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Honeywell S437A1009/U Sail Switch Airflow Proving SPST 3-1/2″ 120V

SKU: S437A1009/U

$391.88

Only 2 left in stock

Same-item volume pricing
QuantityUnit priceSaving
1–4$391.880%
5–9$372.295%
10+$352.6910%

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Honeywell S437A1009/U Sail Switch – Airflow Proving – SPST – 3-1/2″ Insertion

The Honeywell S437A1009/U Sail Switch is an airflow-activated proving switch designed to energize a burner circuit or control circuit when sufficient air velocity is present in the airstream.

Air velocity acting on the flat metal sail triggers the switch once airflow reaches the operating threshold. This unit is used primarily for draft inducing equipment and HVAC airflow verification applications.

Key Specs:

  • Model: S437A

  • MFG#: S437A1009/U

  • Switch Type: SPST (makes on velocity increase)

  • Insertion Length: 3-1/2 in.

  • Adjustable Differential: 550–900 FPM

  • Electrical Rating:

    • 8A @ 120V

    • 5A @ 240V

  • Use Case: Airflow proving, draft inducer activation, burner enable control

✅ Ideal for HVAC contractors, service techs, and industrial maintenance teams needing a reliable airflow proving switch.

Product details

Part / SKU S437A1009/U

Package includes

  • Honeywell S437A1009/U Sail Switch Airflow Proving SPST 3-1/2" 120V

Included components and any stated pack quantity are as described in this listing. Optional accessories shown separately are sold separately unless expressly included above.

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