Skip to main content

Honeywell 5821 Wireless Temperature Sensor & Flood Detector NEW FRESH STOCK - 5821 Sensor Only

$106.16

  • Free US shipping
  • Arrives

You will get the following based on the option you choose:
- 5821 Sensor Only:
   You will only get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector
- 5821 Sensor and FP280 Probe:
   You will get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector AND one Honeywell Home FP280
   Wireless External Flood Probe Sensor
- 5821 Sensor and T280R Probe:
   You will get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector AND one Honeywell Home T280R
   Remote Temperature Probe
GENERAL INFORMATION
The ADEMCO 5821 Flood Detector & Temperature Sensor is a wireless transmitter used with Honeywell’s alarm
systems that support 5800 series devices. The 5821 can be configured to operate,
  • as a stand-alone temperature sensor and/or,
  • as either a Flood Detector or Remote Temperature Sensor.
The 5821 in combination with the FP280 probe can be used to sense floods in basements
and other areas where there is a possibility of flooding. The 5821 will send an alarm when the preset
temperature limit is exceeded or when a flood is detected. Temperature monitoring and flood detection is
dependent on the operating mode selected.
The 5821 in combination with the ADEMCO T280R temperature probe is ideal for monitoring refrigerators and
freezers in restaurants, kitchens and warehouses where food storage is a concern.
A separate 5821 is required for each external probe being used.
  • Flood detection is monitored remotely using the FP280 probe with the supplied resistor.
  • Room temperature is monitored at the device using the 5821’s internal sensor.
  • Refrigerator or Freezer temperature is monitored remotely using the ADEMCO T280R temperature probe.
In refrigerator or freezer applications, when the temperature increases past the high threshold limit and a delay of
greater than 30 minutes passes, an alarm is triggered. This preset delay offers greater reliability against false alarms,
especially due to open refrigerator or freezer doors.
The following are manufacturer specifications:
Honeywell 5821 Wireless Temperature Sensor & Flood Detector 
Product Overview:
Ideally suited for applications including bathrooms, laundry rooms and basements, the 5821 helps protect against temperature fluctuations and flood conditions. The versatile device can be configured to operate as a standalone temperature sensor and/or a remote temperature sensor or flood detector. Fully compatible with Resideo Total Connect Remote Services, it can send users email or text message alerts when detecting floods or extreme temperatures so they can take action to minimize and avert damages.
Main Features:
Cold Temperature Detector 45°F
Warm Temperature Detector 75°F
Hot Temperature Detector 95°F
Up to 10 year battery life, which reduces user maintenance
Completely wireless, which greatly reduces installation time and maximizes placement options
Capable of monitoring cold (45°F) temperature and flood detection simultaneously
One 3V lithium battery included
Compatible with all 5800 Series wireless receivers
Honeywell Home FP280 Wireless External Flood Probe Sensor
Product Overview:
Wireless Temperature Sensors and Flood Detectors are Ideally suited for applications including bathrooms, laundry rooms and basements, the 5821 helps protect against temperature fluctuations and flood conditions.
The Resideo Honeywell FP280 Flood Probe Sensor intended for use with Honeywell 5821 and 470-12 wireless transmitter sensors. When the FP280 senses water it sends an alarm to the directly wired transmitter, which then sends the alarm initiating signal wirelessly to the Honeywell control panel.
Main Features:
Wire and Built-In Resistor included
Self-Adhesive and/or Screw Mount
Wall or Floor Mounted
Honeywell Home T280R Remote Temperature Probe
Product Overview:
The Honeywell T280R is a temperature probe intended for use with Honeywell 5821, T280 or TS300 sensors
Main Features:
Mounting Specifications
Temperature Detection
Water-Resistant

Isin:
IOK8UMIL2QY4

$106.16

  • Free US shipping
  • Arrives

In Stock

Sold by , Fulfilled by IBSPOT • Ships from US

IBSPOT Buyer Protection
  • Free 30-Day Returns
  • Full Refund for Damaged or Incorrect Items
  • Guaranteed Delivery or Money Back
  • Secure Checkout & Fast Support
scroll to top arrow
Honeywell 5821 Wireless Temperature Sensor & Flood Detector NEW FRESH STOCK - 5821 Sensor Only

Honeywell 5821 Wireless Temperature Sensor & Flood Detector NEW FRESH STOCK -...

