great deal of water out of the air, and it leaves through one small line. When that line silts up, the water backs up into the pan and then into the ceiling. Flushing it is a two-minute job at the start of the season and again at its height, and clearing it is part of the annual tune-up.
- Refrigerant is a certified technician’s job, not a top-up Technician If a system is not cooling, the refrigerant charge is a symptom rather than the fault: refrigerant does not get used up, so a low charge means a leak. EPA rules prohibit knowingly venting refrigerant, and handling it requires Section 608 certification, so the household’s job is to notice the symptom and call someone certified, not to add anything.
An evaporative (swamp) cooler 6 tasks
Pads, pump, belt, water tray, winterising
- Spring start-up: fit new pads, set the belt, fill the tray The cooler’s season begins with the work the manufacturer and the extension guidance both put in spring: replace the pads, press the fan belt to check it gives about half an inch, oil the blower bearing and the motor if there is a receptacle, and bring the water to about an inch below the top of the tray. Start the water pump a few minutes before the fan so the pads are wet, and crack a window in the rooms being cooled.
- Wait for 85 °F, not 79 °F, before running the cooler The extension guidance is specific about the thermostat: hold off starting the cooler until it is warmer outside, because running it at a lower set point uses a great deal of water to no purpose. The same guidance says to run only the fan on cool evenings, and never the pump.
- Replace the pads, and expect to change or reverse them again mid-season Aspen pads are what the guidance names. They load with the valley’s mineral dust and stop passing air evenly: the pump may be running while half the pad is dry. A second look at the height of the season is normal here, not a sign that something is wrong.
- Check the water level, float valve, trough and pump Monthly through the season: confirm the water sits about an inch below the top of the tray and below the overflow pipe, adjust the float arm if it has drifted, make sure the pads are wet evenly across the face, and clear the distribution trough. A sticking float wastes water continuously, and a scaled pump stops lifting it at all.
- Descale the mineral build-up Hard water leaves scale on the pads, the trough and the pump impeller; vinegar dissolves it, and the extension guidance gives that as the household remedy. Scale at the end of a Phoenix summer can be the difference between a cooler that cools and one that only moves warm air.
- Winterise the cooler before the first freezing nights Critical Drain and scrape the tray, clear the water trough, dry the pan and seal it against rust, disconnect the water line and blow it out so it cannot freeze, and cover the cooler. January and December are the only months whose nights reach freezing here, and an undrained line is the part that splits.
Both kinds of equipment are unticked, so the list is hidden. Tick what cools your home to bring the tasks back.
Why the list is built from the equipment rather than from a template
A refrigerated system and an evaporative cooler are two different machines with two different calendars, and almost every home-maintenance list on the web flattens them into one. That flattening is where the trouble starts: a household that runs a swamp cooler reads a filter schedule that does not apply to it, and a household with an air conditioner reads instruction about pads and water trays that it has no use for. This tool asks one question first (what cools your home) and builds the list from the answer.
For a refrigerated system the work is a filter that loads with the dust this valley moves, a coil that trades heat with the outside air across a long hot season, a condensate line that carries away the water the system pulls out of the air, and refrigerant that only a certified technician may touch. For an evaporative cooler it is pads, a pump, a belt and a water tray, and a season that hinges on the dew point rather than the calendar. The two lists share the same shape (a task, the month it falls in, and the source that says so) and nothing else.
The season, and why the dates roll forward
The cooling year here has a beginning and an end that can be traced. The normal high first reaches 100 °F on 31 May and last reaches it on 18 September, counted by this site from the National Weather Service’s daily normals for Phoenix Sky Harbor. The freezing nights are the mirror of that: the monthly normals put roughly half a night below 32 °F in an average January and a tenth of one in December, and every other month at none at all. Those two facts set the shape of the panel: the spring start-up and the autumn winterising sit at the edges of the hot window, and the winterising has to be done before the freezing nights, not after the first one.
A calendar written for a fixed year is wrong by the following spring, so this one is not written for a fixed year. Every task carries the months it falls in, and the panel works out its next occurrence from today’s date on the Phoenix clock: Arizona is on MST all year, so there is no daylight-saving shift to get wrong. The tick you leave against a job belongs to the year of that occurrence, which means the filter you changed late last summer comes back on the list next spring rather than staying struck through forever.
What is a household job and what is not
The items marked “Technician” are marked that way deliberately. Refrigerant is the clear case: federal rules require Section 608 certification to handle it, prohibit knowingly venting it, and rest the whole thing on a fact most “top-up” advice ignores: a working sealed system does not consume refrigerant, so a low charge means a leak. The household’s job is to notice that the system is not cooling, and to call someone certified. The annual tune-up is a technician’s job for a gentler reason: the coil cleaning, the charge check and the blower adjustment are each a call-out waiting to happen once the normal high passes 100 °F in late May, so the cheap month to book it is March.
