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Carrier HR81LG020 Flow Switch

Rating:
5 5 1
1  Review Add Your Review
Special Price $711.39 Regular Price $789.65
In stock
SKU
HR81LG020
The Carrier HR81LG020 Flow Switch functions as a water flow monitoring part which specifically operates in HVAC systems throughout boilers and hydronic heating systems. The device checks flow changes to activate or deactivate equipment according to established conditions thus maintaining system functionality. The flow switch protects systems from insufficient water flow while improving reliability and energy efficiency and preventing expensive maintenance costs which makes it essential for heating and cooling system performance.
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HVAC Controls & Electrical, Switches, Control Switches
Manufacturer:
https://www.partshnc.com/media/catalog/product/h/r/hr81lg020.jpg
Manufacturer Name: Carrier
Product Number: HR81LG020
OEM Part Number: HR81LG020
Product Description: Flow Switch
Weight:0.27lbs/122.47g

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Product Questions (2)
Customer Questions
What maintenance is required for the Carrier HR81LG020 Flow Switch?

Regularly inspect the flow switch for debris, corrosion, or loose connections that may affect operation. Clean the sensor area and ensure the switch moves freely. Proper maintenance ensures accurate system monitoring, and always disconnect power before performing any checks.

What are common issues with the Carrier HR81LG020 Flow Switch?

  • Inconsistent or inaccurate flow detection.
  • Switch failing to activate or respond.
  • Debris obstructing the switch mechanism.
  • Loose or improperly connected wiring.

Installation Steps

Step 1: Turn off the HVAC system power before starting.

Step 2: Locate the existing flow switch and disconnect wiring carefully.

Step 3: Remove the old switch from the pipe or mounting bracket.

Step 4: Install the new flow switch, ensuring correct orientation and secure attachment.

Step 5: Reconnect the electrical connections exactly as they were on the old switch.

Step 6: Restore power and test the system to confirm proper flow detection and safe operation.