$106.16

You will get the following based on the option you choose:
- 5821 Sensor Only:
   You will only get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector
- 5821 Sensor and FP280 Probe:
   You will get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector AND one Honeywell Home FP280
   Wireless External Flood Probe Sensor
- 5821 Sensor and T280R Probe:
   You will get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector AND one Honeywell Home T280R
   Remote Temperature Probe
GENERAL INFORMATION
The ADEMCO 5821 Flood Detector & Temperature Sensor is a wireless transmitter used with Honeywell’s alarm
systems that support 5800 series devices. The 5821 can be configured to operate,
  • as a stand-alone temperature sensor and/or,
  • as either a Flood Detector or Remote Temperature Sensor.
The 5821 in combination with the FP280 probe can be used to sense floods in basements
and other areas where there is a possibility of flooding. The 5821 will send an alarm when the preset
temperature limit is exceeded or when a flood is detected. Temperature monitoring and flood detection is
dependent on the operating mode selected.
The 5821 in combination with the ADEMCO T280R temperature probe is ideal for monitoring refrigerators and
freezers in restaurants, kitchens and warehouses where food storage is a concern.
A separate 5821 is required for each external probe being used.
  • Flood detection is monitored remotely using the FP280 probe with the supplied resistor.
  • Room temperature is monitored at the device using the 5821’s internal sensor.
  • Refrigerator or Freezer temperature is monitored remotely using the ADEMCO T280R temperature probe.
In refrigerator or freezer applications, when the temperature increases past the high threshold limit and a delay of
greater than 30 minutes passes, an alarm is triggered. This preset delay offers greater reliability against false alarms,
especially due to open refrigerator or freezer doors.
The following are manufacturer specifications:
Honeywell 5821 Wireless Temperature Sensor & Flood Detector 
Product Overview:
Ideally suited for applications including bathrooms, laundry rooms and basements, the 5821 helps protect against temperature fluctuations and flood conditions. The versatile device can be configured to operate as a standalone temperature sensor and/or a remote temperature sensor or flood detector. Fully compatible with Resideo Total Connect Remote Services, it can send users email or text message alerts when detecting floods or extreme temperatures so they can take action to minimize and avert damages.
Main Features:
Cold Temperature Detector 45°F
Warm Temperature Detector 75°F
Hot Temperature Detector 95°F
Up to 10 year battery life, which reduces user maintenance
Completely wireless, which greatly reduces installation time and maximizes placement options
Capable of monitoring cold (45°F) temperature and flood detection simultaneously
One 3V lithium battery included
Compatible with all 5800 Series wireless receivers
Honeywell Home FP280 Wireless External Flood Probe Sensor
Product Overview:
Wireless Temperature Sensors and Flood Detectors are Ideally suited for applications including bathrooms, laundry rooms and basements, the 5821 helps protect against temperature fluctuations and flood conditions.
The Resideo Honeywell FP280 Flood Probe Sensor intended for use with Honeywell 5821 and 470-12 wireless transmitter sensors. When the FP280 senses water it sends an alarm to the directly wired transmitter, which then sends the alarm initiating signal wirelessly to the Honeywell control panel.
Main Features:
Wire and Built-In Resistor included
Self-Adhesive and/or Screw Mount
Wall or Floor Mounted
Honeywell Home T280R Remote Temperature Probe
Product Overview:
The Honeywell T280R is a temperature probe intended for use with Honeywell 5821, T280 or TS300 sensors
Main Features:
Mounting Specifications
Temperature Detection
Water-Resistant

Isin:
IOK8UMIL2QY4

You will get the following based on the option you choose:

- 5821 Sensor Only:
   You will only get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector

- 5821 Sensor and FP280 Probe:
   You will get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector AND one Honeywell Home FP280
   Wireless External Flood Probe Sensor

- 5821 Sensor and T280R Probe:
   You will get one Honeywell Home 5821 Wireless Temperature Sensor and Flood Detector AND one Honeywell Home T280R
   Remote Temperature Probe


GENERAL INFORMATION
The ADEMCO 5821 Flood Detector & Temperature Sensor is a wireless transmitter used with Honeywell’s alarm
systems that support 5800 series devices. The 5821 can be configured to operate,
  • as a stand-alone temperature sensor and/or,
  • as either a Flood Detector or Remote Temperature Sensor.
The 5821 in combination with the FP280 probe can be used to sense floods in basements
and other areas where there is a possibility of flooding. The 5821 will send an alarm when the preset
temperature limit is exceeded or when a flood is detected. Temperature monitoring and flood detection is
dependent on the operating mode selected.

