Blue Sea Systems High Temp Temperature Sensor, IP65, -40°F to 300°F, 18 in Wire

Overview

The Blue Sea Systems 1821 is a high-temperature sensor for monitoring raw water exhaust temperature on a boat without drilling into the pipe. It mounts on the outside of the surface being monitored and works with Blue Sea Systems products that accept a temperature sensor, including the P12 Charger, M2 OLED, and Mini OLED meters.

Its sensing range runs from -40°F to 300°F (-40°C to 150°C), which makes it useful anywhere a standard low-temperature probe would not be enough. The sensor has an 18-inch lead for short routing runs near the monitored point, and its IP65 construction is suited to wet onboard spaces that see spray and washdown water, but not full submersion.

Key features

• Measures from -40°F to 300°F (-40°C to 150°C) for higher-heat monitoring points such as raw water exhaust
• External surface-mount setup lets you monitor exhaust temperature without drilling into the hose or pipe
• Compatible with Blue Sea Systems products that require a temperature sensor, including P12 Charger, M2 OLED, and Mini OLED meters
• IP65-rated body handles water spray and washdown conditions, but it is not a submersible sensor
• 18-inch lead helps with short, tidy cable runs in engine spaces and nearby monitoring locations
• Non-polarized leads connect in either order, which keeps wiring straightforward during installation
• Multiple mounting options, including included double-sided tape, a through-hole for a #8 screw, or a hose clamp on the outside of a pipe

Installation and setup

This sensor is meant to read temperature from the outside of the component you are watching, not from inside the fluid path. On a raw water exhaust run, it can be strapped to the outside of the pipe or hose so you can track temperature changes without opening the system.

For a fixed mount, the through-hole accepts a #8 screw. For pipe mounting, a hose clamp can be used to hold the sensor against the outside surface. The included double-sided tape is useful on a clean, dry mounting point when a clamp or screw is not the better fit.

Compatibility and fit

This is a good match for boats that already use a Blue Sea Systems charger or display with a temperature-sensor input and need a remote sensor at the engine space or another hot surface. Before ordering, check that the 18-inch lead will comfortably reach the connection point on your charger or meter, especially if the display is mounted away from the area being monitored.

Because it is a high-temperature, non-submersible sensor, it fits dry-contact surface sensing better than applications where the probe needs to sit underwater or inside a tank. That makes it especially practical for engine-room monitoring where spray, heat, and vibration are part of normal use.

What’s included

• Temperature sensor
• Double-sided tape

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Orders of $100 or more qualify for free shipping when eligible. For orders under $100, shipping costs are calculated at checkout based on destination, package weight, and selected service. International shipping is available for eligible products, and certain items may require additional handling, warehouse transfers, or may ship directly from the manufacturer, which can affect processing time.

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We ship throughout the United States and to most international destinations for products eligible for international shipping. International orders may be subject to customs duties, taxes, brokerage charges, or other import fees, which are the customer's responsibility and are not included in the product or shipping price. PO Boxes are accepted only when shipping through USPS, and not all packages qualify for this option. If your order does not arrive within the estimated delivery window, please contact us at info@apollolighting.com or +1 (954) 375-0100 so we can assist with locating your package.

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Returns may be requested within 30 days of receiving your order. Items must be unused, uninstalled, unaltered, and returned in their original packaging with all tags, packing materials, blank warranty cards, manuals, instructions, accessories, and included items. Certain products, including installed or used electronics, electrical components, lighting, consumables, custom or special-order items, cut-to-length products, safety equipment, and merchandise exposed to water or marine conditions, may not be eligible for return.

To request a return, sign in to your account and select the applicable order and items, and submit your request for review. Eligible unfulfilled items may also be submitted for cancellation within 1 hour of placing the order. Returns or cancellations are not considered approved until you receive confirmation from Apollo Lighting. Please do not ship or drop off merchandise before receiving return approval and instructions.

Customers are responsible for arranging and paying for return shipping unless the return is due to an error by Apollo Lighting or the item is verified as defective, damaged, or incorrect. Missing, damaged, defective, or incorrect items must be reported within 2 business days of delivery, and photos or other documentation may be required for review. If the issue is verified, Apollo Lighting may provide or reimburse return shipping and issue a replacement or refund depending on the circumstances. International customers are responsible for return shipping, duties, taxes, customs charges, brokerage fees, and other costs associated with an international return.

After your return is received and inspected, approved refunds are issued to the original payment method and may take 5-7 business days to appear after processing. Original shipping and handling charges are nonrefundable, and the value of any included free items that are not returned may be deducted from the refund. Apollo Lighting does not charge a standard restocking fee on eligible returns. Returns that are incomplete, damaged, installed, used, altered, improperly packaged, or otherwise do not meet the eligibility requirements may be refused. We recommend using a trackable and appropriately insured shipping service for all customer-arranged returns.

For assistance, contact info@apollolighting.com or call +1 (954) 375-0100.

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Many products sold by Apollo Lighting include a manufacturer's warranty covering defects in materials or workmanship. Warranty terms vary by brand, product category, and model, so eligibility, coverage duration, exclusions, and available remedies are determined by the applicable manufacturer. We recommend reviewing the warranty information provided with your product before installation or use, especially for marine electronics, navigation equipment, lighting, electrical systems, pumps, safety equipment, and other specialized marine products.

If you need warranty service, the claim must follow the process established by the manufacturer, authorized service center, or designated warranty provider. You may be asked for proof of purchase, a serial number, product registration, photos, maintenance or installation records, or other documentation. Apollo Lighting does not determine or modify a manufacturer's warranty coverage or final claim decision, but we are happy to help provide purchase information and direct you to the appropriate manufacturer or warranty resource.

Keep your receipt, product documentation, serial number information, and original packaging when practical. Damage caused by normal wear, misuse, improper installation, insufficient maintenance, corrosion, impact, unauthorized modifications, electrical issues, or operation outside the manufacturer's specifications may not be covered. Warranty claims are separate from standard returns, so a product that has been installed, used, or exposed to marine conditions may no longer qualify for return while still remaining eligible for evaluation under the manufacturer's applicable warranty.

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