Filter Lifetime Sensor

The filter_lifetime sensor platform reports how much of a replaceable filter’s life remains, as a percentage, from how long the device has been running and at what speed. Use it for air purifiers, HVAC filters, water filters or any consumable that is replaced after a set number of running hours. The accumulated runtime is stored in flash and survives reboots.

# Example configuration entry
sensor:
  - platform: filter_lifetime
    name: "HEPA Filter Remaining"
    max_lifetime: 180d

Configuration Variables

max_lifetime (Required, Time): How long the filter lasts when the device runs at full speed, for example 180d. At least one minute.
is_on (Optional, lambda): Returns a bool that is true while the device is running. Runtime only accumulates while it is. Defaults to always running.
is_on_sensor (Optional, ID): A binary sensor that is on while the device is running. Cannot be combined with is_on.
current_speed (Optional, lambda): Returns the current speed as a float percentage from 0 to 100. Runtime accumulates in proportion, so an hour at 50% counts as 30 minutes. Values outside that range are clamped and NaN counts as 0. Defaults to 100.
current_speed_sensor (Optional, ID): A sensor that reports the speed percentage. Cannot be combined with current_speed.
runtime_hours (Optional): The accumulated speed-weighted runtime in hours. All options from Sensor.
remaining_days (Optional): The days of full-speed running left before the filter is used up. All options from Sensor.
update_interval (Optional, Time): How often the runtime is sampled and the sensors published. Defaults to 60s.
All other options from Sensor.

The runtime is written to flash once per hour of speed-weighted runtime, on a clean restart or update, and when the filter is reset. A power cut loses whatever accumulated since the last write, up to an hour of counted runtime. A device that is powered together with the appliance and never counts an hour between power cuts never reaches a write, so its runtime falls back to the last stored value at every power cut; give such a device its own power or keep it powered across sessions.

NOTE

The sensor tracks running time only. It does not measure how dirty the filter actually is.

Inputs From Sensors

The running state and speed can come from existing entities instead of lambdas:

sensor:
  - platform: filter_lifetime
    id: hepa_filter
    name: "HEPA Filter Remaining"
    max_lifetime: 180d
    is_on_sensor: purifier_running
    current_speed_sensor: fan_speed_percent
    runtime_hours:
      name: "HEPA Filter Runtime"
    remaining_days:
      name: "HEPA Filter Days Remaining"

Speed From a Select

A fan with named speeds can map them to a percentage in the current_speed lambda:

sensor:
  - platform: filter_lifetime
    name: "Filter Remaining"
    max_lifetime: 90d
    is_on: !lambda 'return id(fan_mode).current_option() != "Off";'
    current_speed: !lambda |-
      auto mode = id(fan_mode).current_option();
      if (mode == "Low")
        return 33.0f;
      if (mode == "Medium")
        return 66.0f;
      return 100.0f;

`filter_lifetime.reset_filter` Action

Sets the accumulated runtime back to zero after the filter has been replaced.

on_...:
  - filter_lifetime.reset_filter:
      id: hepa_filter

id (Required, ID): The ID of the filter_lifetime sensor.

Filter Lifetime Sensor

Configuration Variables

Inputs From Sensors

Speed From a Select

filter_lifetime.reset_filter Action

See Also

`filter_lifetime.reset_filter` Action