The 5821 in combination with the ADEMCO T280R temperature probe is ideal for monitoring refrigerators and
freezers in restaurants, kitchens and warehouses where food storage is a concern.

A separate 5821 is required for each external probe being used.
  • Flood detection is monitored remotely using the FP280 probe with the supplied resistor.
  • Room temperature is monitored at the device using the 5821’s internal sensor.
  • Refrigerator or Freezer temperature is monitored remotely using the ADEMCO T280R temperature probe.
In refrigerator or freezer applications, when the temperature increases past the high threshold limit and a delay of
greater than 30 minutes passes, an alarm is triggered. This preset delay offers greater reliability against false alarms,
especially due to open refrigerator or freezer doors.


The following are manufacturer specifications:

Honeywell 5821 Wireless Temperature Sensor & Flood Detector 
Product Overview:
Ideally suited for applications including bathrooms, laundry rooms and basements, the 5821 helps protect against temperature fluctuations and flood conditions. The versatile device can be configured to operate as a standalone temperature sensor and/or a remote temperature sensor or flood detector. Fully compatible with Resideo Total Connect Remote Services, it can send users email or text message alerts when detecting floods or extreme temperatures so they can take action to minimize and avert damages.
Main Features:
Cold Temperature Detector 45°F
Warm Temperature Detector 75°F
Hot Temperature Detector 95°F
Up to 10 year battery life, which reduces user maintenance
Completely wireless, which greatly reduces installation time and maximizes placement options
Capable of monitoring cold (45°F) temperature and flood detection simultaneously
One 3V lithium battery included
Compatible with all 5800 Series wireless receivers

Honeywell Home FP280 Wireless External Flood Probe Sensor
Product Overview:
Wireless Temperature Sensors and Flood Detectors are Ideally suited for applications including bathrooms, laundry rooms and basements, the 5821 helps protect against temperature fluctuations and flood conditions.
The Resideo Honeywell FP280 Flood Probe Sensor intended for use with Honeywell 5821 and 470-12 wireless transmitter sensors. When the FP280 senses water it sends an alarm to the directly wired transmitter, which then sends the alarm initiating signal wirelessly to the Honeywell control panel.
Main Features:
Wire and Built-In Resistor included
Self-Adhesive and/or Screw Mount
Wall or Floor Mounted

Honeywell Home T280R Remote Temperature Probe
Product Overview:
The Honeywell T280R is a temperature probe intended for use with Honeywell 5821, T280 or TS300 sensors
Main Features:
Mounting Specifications
Temperature Detection
Water-Resistant

  • Brand: Honeywell
  • Type: Temperature & Humidity Sensor
  • Model: 5821
  • MPN: 5821

Processing Time

  • We process and ship orders Monday through Friday, excluding holidays.
  • Most orders are processed within 1–3 business days, depending on product availability.
  • Processing time does not include delivery time, which varies based on your location and the product’s shipping origin.

Shipping Coverage

We currently ship to addresses within the United States only.

Products may ship from:

  • Our U.S. warehouses, or
  • Our international fulfillment centers (including Korea, Japan, China, Australia, Mexico, Canada, the United Kingdom, and the EU).

Each product page clearly displays the “Ships From” location before checkout.


Shipping Methods & Estimated Delivery

Shipping Method Estimated Delivery Cost
Free Shipping (US) 5–10 business days Free, available on eligible items
Standard Shipping (US to US by Item) 5–10 business days $5.95 for the first item, $3.00 each additional
Standard Shipping (From US Warehouse by Weight) 3–7 business days Starts at $5.95, increasing by $2 for every additional 4 oz (0.25 lb) up to 1 lb, then by $4 for each additional pound beyond 1 lb.
Extended Delivery (Ships from Overseas Warehouse) 10–20 business days $14.50 for the first item, $2.00 each additional

Shipping costs vary by product weight, quantity and origin. Exact rates and delivery estimates are displayed on each product page and confirmed during checkout.

Free Shipping

We offer free standard shipping on select products or during promotional periods. Availability of free shipping will be displayed on the product page and at checkout. 


Carriers

We primarily use USPS and UPS for U.S. deliveries. Items shipped from international warehouses may be handled by partner carriers depending on the country of origin.


