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# of Relays
1 Relay
24V AC
Ease of Installation
Intermediate (Installs < 60 minutes)
Aube Technologies
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Relay is Compatible with 24V Thermostats for Improved Temperature Control and Comfort
Aube RC840 On/Off Switching Electric Heating Relay
Aube RC840 On/Off Switching Electric Heating Relay
Aube RC840 On/Off Switching Electric Heating Relay
Item# 300612
Price: Normally $47.28 
Hot Deal $35.26
Free shipping on orders over $175 - See Details


  • Compatible with 24V thermostats
  • Direct replacement for any brand name relay
  • Immediate relay activation provides improved temperature control and comfort
  • Epoxy-soundproofed relay ensures quiet operation
  • Low current consumption means multiple relays can be controlled by a single thermostat
  • Terminal board connection enables easy installation

Essential Info

The RC840 Electric Heating Relay is designed to control a line voltage resistive load from a 24V control signal. It is compatible with 24V thermostats, and 24V thermostats with 2-wire connections (R, W) or 3-wire connections (R, W, C). The RC840 operates silently and can be installed in bedrooms, living rooms, or any other occupied area without disturbing occupants. The Electric Heating Relay can be installed on the side of an electrical box, a distribution panel, or inside the wiring compartment of an electric baseboard (see Owner's Manual for wiring diagrams). On a call for heat, the relay is immediately activated; there is no delay. This increases temperature control and comfort of the room.


What's Included

  • 1x - On/Off Switching Electric Heating Relay
  • Specifications

  • Manufacturer: Honeywell
  • Manufacturer Part #: RC840
  • UPC: 775264094613

    24 VAC / 40 mA
    24 VDC / 35 mA
    0 to 95 % non-condensing
    12 AWG
    DIMENSIONS (H x W x D)
    68 x 85 x 36 mm
    2.7 x 3.3 x 1.4 inches

  • Reviews

    4 Ratings
    5 star: 100%  (4)
    4 star: 0%  (0)
    3 star: 0%  (0)
    2 star: 0%  (0)
    1 star: 0%  (0)
    Average Customer Rating
    (4 customer ratings)
    Share your thoughts with other customers
    MERRITT B -- dallas, TX   4/28/2013
    Good supplier, great service and tech support
    RICHARD -- silver spring, MD   11/18/2011
    The relay is doing the job properly. It does require a separate 24 volt transformer. I tried to get Aube's RC840-120 from you, but your phone agent refused to order it for me. So I went elsewhere and ordered a few. It saves on installation time and makes a neater job. Listen to your customers needs if you want to sell more items!

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