Skip to content

TEMP-1B alert outside a temperature range

Difficulty: Level 1

Your Apollo TEMP-1B sends its temperature probe reading to Homey whenever it's awake, and every new reading can start a flow. In this guide you build two flows in the Homey mobile app that keep watch on a freezer: the first sends a push notification when the probe gets too warm, the second when it gets too cold.

Before you start

  • Add your TEMP-1B to Homey with the Apollo Automation app. See Getting started.
  • Plug the temperature probe into the TEMP-1B. Open your TEMP-1B's Settings and, under Probes and offsets for TEMP-1 and TEMP-1B, set Select probe to Temperature. With Food selected, the temperature probe sends no readings.
  • Install the Homey mobile app on every phone that should get the alert.
  • Decide how quickly you need to hear about a problem. A sleeping TEMP-1B only reports when it wakes; How often your TEMP-1B reports explains the trade-off with battery life.

How often your TEMP-1B reports

Your flows can only react to readings the TEMP-1B sends, and it only sends them while it's awake.

  • With Prevent sleep on, the TEMP-1B stays connected and reports the probe about once a minute. This drains the battery fastest.
  • With Prevent sleep off, it sleeps between readings and reports once each time it wakes, every 12 hours unless you change Sleep duration. An alert can arrive that long after the problem started.

For a freezer, set Sleep duration (in hours) to the longest delay you're comfortable with, for example 1 for a reading every hour. Shorter sleeps use more battery. Both settings are under Battery settings (if battery is present) in your TEMP-1B's Settings, and Prevent sleep walks you through changing them.

Change settings while the TEMP-1B is awake

Homey can only change the TEMP-1B's settings while it's awake. If Homey shows The device is asleep. Settings can be changed when it next wakes up., wake the sensor and try again. See How to wake up your sensor.

Pick your range

Find out what your freezer normally swings between before you set any limits. That way the alert only fires when something is actually wrong.

  1. Place the probe in the freezer and run its flat cable out through the door seal. Keep the TEMP-1B itself outside the freezer, somewhere cool and dry: only the probe and its cable can handle the cold.
  2. Leave it for a few hours so the reading settles. Most freezers should sit at or below -18 °C (0 °F).
  3. In Homey Insights, look at your TEMP-1B's Temperature Probe history. Note the highest and lowest readings.
  4. Pick a maximum a little above the highest reading and a minimum a little below the lowest. This guide uses -10 °C and -30 °C; yours will likely differ.

You now have a range that covers normal use and flags a real problem.

Enter your limits in degrees Celsius

The Temperature Probe reading, and the Temperature token the flows below compare, are always in °C. If you think in Fahrenheit, convert first: -10 °C is 14 °F, and -30 °C is -22 °F.

Flow 1: Too warm

This flow runs each time the probe reading changes, checks it against your maximum, and sends the alert when the freezer is too warm.

  1. In the Homey mobile app, tap Flow in the bottom bar, then tap + at the top right (or Create a Flow if you have none yet).
  2. Under When..., tap Add Card. Open Apollo Automation under Apps, and choose your TEMP-1B.
  3. Choose the card Temperature probe changed. It hands the new reading to the rest of the flow as the Temperature token.
  4. Under And..., tap Add Card and add Homey's built-in condition for comparing numbers. Set it to check that the Temperature token is greater than -10.
  5. Under Then..., tap Add Card and choose Send Message to User from Push Notifications.
  6. Type a message, for example Check the freezer! The TEMP-1B probe reads, and add the Temperature token after it.
  7. Tap User and pick who gets the alert, such as Everyone, then tap the check mark at the top right.
  8. Tap Next. Name the flow, for example Freezer too warm, and tap Save Flow.

The flow now shows in My Flows. The next probe reading above -10 °C sends the alert to your phone.

Flow 2: Too cold

The second flow mirrors the first. Build it the same way, with these changes:

  1. In the And... condition, check that the Temperature token is less than -30.
  2. Change the message, for example to The freezer is colder than usual. The TEMP-1B probe reads, followed by the Temperature token.
  3. Name the flow Freezer too cold and tap Save Flow.

Both ends of your range are now covered: you hear about it whether the freezer warms up or runs too cold.

Expect a reminder with each new reading

Temperature probe changed runs every time the reading changes, not only when it crosses your limit. While the probe stays out of range, every change sends another notification (up to once a minute while the TEMP-1B is awake, or once per wake-up while it sleeps) until the temperature is back inside your range. To pause the reminders while you deal with the freezer, switch the flow off in My Flows, and switch it back on afterwards.

Test your flows

To check the alert without warming up your freezer, tap the play button next to a flow in My Flows. It runs its Then cards once, and a green check mark confirms it ran. Your phone gets the notification.

If a flow doesn't run when the freezer is out of range:

  • Check that Select probe is set to Temperature and that the Temperature Probe reading updates each time the TEMP-1B wakes.
  • Check that your limits are in °C.
  • Check that both flows are switched on in My Flows.

Optional: sound the TEMP-1B's buzzer too

The TEMP-1B can also raise the alarm on its own. When you turn this on, the sensor checks every probe reading against a minimum and maximum you store on the device and sounds a short siren from its buzzer when the reading is outside them. It works alongside your flows, so anyone near the freezer hears it even if their phone is on silent. Like your flows, it only checks readings the TEMP-1B takes while it's awake.

  1. Open your TEMP-1B's Settings.
  2. Under Probes and offsets for TEMP-1 and TEMP-1B, set Minimum probe temperature and Maximum probe temperature in °C, for example -30 and -10.
  3. Under Temperature range and alarm settings for TEMP PRO-1, turn on Alarm when temperature outside configured range. The group is named for the TEMP PRO-1, but this setting also switches the TEMP-1B's alarm on and off.

The TEMP-1B now sounds the siren with each probe reading outside your range, until the reading is back inside it.

Use the probe settings, not the TEMP PRO-1 ones

Minimum temperature and Maximum temperature in the TEMP PRO-1 group belong to the TEMP PRO-1 and don't change anything on a TEMP-1B. Set the range with Minimum probe temperature and Maximum probe temperature instead.

Next step: know when dinner is ready

Your freezer is covered. The automation examples put the food probe to work: a flow that lights your TEMP-1B green and sends you one notification when your food reaches its target temperature.

Build the food probe flow