User Manual for Acurite 00891A2 Thermometer
Quick guide for the Acurite 00891A2 thermometer. Learn how to install batteries, place the wired sensor, use the MAX/MIN memory function, and understand display readings.
Table of contents
Manual images
Click an image to enlargeQuick guide from the manual
This thermometer features a clock, indoor temperature, indoor humidity, and a wired temperature sensor for outdoor readings. Before using the device, ensure you remove the clear protective film from the LCD screen. The device requires one AA alkaline battery (not included) to operate.
Overview of features
The thermometer includes the following controls and display areas:

- Outdoor Temperature Display Area
- Indoor Temperature or Clock Display Area
- Indoor Humidity or Clock Display Area
- Backlight Button
- MAX/MIN Memory Buttons
- Indoor Temperature/Humidity or Time Display Mode Button
- °F/°C Select Switch and Clock Set Buttons: Located inside the battery compartment on the back of the unit.
Setup
To set up the thermometer:

- Slide the battery compartment cover open.
- Install one fresh AA alkaline battery. Ensure the positive (+) and negative (-) polarity markings match the markings inside the compartment.
- Use the switch inside the battery compartment to select between Celsius (°C) or Fahrenheit (°F).
- Replace the battery cover.
Placement
Indoor Monitor: Place the unit in an area free of water, dust, and direct heat, as these can affect the accuracy of the readings.

Outdoor Wired Sensor: The wired probe must be placed outside. You can route the wire through a window, ensuring the window frame does not pinch or cut the wire. The sensor can be mounted using the provided adhesive pad or the integrated screw/nail hole.
Operation
Display Modes: Press the Indoor Temperature/Clock Selection button to toggle between viewing the current time and the indoor temperature.

MAX/MIN Memory: Press the MAX/MIN button for temperature or humidity to view the recorded maximum and minimum values. The MAX and MIN indicators will appear on the display. To clear the currently selected MAX/MIN values, press the C button.
Specifications
- Wired Probe Temperature Range: -58°F to 140°F (-50°C to 70°C)
- Humidity Range: 20%-90% RH
- Battery: 1 x AA alkaline battery
Note: The thermometer will display LO or HI if temperature or humidity readings exceed the specified ranges.
Safety and Disposal
Follow the polarity diagram in the battery compartment. Do not mix old and new batteries or different types of batteries. Do not use rechargeable batteries. Dispose of old or defective batteries in an environmentally safe way and in accordance with local laws and regulations.
Manufacturer information
AcuRite
Practical help
Common problems
The temperature or humidity reading is out of the measurable range.
Replace the AA battery with a fresh one.
Before use
- Remove the clear protective film from the LCD screen.
- Install 1 fresh AA alkaline battery.
- Ensure battery polarity (+/-) matches the markings in the compartment.
- Select °C or °F using the switch inside the battery compartment.
Specs in practice
- Wired Probe Range
- -58°F to 140°F (-50°C to 70°C)
- Humidity Range
- 20%-90% RH
Images and diagrams
- The battery compartment contains the °F/°C select switch and clock set buttons.
- The wired probe can be mounted using the adhesive pad or the integrated screw/nail hole.
Manual page author
Emily Carter
User documentation editor
Prepares concise manual descriptions and highlights the most useful setup, operation, and maintenance information for readers.