New owner of AcuRite Model 75075. Outdoor temp (just now installed) is reading 7 degrees higher than actual tempperature. How lond does it take for the indoor & outdoor unit to get in Synch?

Question edited for a LOT more clarity. full 'make model (what it is)'.
Question moved from Computers to Model category.

Remove the batteries from both indoor and outdoor unit. Leave them out for 10 minutes. Replace the outdoor sensor with a new battery (2xAA), and then new batteries in the main unit (3xAA).

00605 Wireless Weather Station + Companion Instructions

AcuRite https://www.acurite.com > media > manuals > 0... PDF NOTE: When replacing the batteries for the wireless sensor, remove the batteries from the sensor and clear that sensor's channel on the main unit by pressing ...
6 pages

Hard Reset for Sensor Models 00606TX/06009RMA1 & ...

AcuRite https://support.acurite.com > en-us > articles > 360007...
The following reset steps can be performed to correct issues of the sensor not connecting to the display. Symptoms of the sensor not...
https://fccid.io/RNE00605TX/User-Manual/User-Manual-707183

..

The indoor temperature and humidity and outdoor temperature readings can be calibrated on the display to improve accuracy. Calibration can improve accuracy when sensor placement or environmental factors impact your data accuracy. 1. To access calibration mode, press AND HOLD the "?", "?", and "SET" buttons for at least 5 seconds. 2. Once in calibration mode, the preference you are currently setting will be highlighted on the display. 3. Press the "?" or "?" buttons to calibrate the data value higher or lower from the actual reading. 4. Press the "SET" button to confirm the calibration adjustment. The " " icon will remain illuminated next to calibrated values. 5. The next adjustable data will begin flashing, indicating it is ready to be calibrated. Repeat Steps 1 - 4 to calibrate additional data. The preference set order is as follows: OUTDOOR TEMPERATURE INDOOR TEMPERATURE INDOOR HUMIDITY BAROMETRIC PRESSURE (must be set to MANUAL mode; see page 12) After 20 seconds of inactivity, the display will save the adjustments and exit calibration mode. Note: Calibrations will be erased if the display is reset or if batteries are removed and the power adapter is unplugged.

Here's the manual for the AcuRite Weather Forecaster. If it's not showing the outside temperature, make sure the A-B-C switch is set to match the display unit. Not doing so might be the reason it's not synchronizing and displaying the outdoor temperature. https://www.acurite.com/media/manuals/75077-75107-instructions.pdf

We would recommend a reset of your unit. Please verify that you are using good-quality, standard alkaline batteries such as Energizer or Rayovac, then follow the steps below.
1. Bring both the sensor and display unit indoors and remove at least one battery from each.
2. Make sure the A-B-C switch on both units match. Sometimes changing to a different channel can help.
3. Reinstall the battery in the outdoor sensor.
4. Reinstall the battery in the display unit.
5. Let the units sit within a couple feet of each other for about 20 minutes to gain a strong connection.
If you need any further assistance, please contact AcuRite Customer Support at 1-877-221-1252 or [email protected].

how do i set my clock for accurite 00604RX

HH means it is showing the high temperature you (most likely accidentally) set with the MAX MIN / + button, which is easy to do when setting the clock. Just press that button again until the reading appears.

Sometimes the RF frequency from the outside transmitter loses contact with the clock's frequency ( it has happened to me only twice in 6 years ), and then the outside temp will not show. Simple solution to fix this is: Take down the outside transmitter and the internally mounted clock. Remove batteries from both. Wait about 10 mts. First install batteries in the transmitter, then after about 30 seconds, install batteries in the clock. In about 5 mts, you will find the clock showing the external temp like before.

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