Weil McLain 381-356-586 Outdoor Sensor

The Weil McLain 381-356-586 12K Ohm Outdoor Air Sensor is a wired 12K ohm outdoor air temperature sensor for Weil McLain boilers. Weil McLain's CGa Series 4 and CGi Series 5 parts lists carry it as the Outdoor Temperature Sensor - Wired in their optional kits sections, so it is a manufacturer-listed accessory for those boiler lines. The sensor ships with wire leads, and the photo shows it with the mounting screws and anchors.

An outdoor air sensor reports the outside temperature to the boiler control. On a control that supports outdoor reset, that reading lets the boiler lower its supply temperature when it is mild outside and raise it when it is cold, which cuts short cycling and fuel use. A sensor that has failed, corroded or been damaged by weather can leave the control reading a false outdoor temperature, so the boiler may run hotter or cooler than it should.

Mount the sensor on the outside of the building in a shaded spot, away from direct sun, vents, exhaust and other heat sources, and keep the wire run neat and protected. The 12K ohm rating is part of the part description, and it is worth confirming that your control expects the same sensor before you order. If you are not sure whether your boiler uses this sensor, send us the boiler model and serial number and our team will help confirm.

Key Benefits

• Listed in Weil McLain Parts Lists: 381-356-586 appears as the wired outdoor temperature sensor in the CGa Series 4 and CGi Series 5 optional kits sections.
• 12K Ohm Sensor: The resistance rating is part of the manufacturer's description, so it can be matched against what your control expects.
• Wired Leads and Mounting Hardware: Supplied with wire leads, and the photo shows screws and anchors for mounting it on the outside of the building.
• Supports Outdoor Reset: On a control that offers outdoor reset, the sensor lets the boiler adjust supply temperature to match the weather.

Common Questions

• What is the 381-356-586? It is a wired 12K ohm outdoor air sensor, listed by Weil McLain as the Outdoor Temperature Sensor - Wired in the CGa Series 4 and CGi Series 5 parts lists.
• Where should the outdoor sensor be mounted? On the outside of the building in a shaded location, away from direct sun, vents and other heat sources, so it reads true outdoor temperature.
• Will it work with my control? The 12K ohm rating is what to check. Send us the boiler model and serial number and our team will help confirm before you buy.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.