Learn about filters

The right filter starts with your equipment.

Understand filter fit, airflow, and care before choosing a replacement. Then set a reminder that fits your home.

Learn about filters

What kind of filter is right for your equipment?

Start with fit and airflow. The best choice depends on your equipment, filter cabinet, and household—not just the number on the package.

Get the size and fit right

Check the equipment instructions and filter cabinet for the correct size and thickness. The old filter can be a useful reference, but it may not be the right one. A filter should fit securely without being forced or leaving gaps.

Match filtration to airflow

MERV describes particle-capture performance. A higher rating is not automatically the best choice for every system. Check your equipment requirements before changing the rating or filter type; Sunset can help assess fit and airflow during maintenance.

Build a routine that fits your home

Follow the filter and equipment instructions, and inspect the filter regularly. Pets, dust, renovation, and heavy system use can change how quickly it loads up. Replace disposable filters; clean reusable filters only as the manufacturer directs.

Before changing a filter: turn the system off at the thermostat and follow the equipment instructions. Install the filter with its airflow arrow pointing in the direction air travels toward the blower. Do not stack filters or add a second filter unless the system is designed for it. Mini-split washable screens follow their own cleaning instructions; they are not interchangeable with central-system disposable filters.

EPA guide to home air filters and filtration →

Make it easier to remember. Choose a filter-check reminder below, then adjust the interval to your equipment and actual filter condition. Reminders do not measure how dirty a filter is.

Filter replacement reminders

Know when it is time to check the filter.

Set a free email reminder or download the dates to your calendar. The filter reminder starts selected below, and you can choose the interval that fits your home and equipment.

A reminder does not book service. See all maintenance reminder options →

Free email reminders—plus calendar downloads.

Choose your dates, confirm the message sent to your inbox, and Sunset will email you when care is due. This free reminder service does not book a visit.

Email service

1. Choose what you want to remember

Select one or more. Unless you choose a repeat interval, non-drain reminders are one-time checks—not an assumed product replacement schedule.

Monthly drain cleaning

A monthly nudge to check and clean your home A/C condensate drain using the method approved for your system.

A/C maintenance

Keep your next professional maintenance visit on the calendar. A known operating problem needs a service call first.

Filter checks & changes

Remember the filter size and the check or replacement interval appropriate for your home and equipment.

Filter size / type (if known)

Last care / replacement dateOptional—leave blank if unknown.

Repeat reminder

First reminder date

Review the date; reminders do not mark work complete.

UV-lamp replacement

Record the lamp model and last replacement. Use its manufacturer’s interval; a lamp that lights up may still be due for service.

Purifier-cell replacement

Keep REME HALO, HALO-LED, Air Scrubber, or other purifier care on your radar without guessing a universal cell lifespan.

Just want the dates?

Download calendar reminders without sharing your name or email. Events are at 9 a.m. in your calendar’s local time, with a requested 15-minute alert. Import the file and confirm your app’s alerts. Shorter months use the last available day.

2. Turn on free email reminders

Save your details, then click the confirmation button sent to your inbox. No paid plan or appointment is created.

Your name

Equipment nickname (optional)Use a nickname, not a gate code or sensitive access information.