Import Duties & Taxes

All import duties and taxes for goods imported into the United States are included in the product price. There are no hidden fees or additional charges at checkout.


Tracking & Notifications

Every order is fully trackable. You will receive a tracking number via email once your order ships. If your order ships in multiple packages, each package will have its own tracking number. If you don’t receive a shipping confirmation immediately, your order is still being processed and will arrive within the estimated timeframe shown at checkout.

You can track your shipment anytime using the Track Your Order page on our website.


Order Changes & Cancellations

If you need to modify or cancel an order, please contact our customer support team as soon as possible. Orders can only be canceled before they ship. Once shipped, cancellations are not possible, but you may request a return after the item is delivered.

Contact: support@ibspot.com


Item Not Received

If your tracking number shows “Delivered” but you haven’t received your package:

  1. Check with your local USPS or UPS office.
  2. Confirm that the shipping address provided was correct.
  3. If the issue remains unresolved, contact support@ibspot.com for assistance.

Damaged or Lost Parcels

If your package arrives damaged or fails to arrive, please contact us immediately. For deliveries to P.O. boxes, ibspot is not responsible for damage caused by weather, temperature, or theft.


Customer Support

For any questions about shipping, tracking, or delivery, our customer support team is here to help.

Email: support@ibspot.com

We’re always happy to help.

Please read our policy carefully before making a purchase.
We aim to ensure every customer has a smooth and transparent experience with ibspot.com.


Order Cancellation Policy

Customers may request to cancel an order before it has been shipped.
Once the package has been shipped, cancellations are no longer possible; however, you may still request a return after receiving your order.

How to Request a Cancellation

You can contact us through:

Please submit your cancellation request as soon as possible after placing the order to allow us to process it before shipment.


Return Policy

We accept returns for most items within 30 days of delivery for a full refund.

To be eligible for a return:

  • The item must be unused, in the same condition as received, and in its original packaging.
  • A tracking number must be provided to confirm the return shipment.

Non-Returnable Items

Certain products cannot be returned, including:

  • Perishable goods (for example, food, flowers, newspapers, magazines)
  • Intimate or sanitary goods
  • Hazardous materials or flammable liquids/gases
  • Gift cards
  • Downloadable software
  • Some health and personal care items

Partial Refunds (If Applicable)

Partial refunds may be granted in specific situations, such as:

  • Books with obvious signs of use
  • Opened CDs, DVDs, software, or vinyl records
  • Items not in their original condition, damaged, or missing parts not due to our error
  • Items returned more than 30 days after delivery

How to Return an Item

To initiate a return, please contact us at support@ibspot.com with your order number and details about the product you wish to return.
Our team will provide you with return instructions and a prepaid return label.


Shipping Cost for Returns

Please contact us before returning any item.
We will provide a free return shipping label.

If a return is sent back without prior contact or without our provided label, we cannot be held responsible for return shipping costs.

For items valued over $75, we recommend using a trackable shipping service or purchasing shipping insurance.
We cannot guarantee that we will receive your returned item if shipped independently.


Refund Processing

Once your return is received and inspected:

  • In-store returns are refunded to the original form of payment or issued as a gift card.
  • Mail-in returns using our prepaid label are refunded to the original payment method within 3–5 business days after we receive your return.

Please allow:

  • 5–7 business days for the return to reach our Returns Center.
  • An additional 3–10 business days for your bank to post the refund to your account.

Damages, Issues & Claims

Please inspect your order immediately upon receipt.
If you receive a defective, damaged, or incorrect item, contact us right away at support@ibspot.com.
We’ll evaluate the issue promptly and make it right.

Product Claims

Before purchasing, please review product details carefully.
If there is a problem with your order upon arrival, visit our Support Center or contact us directly to arrange return shipping or replacement.


Exchanges

We do not process direct exchanges.
The fastest way to get what you need is to return the original item and place a new order once your return is accepted.


Return Address

IBSPOT Return Center
15 Sawmill Ln
Dover Plains, NY 12522
United States


Customer Support

Our support team is available 24/7 to assist with cancellations, returns, or general inquiries.

Email: support@ibspot.com
Contact Form: Contact Us page

Oops!

Sorry, it looks like some products are not available in selected quantity.

OK

Subscribe To Our Newsletter

Disclaimer: Statements made, or products sold through this website, have not been evaluated by the United States Food and Drug Administration. Products are not intended to diagnose, treat, cure or prevent any disease.