Everything else is a household job on purpose. The filter is the single most important item on the list and costs almost nothing: the federal guidance is a check every month through the season, a change when it looks dirty, and a change at least every three months, and in this climate the monthly check is the point. The condensate line is a two-minute flush at the start of the season and again at its height, and the alternative (a line that silts up and overflows into the ceiling) is the most expensive small thing on the page.
The evaporative cooler, which is its own kind of equipment
An evaporative cooler cools by pulling air through wet pads, so its maintenance is the maintenance of a small water system. The Arizona extension guidance is the authority used here: replace the pads in spring and look again at the height of the season, press the fan belt to check it gives about half an inch, keep the water about an inch below the top of the tray, run the pump a few minutes before the fan so the pads are wet, and hold off starting the cooler at all until it is genuinely warm: the guidance puts that point at 85 °F. Hard water leaves scale on the pads and the pump impeller, and vinegar is the household remedy the extension names. The season ends with the winterising: drain and dry the tray, blow out the water line so it cannot freeze, and cover the cooler, all before the freezing nights the record puts in December and January.
Where this list stops
It is a calendar, not an assessment. It does not know your equipment beyond the two broad kinds, it cannot tell you whether your coil is fouled or your charge is low, and it does not estimate what any of it costs. The manufacturer’s schedule for your model outranks this page on every item. What the tool does is put the right jobs in front of you in the right months, each with the source that says why, filtered to what you actually have, printable for the garage wall and exportable to the calendar you already carry, which is the form a maintenance schedule has to take if it is going to be followed rather than admired.
- ENERGY STAR (U.S. Environmental Protection Agency): “Heat & Cool Efficiently”
The filter routine in the federal programme’s own terms (a check every month through the season, a change when it looks dirty, and a change at least every three months), which is the task the whole list is built around.
- U.S. Environmental Protection Agency: Stationary Refrigeration and Air Conditioning (Section 608)
The refrigerant rule: that handling refrigerant requires Section 608 certification and that knowingly venting it is prohibited, which is why the refrigerant item is written as a technician’s job rather than a top-up.
- University of Arizona Cooperative Extension, WaterWise: “Swamp Cooler Maintenance”
Every evaporative-cooler task: the spring start-up, the pads, the belt tension, the water level about an inch below the tray top, the 85 °F running point, the descaling with vinegar, and the winterising that drains the line before the freezing nights.
- NOAA NCEI U.S. Climate Normals 1991–2020, daily, Phoenix Sky Harbor (USW00023183)
The 100 °F window that decides when the cooling season opens and closes: the first and last calendar day whose normal high reaches 100 °F.
- NOAA NCEI U.S. Climate Normals 1991–2020, monthly, Phoenix Sky Harbor (USW00023183)
The freezing-night counts for January and December, and the normal lows for those months, which are the reason the evaporative cooler is drained rather than trusted through the winter.
Every figure this tool uses was read from the source named above on 11 October 2026. Anything still waiting on a check is listed in the site's data notes rather than shown here as if it were settled.
Before you rely on this
This tool works from climate normals and published guidance, not from live weather. It describes a typical day for the month or date you chose, which is useful for planning and useless as a forecast.
- The dates are the month a job falls due in, not an appointment. Most of these are seasons rather than days: a filter checked monthly through a seven-month summer is a habit, and pinning it to one date would produce a calendar that gets ignored by July. The three jobs with a real deadline in the sequence are the spring start-up, the winterising, and the pre-season service.
- The list knows nothing about your equipment beyond the two broad kinds. A packaged unit, a mini-split, a heat pump, a two-stage system and a window unit all have different service intervals, and the manufacturer’s schedule for your model outranks anything here.
- Nothing here is a repair instruction. The items marked as a technician’s job are marked that way because they need certification, tools or both, and a household doing them is at best wasting money and at worst breaking the law or the machine.
- The climate figures are the 1991–2020 normals for Phoenix Sky Harbor, so they describe a typical year at one urban station. A yard in Queen Creek runs hotter and a yard in Wickenburg runs cooler, and the season windows shift with them. The thresholds (100 °F, 32 °F, 85 °F) are the numbers the equipment and the guidance actually turn on, and they are stated rather than buried.
- The evaporative-cooler guidance is written for the pads the extension material names. A cooler converted to a different pad type, or one run on a thermostat tied into a whole-house system, will not match every line. The extension page is the authority; this tool is a calendar of it.
- The tool stores only which items you have ticked, in this browser, under one key shared with the pool planner. Nothing is transmitted, there is no account, and clearing your browser data clears the ticks. The two tools keep their ticks apart by prefixing every item, so one does not overwrite the other.
- The cost of any of this is not estimated. The site does not predict a bill, does not know your rate plan, and does not claim that a maintenance task will save a particular number of dollars. The utility’s own plan pages and the on-peak habits tool are where the money question lives.
- A task ticked in one year does not read as done in the next. The year is part of the item, so the filter you changed in September comes back on the list the following spring rather than staying struck through forever.