Marcell MAR501 Cellular Power, Temperature, Freeze Alarm with Wireless Water Sensor
Freeze Alarm

Marcell MAR501 Cellular Power, Temperature, Freeze Alarm with Wireless Water Sensor

  • Description

    Marcell MAR501 Cellular Freeze Alarm System

    Cell Phone Freeze Alarm

    Cellular communication - No phone line or Internet required!

    The MarCell MAR-501 is a cellular freeze alarm, perfect for applications without a land line. The Marcell is perfect for monitoring your vacation home, winter home or remote property while unoccupied. The alarm will monitor for temperature and humidity problems, water leaks and power outages.  When power temperature or humidity rises or falls outside your normal range, or power fails, or a flood is detected, you'll receive an email or text message to let you know so you can check it out right away.

    Additional water & flood sensors (Water Spuck) can be purchased here:

    The Freeze Alarm Marcell communicates via the cellular network to the Sensored Life cloud service, where users can easily program the alarm points, the alarm contacts and log in at any time to monitor the temperature and humidity levels.  An on board battery keeps it working during power failures.  The cellular communicator is built in and the cloud subscription service (required) starts as low as $8.25 per month.

    Please note:  MAR500 has been discontinued and replaced by MAR501 which is the same product and now includes a wireless water sensor.

    In Canada?  See it here:


    • No Phone Line or Internet required at monitored location!
    • Monitor for hi and low temperature and freezing
    • Monitor for power failures
    • Monitor for water leaks and floods
    • Monitor for hi and low humidity
    • Will send alerts via text, email, and telephone calls.



    How often does Marcell report in with temperature and humidity data?
    HomeSitter checks current temperature and humidity against your settings every 10 seconds. If the current readings are outside of your “safe range”, an alert will be sent immediately. If readings are within your safe range, they are recorded every hour locally and uploaded every 6 to 8 hours to the cloud service for historical logging.  At that point, this data is displayed on the web site in graph or chart form.

    In case of an alarm condition, the alert is sent right away!

    A subscription is required to monitor the property and receive alarm notifications. Service subscriptions are available on a month-to-month, seasonal or annual basis via starting at USD$8.25/mo.

    How does the cellular billing work?
    Part of the beauty of the MAR-500A and MAR501 ; is that you can turn the cellular connection on and off on a monthly basis so you are only paying for the coverage you need when you need it. You can do this online at any time - quickly, easily and with no hassle.  Billing plans are available starting at USD$8.25 per month.  Note that Marcell uses the Verizon network and requires a decent cellular signal at the installation location.  Works in continental USA only.

    Also known as part# HS-500SL

    MarCell Cellular Freeze Alarm Details

    • Power: 110VAC to 5VDC, 2A plug-in power adapter with built-in battery backup
    • Temperature Alarm Range: 20 to 120F (-7 to 49C)
    • Humidity Alarm Range: 10 to 90% RH
    • Operating Temperature Limits: 20 to 158F (-7 to 70C)
    • Rechargeable Battery: Internal 3.7V 800mAh Li-ion rechargeable


  • Reviews


    Thank you!

    Love this product! I am a property manager in Minnesota, so winters can be quite a drain on our resources when we have vacant properties - driving to/from them daily/weekly/monthly to check thermostats to ensure pipes don't freeze - this product allows us to spare those trips by the click of a mouse and touch of a keypad. Thank you!
  • Details


    Current Stock:
    SKU: MAR501
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