# Maintenance Maintenance determines how well an appliance performs after the first month and how much it costs to run. These guides cover replacement intervals, cleaning steps and power use. _Last updated: 2026-09-28_ ## Articles - [How Much Electricity Does a Dehumidifier Use?](https://www.smartairguide.com/maintenance/how-much-electricity-does-a-dehumidifier-use/) — Estimate a dehumidifier's running cost from watts and duty cycle, see typical daily and monthly figures, and learn how to cut the bill. - [How Often Should You Replace an Air Purifier Filter?](https://www.smartairguide.com/maintenance/how-often-should-you-replace-an-air-purifier-filter/) — Realistic replacement intervals for pre-filters, HEPA and carbon, the signs it is due, and how to estimate annual filter cost. - [How to Clean a Dehumidifier Water Tank](https://www.smartairguide.com/maintenance/how-to-clean-a-dehumidifier-water-tank/) — Clean a dehumidifier tank properly to stop mold and slime: the steps, how often to do it, and the mistakes that shorten the unit's life. - [Portable AC Maintenance Checklist](https://www.smartairguide.com/maintenance/portable-ac-maintenance-checklist/) — A simple in-season and off-season maintenance checklist for a portable air conditioner: filters, drainage, coils, hose and storage. ## What you will find here - How often to replace an air purifier filter - How to clean a dehumidifier water tank - Portable AC maintenance checklist - How much electricity a dehumidifier uses ## Frequently asked questions **Q: Why does maintenance matter so much?** A: A clogged filter or dirty coil reduces performance and raises energy use. Most 'not working' complaints trace back to a filter, a tank or airflow, not a failed part. --- Canonical: